If you want to go DEEP down the dynamo rabbit hole, jump on my website. You'll find a crazy amount of info on dynamo hubs, lights, USB chargers, wiring, batteries and more: www.cyclingabout.com/category/equipment/bike-equipment/dynamo/
@@Cyclingabout I run a Rohloff on both of my bikes. I love the sensation of direct drive with this hub. And I got them cheap from German 2nd hand market. On one bike I have a SON dynamo and the cheapest Shimano dynamo on the other. Cant complain on either one of them, except that the SON has bare metal connectors which oxidized and I had to replace the lower part of the wiring (so a win for the Shimano here).
@@Cyclingabout yeah, I accidentally squeezed the wire ends when taking out the front wheel, only to find out the light system is not working any more when I reinstalled the wheel. I unwrapped the wires (cut the housing) and the wires were green on the inside. I had some pieces of copper wire laying arround and just replaced this part of wire without soldering and put some heat shrink tubing over it. It works like a charm now. But this would be hard to fix on an expedition without the wire.
Pure passion, yep, but man (or even cyclist) does not live by passion alone! A bit of donor money helps fuel the passion. His reviews are the embodiment of scientific method. In equipment alone they must cost a bit.
Very interesting comparison. Previous to this, the two data points I was going off of (and why I have a dynohub) were: 1: my SON dynohub, when off, has less resistance than all but the very best racing hubs. We measured this by: flip the bikes over, give the wheels an equal-force spin, and then see how long until the wheel stops spinning, the bearings and construction are so much better in the SON hub than in most non-dynamo front hubs that it will spin longer, despite the added magnetic resistance. It just goes and goes and goes. And that certainly matches my on-bike perceptions: when the hub is off, I don’t feel a thing, and I can coast a long time if I’m in a good tuck. 2: I definitely notice the dynohub kick in. I have automatic lights, so it sometimes turns on in the middle of a ride, like when I go under a bridge. That said, the resistance with the lights on is still /way/ less then the semi-knobby tires I use in winter, and the difference between dynohub on and dynohub off is also much less noticeable than the difference between tires at 60 psi and same tires at 80 psi. Mostly, I notice the subtle vibrational hum coming up through the handlebars, not any additional resistance.
Very nice video. One minor point. At the end of the video you say the Cyo headlight, introduced about 12 or 13 years ago is half the brightness of the IQ-X, which is true. However the Cyo Premium, which was introduced 7 or 8 years ago is 80 lux, vs 100 lux for the IQ-X. So anyone buying a current Cyo headlight is most likely buying a Cyo Premium, which is almost as bright as the IQ-X. The difference is enough to be noticeable if you're riding side by side and have the lights aimed exactly the same, vertically. But even a small difference in aiming the light will have a more significant difference in the beam's brightness on the road. That being said, if you're riding in traffic at night in the rain, you never have enough light! Peter J White Peter White Cycles LLC
@@Boss_Tanaka Completely neglectable if you don't have your lights turned off. More importantly: When you are actually riding in the dark, the old side friction Dynamo REALLY slows you down. If you regularry ride in the dark, they are to crappy to use.
@@sagichdirdochnicht4653 And from my childhood memories it'll also let you down at times when the tyres get wet, but I must admit that they were maybe not always perfectly aligned or in the best state of maintenance. That poor efficiency and then also powering an incandescent bulb is something I really don't miss these days.
With a little tiny bit of drag you get to see more on the rides 😉 I love my SON with the Edelux and the B&M E-Werk on my Fatbike. And I have to wait for my buddy all the time anyway, so that drag does not bother me at all!
Idk how I have missed this channel. Great video and certainly gives me food for thought. I am just thinking of using it to charge my battery banks. Seems more dependable than using my solar wing and hoping for good weather. Thanks for the well researched info. Ride safe!
Thanks for more great content, Alee! I've always been curious about just how much of a difference dynamos make. It's surprising how many ultra racers use them given that overnight time penalty you mentioned! Guess that's another reason to sleep at night 🤣
In my city, we have a bike share system and all of the bikes there use Hub Dynamos to power the integrated lights, I don't really have an issue using them and having the lights is a great safety feature
Really interesting, I'm just getting the parts together to rebuild an old bike from my shed to use as a commuter and now think that a dynamo hub and lights will be the ideal answer for me.
Dynamo on a bike make much more sense nowadays with high efficiency LEDs. I recall when using a two 6 V 10 W Sylvania halogen bulbs setup (the bulbs with 30 hours lifetime). While with the LED the dynamo uses 1.5% of the total pedal power, with the halogen illuminator I went up to 10% of pedal power (for the same luminous flux). For time critical runs, we added a 6 V 10 Ah lead-acid battery, which provided 2 hours of light at 20 Watts, or 4 hours at 10 Watts. Thanks for the video...
Love my son and my klite. First real test was the Pioneer 400 in September and it worked flawlessly and I easily charged stuff as I rode. Keep needing-out!
Thanks for sharing this data. If I were riding something like the TCR, I’d be tempted to switch off the dynamo when climbing, and just use some small battery lights, and then switch the dynamo back on at the top of the hill. Interesting.
Another great review, it’s interesting to see the data... I currently use a Son28, K-Lite set up, so far, supper happy with it. Look forward to further videos from you.
Hey, great video, much needed info. Based on this video, the findings here I went with the Son 28. The only issue for me will be on Audax rides. I ride a Thorn Mercury which I also use for tours. For shorter Audax I had another wheel build with a normal hub. It was more for weight reasons. It's far easier for my legs to use USB lights, I take another set that are charged. Many riders still run the sun 28 on audax.
Nice video. Your recent article on rim dynamos was interesting too. It would be interesting to see a rim version of this video with comparison to hub. Pedalec should be more efficient. With caveat around mud.
I can tell you from experience going back a while, you can feel a rim dynamo very distinctly. Back in the olden days of crap batteries and bulbs the generator was reliable and ready when you needed it. When you flipped the generator off your bike felt like a rocket.
I've always wondered about the effects of electrical loading on dynamo drag. The ones I've tried have been the flip on your tires type and they make noticeable drag.
Great video, thanks a lot! I do think though that you overestimate the w/kg output of the average bikepacker. This number will vary massively across cyclists of course, but I do think that 2 w/kg average for bikepacking is quite a big overestimation. To comfortably pedal that for 5+ hours, the cyclists threshold should be 3.5 - 4 w/kg, which is higher than that of most bikepackers (pointy end of ultradistance racers excluded) - closer to the range of competitive cyclists. I'd be with you in the uphill case - 2w/kg are produced when going uphill a 5% slope. But on the flat road, your results could be a bit misleading. That being said, your content is fantastic and I really appreciate the effort in sharing your knowledge! Cheers from Germany.
Here's something that may be unexpected: B&M's standlight functionality means that there is extra drag. When the light is "off," the standby capacitor is still being charged. It sounds silly, but when I added an independent switch from my dynamo hub to my Cyo IQ Premium, I could feel a relatively much bigger difference between the light being on and off vs. when I used the switch on the light itself, which was almost imperceptible.
That's an interesting observation. As 'anywhere roam' mentioned, I would've suspected that the capacitor would take a very minimal power draw once it was full...
I had some faulty cabling and I was surprised to discover I could feel when the connection was good vs. not. Once I installed the switch I did some testing after charging the standlight for over an hour and it was still very noticeable! I have wondered if it's unique to my specific light or if it's related to all of the B&M standlights. I do have an IQ-X on the way and will be checking it out.
The most massive disadvantage about dynamo's in general is......... the number of times I get stopped by people, especially those I work with, who have to tell me that I left my bike lights on. This year I decided that I am not going to say don't worry the bikes got a dynamo and in a few minutes the lights will switch off all by themselves and then as soon as I move the bike they will spring into life (while I'm thinking I told you this last year) - only to get looked at like I must be riding a bike using alien technology. Now I'm just saying don't worry they are old batterys and I'm running them down so I can get new ones cheap off Amazon. Best bike invention ever imho. I own 2 - a Shimano built into a set of Taylor Wheels and a SON in a set of Hunts glorious 29ers and fingers crossed I will own another SON pretty soon that I intend building into a 29er wheelset I got given for free with broken spokes that it took me 10 minutes to fix.
@@farikkun1841 To make it waterproof - any button that you put on a bicycle light is a possible place that water can get in and stop the light working. Before I upgraded to a hub dynamo I got through endless front and rear lights because their battery compartments or on off switch let water in and damaged the electrical circuit. Properly designed dynamo lights have no on off switch and instead use a capacitor to store power for about 5 to 10 minutes and then you can just walk away and leave the bike and the lights go off when the stored power runs out - but they light back up the instant you move the tyres and cause the dynamo to turn.... so in practicality they are always switched on and never need switching off. This is a lesson the people who designed the worlds loudest bicycle horn, called 'The Hornit', need to learn - I bought one a few months ago and on two occasions its ended up going off at 140db in pouring rain and the only way you can stop it is remove its batterys and the only way to do that is spend ages fiddling round trying to undo a tiny tiny tiny philips screw that holds the battery compartment shut and yet still allows water in..... if your going to make things that hang off a bicycle and they work with electricity then make them waterproof.
@@farikkun1841 My commuter bike has an on of switch for the lights. I leave them on permanently, just to be seen better by cars. The drag you get is not noticable, and I'd rather spend some money on replacing the LEDs every few years than get hit by a car.
Great video! Thank you for your research! I've got a Son hub paired with a Sinewave cycles Beacon light and charger. I've always been curious about the drag. Thank you!
Sturmey-archer used to claim there dynohub added no friction. The vintage stuff Raleigh/SA made was always very understated but a friend told me you could feel the difference. My guess is that a 1.8W used by the lights would require 0.45 more power due to copper losses and nothing much more for magnetising and eddy current losses?
Not that nerdy at all, in my opinion - I found exactly what I was looking for. As I'm only occasionally biking in the city, mostly during daylight, I will use a battery light. I do understand though that a dynamo is attractive for people who want to use for more than just the light and regularly. What surprised me a little was that the SP dynamo is so much worse than a SON by the way.
Interesting results. Thanks. My back of the envelop analysis would go like this. A 2.4A USB port uses 12W of power and you'd add ~5W for the inefficiency of the dynamo to get a 5-17W reduction in power. Your light cyclist produces 120W and will have 103-115W remain to move the bike. That is 86-96% of the power available without the dynamo. Your heavy cyclist produces 180W and will have 163-175W remain to move the bike. That is 91-97% of the power available without the dynamo. How much of the power loss translates to speed loss is, as you say, depending on many factors. The results that you saw is within the expected theoretical values above. For lights, high efficient LED lights are around 85-100 lumen per W. How much power that you lose will depend on how bright the lights are. Better quality dynamo would reduce the 5W power loss but would not do any thing for the loss from the USB or light.
I love and respect all your technical stuff. Thanks for sharing your research and interpretations. However I have a really hard time keeping up with what you're saying and simultaneously keeping up with your data visuals, e.g. charts. By the time I've figured out that the chart labels are in another language, you cut away to a different scene. On my device it is really cumbersome to stop, find the few frames of video and start again. I would prefer you leave the data up longer and perhaps use live pointers to show what you're describing.
There is a lot of cover and I don't want to make my videos long. I always say the important details from the data, so the visuals are really just here for if you want to come back and dive deeper. Alternatively, there is always a written version on CyclingAbout.com.
I wonder if you could do some kind of set up where the dynamo kicks in on max power when going downhill, or braking, to blast-charge a Li battery or capacitor of some sort - that way it won’t slow you down at all as it will be effectively mopping up power you’re otherwise wasting in braking? A bit complex I know but a proper project for us bike-geeks!
I find power output at typical riding speeds is much more important than a tiny amount of extra drag. On my bikepacking bike, even with fast tyres, I do not notice the extra drag from my Shimano hub. Turn lights the off and stop recharging, and I do not notice any drag. The lights off drag is tiny compared to a full load drag too! And full load drag seems like nothing! And the Shimano hub makes the most power at typical riding speeds. Which is useful as I get more light on low-speed climbs and my gadgets charge up quicker. Is why I prefer Shimano to Son. Mine has lasted a long time, and I do not need to send a wheel back to Son to get the hub completely rebuilt. Just buy another Shimano hub for cheaper than Son charges for a rebuild and it arrives the next day. Fresh spokes and a fresh strong wheel build. The Shimano hub has dura-ace seals in it. Ridden moving through UK mud and puddles. Inc. the recent very wet weather, endless puddles. It just keeps going.
There are dynamos and accessories to charge your devices/phone through USB. Nice! I have not seen that before, I somewhat feel old just learning about this now.
I hadn’t thought about a dynamo setup until now. For me I want to tour around the state creating images and it would be one way to charge my phone or run a light at night. I’m. Not in a hurry so I am not worried about time. Besides they sound like they have less resistance than the old wheel generators.
The other problem is they just are not bright enough. My rechargeable headlight puts out 1600 Lumens at the highest setting. But my light has five settings, Low, Medium, high - 1600 Lumens and two different speeds of flashing. Yes, I have to keep it charged, but I also carry two batteries.
Great posting. But i wonder whether you heard of a different dynamo based on the old technology: It is called "VELOGICAL". bASED IN THE OLD SYSTEM (WHEEL drag). They are made by a german co. in Cologne. worth checking into, specially if you don't need a different hub. The cost is about 150 uros Thank you for detailed info and my admiration for what you do
I use the SON dynamo hub, actually I have three in total. I got my first about fifteen years ago. It has been used extensively and it runs and looks like brand new today. The SON hubs are pricey but I think they are very well worth it.
Their price is also "great" :-( As far as I've seen SON hubs are a bit lighter than Shimano so the weight penalty compared to non-dynamo hubs is reduced. That also reduces time loss uphill a bit.
Ha, was wondering that myself for a long time! However, if you put the increase of safety in the equation, than the dynamo hub always wins as batteries tend to run out of juice in the worst moments...
Alex, I am curious how you use this information to inform charging strategies while riding. For example, do you turn off your charger when climbing or facing a headwind and turn it on when going downhill or on flats?
I don't have a charging strategy, I just plug things in when they're running low on power. I just like tinkering with the numbers to entertain my intellectual curiosity! 😅
He did a horrible job explaining that a load placed on the hub varies by accessories. The larger the power draw the higher the 'drag' due to the magnetic field that increases in relation to the load.
I have Rohloff/Son 28-Edelux front and rear set ups on my touring bikes. I'm prepared to throw away some efficiency in favour of reliability, safety and good light on tap. On a long ride I count kilograms, not grams when kitting out anyhow. So why fuss about a few percentage points of drag?
I had once a dynamo hub on my trekking bike used for commuting. However, the usually used rear and front lights were not really reliable, the cables and connections corroded easily, and the lights were not really water proof. Now I use a 36 V light (powered by the E Bike battery) and a AA battery powered one on my E bike, and AA battery powered ones on my other non electric bikes. Of course you have to change batteries from time to time (I use rechargeable NiMh ones), but they are now more reliable than the old one. I use the bikes for sport and commuting, but not for crossing whole countries ;-)
I know, my Shimano hub produces more power at typical riding speeds while touring than any other hub. And I simply do not notice the extra drag with lights on/off, even while charging with lights on. All this analysis, and saying small percentage points matter - when in the real world they do not.
Nice number crunching. Sadly the chargers are all well outside my budget. Thankfully you can get a half decent dynamo lighting setup for city commuting at reasonable prices.
Also: I don’t think I could keep going for an hour on a hill steep enough that it had me down to 8kph. So at that point, any lost speed due to a dynohub is a moot point. Plus, at that speed, I have difficulty not wobbling, especially with a loaded bike. I think my minimum speed for good balance is about 6mph (~10kph). Probably something I need to work on.
I did tours for over 30 000km up to now and in 3weeks time I am leaving on anothe 4 000km tour....to be honest...you dont need this ecpensive piece of equipment...rather buy good 4 season tent...that can cost up to a $1 000 ....you will never regret that.Or put a Rholoff Hub on your back wheel.This is just a nice to have...
I would have thought the slowing effect of a dynamo hub was unnoticeable with about 3 watts. You would notice it if you spun the wheel with the bike lifted it. I estimate my 3000 lumen and 7000 lumen lights to be around the 10-30 watt mark at full brightness, though I will measure with an ammeter. They run off of separate battery packs though 30 watts would be significant slowing on a dynamo hub. It might feel like the tyres are a bit low on air.
I love Dynamo lights. That said, I had a Son hub crack and now steer clear of them. The crack started at the inside corner of the tessellated joint between the two halves of the hub. Sharp internal corners are stress risers, and I think it's just a flawed design.
It seems to me that a battery would help. Why not a regenerative system that charges the battery on downhills and flats, and discharges the battery on the climbs in order to reduce resistance?
How about a dynamo hub with a switch+ powerbank? Turn the charger off for uphills/ flats and enable on downhills, where you have to brake either way, so you don't lose any time?
Quality looking hubs those Son’s,Shimano know a thing or two about dynamo hubs too at almost half the price,think SP do a hub that has changeable axle options from Qr to boost etc 🤔
Since many years I use the SON for travels and rides, can not feel the drag. I was even considering equipping my travel trailer with 2 dynamo wheels to charge a bigger power-bank (but it's only at the idea stage for now)
Thank you for the information. I have subscribed! Not concerned with time loss as much as reliable source for minimal devices NEXT year on the GDMBR NOBO, not racing. Is there a video where you specifically talk about your personal setup? Thanks!
I TRULY appreciate your research and effort in this video, but there is a question I have. From strictly the Shimano offerings, you picked the most powerful (and draggiest) and the one of the worst offerings in the 3D32. My question is, not a video, but if you want to that would be awesome, could you compare just Shimano dynamos for the average guy who doesn’t have $350+ to spend on a SON? We ALL KNOW SON dynamos are the best, I just would love to see a comparison on how the the Shimano offerings stack up against each other. Especially the S501, and if you had to rank all of Shimano dynamos, how would you rank them from top to bottom?
What I really need is usable USB be power at back country single track speeds (10 kmph or less). I tend not to hit enough of faster trail to keep up w/ my device needs on trails like the AZT or the Colorado Trail.
I really, really apreciate your well-researched content. An engineer myself, I had studied these curves in detail last summer and ended up buying the Lumi-Con P5, which is in the top league at the speed we bike travelers travel at and can be fitted with big enough buffer batteries to carry me through an evening in the tent too. But: at a third of the total cost of the Cinq device. Admitted, it's not as neatly packed into the stem though, but since I carry some sort of handlebar- or top tube bag anyway, it does not matter. Plus, the guy who makes them, a German physics Phd who goes by the name of Schrödinger, literally lives a nice Sunday afternoon bike ride from my house here in Berlin. This device is really worth checking out.
I see you're using the Plug5 Plus, which is what I'd like to get for myself too. There's been reports of major problems once it starts raining; have you had any such misadventure with it yet? Also, what would be your other charger recommendation instead of the Plug5 when there's no possibility to install it (fork with no hole for instance)?
Yeah, my charger has stopped working 2-3x since I got it. I just take the top cap off and dry it out in the sun and it comes back to life. But apparently, I got one of the first production units, and Cinq told me they have improved the waterproofing since. I'm currently waiting for a new unit, but for some reason you cannot ship batteries out of Germany currently?! I'd probably choose the NC-17 Appcon 3000 or Forumslader V5 if I had a full carbon fork.
@@Cyclingabout Nice to hear something is done regarding the waterproofing. I'm genuinely considering buying a specific fork just so I could use the Plug5. Thank you for your recommendations too, it's really appreciated. Your content never disappoints, thanks for everything.
I use the very same SON and cinq plug. I'm not too impressed by the power it provides to my Pixel 4 though. And that it turns down output when the lights are on (I'd rather cycle harder). It's not enough to keep the device charged during use. I'm close to replacing it with a more powerful external bank. (Plus solar if I ever find myself truly off the grid.) Would be curious about your thoughts on the best mobile charging setup!
You won't get much charge with the lights on; it's really one or the other. Are you using the Plug III or Plug5Plus?
Před 3 lety
@@Cyclingabout The 5 plus, because of the USB C connection. But even with the lights off, it can't keep up. I think a smartphone just draws in a little bit more then the device can provide.
@ You might have a faulty unit, or perhaps the Pixel has some weird stuff going on. You should be getting enough power with the Plug5! A $5 USB LCD Voltmeter can help diagnose whether your Plug5 is making the right amount of power. I'd recommend plugging one in and seeing if you're getting the full 5V/0.5A at 12kph and 5V/0.9A at 20kph.
I find power output at typical riding speeds is much more important than a tiny amount of extra drag. On my bikepacking bike, even with fast tyres, I do not notice the extra drag from my Shimano hub. And the Shimano hub makes the most power at typical riding speeds. Mine has lasted a long time, and I do not need to send a wheel back to Son to get it completely rebuilt when it finally fails. Just buy another hub for cheaper than Son charges for a rebuild. The Shimano hub has dura-ace seals in it. Ridden mtbing through UK mud and puddles. Inc. the recent very wet weather, endless puddles. It just keeps going.
At least you can charge your Pixel 4 ;-) My USB-Werk can't charge my Samsung phone with USB C but I didn't check what actually happens with a scope or voltmeter. It does work with a camera (Micro USB), it did charge the phone I had before (also Micro USB) and I also tried it for a few kilometers with a switched off iPhone 8. Maybe a powerbank between charger and phone will help? But even if that works it's more stuff and more cables but on the other hand I can still charge on bikes without dynamo hubs or when I switch over to lights. I've installed a switch and wiring on my touring bike with positions lights/offcharger.
Would it make sense to have a hybrid dynamo/battery system and charge the battery in the downhills? How about engaging the dynamo automatically when braking? The descent of a big mountain pass is easy to spot and the dynamo can be turned on manually, but what about automatic detection of downhills? It could be optimized so that you could get the lights at night but the drag is minimized.
I wonder how much of drag is produced by the bearing itself and how much it could be affected by poor bearing adjustment from the factory. I found that a lot of shimano hubs were set to a too high bearing load. With quick release hubs and especially with hollow aluminium axles you allways want some play in the bearing setup, which then will be erased by the load of the quick release skewer, when build into the frame.
If you look at the hub drag graph without anything connected, the data suggests only 0.5 watts between best and worst-performing hubs. So the bearing variation is likely 5-10% of the total resistance with a light or charger connected.
If you want to go DEEP down the dynamo rabbit hole, jump on my website. You'll find a crazy amount of info on dynamo hubs, lights, USB chargers, wiring, batteries and more: www.cyclingabout.com/category/equipment/bike-equipment/dynamo/
Will do so. Thank you so much for your reply.
So what happens when you put them onto a mid drive electric bike?? Could they be used to charge the battery?
@@MrJturner74 🤦♂ If you only turned it on for downhills when the engine wasn't engaged you could maybe extend your range by 50m or so...
@@MrJturner74 don't electric bikes already have some kind of regen using the same motor-generator that powers the wheels?
@@confusedredditor1660 Only the stupidly expensive ones.
This guy doesnt do videos for the money or fame, in his reviews its just pure passion. Love Your work sir 😎👍💪
I appreciate that! Yep, bikes 'n travel are my two biggest passions. 🥰
@@Cyclingabout I run a Rohloff on both of my bikes. I love the sensation of direct drive with this hub. And I got them cheap from German 2nd hand market. On one bike I have a SON dynamo and the cheapest Shimano dynamo on the other. Cant complain on either one of them, except that the SON has bare metal connectors which oxidized and I had to replace the lower part of the wiring (so a win for the Shimano here).
@@peroperic3692 Interesting, I've never had that happen to any of my SON connectors!
@@Cyclingabout yeah, I accidentally squeezed the wire ends when taking out the front wheel, only to find out the light system is not working any more when I reinstalled the wheel. I unwrapped the wires (cut the housing) and the wires were green on the inside. I had some pieces of copper wire laying arround and just replaced this part of wire without soldering and put some heat shrink tubing over it. It works like a charm now. But this would be hard to fix on an expedition without the wire.
Pure passion, yep, but man (or even cyclist) does not live by passion alone! A bit of donor money helps fuel the passion. His reviews are the embodiment of scientific method. In equipment alone they must cost a bit.
Very interesting comparison. Previous to this, the two data points I was going off of (and why I have a dynohub) were:
1: my SON dynohub, when off, has less resistance than all but the very best racing hubs. We measured this by: flip the bikes over, give the wheels an equal-force spin, and then see how long until the wheel stops spinning, the bearings and construction are so much better in the SON hub than in most non-dynamo front hubs that it will spin longer, despite the added magnetic resistance. It just goes and goes and goes. And that certainly matches my on-bike perceptions: when the hub is off, I don’t feel a thing, and I can coast a long time if I’m in a good tuck.
2: I definitely notice the dynohub kick in. I have automatic lights, so it sometimes turns on in the middle of a ride, like when I go under a bridge. That said, the resistance with the lights on is still /way/ less then the semi-knobby tires I use in winter, and the difference between dynohub on and dynohub off is also much less noticeable than the difference between tires at 60 psi and same tires at 80 psi. Mostly, I notice the subtle vibrational hum coming up through the handlebars, not any additional resistance.
Best comment
Very nice video. One minor point. At the end of the video you say the Cyo headlight, introduced about 12 or 13 years ago is half the brightness of the IQ-X, which is true. However the Cyo Premium, which was introduced 7 or 8 years ago is 80 lux, vs 100 lux for the IQ-X. So anyone buying a current Cyo headlight is most likely buying a Cyo Premium, which is almost as bright as the IQ-X. The difference is enough to be noticeable if you're riding side by side and have the lights aimed exactly the same, vertically. But even a small difference in aiming the light will have a more significant difference in the beam's brightness on the road.
That being said, if you're riding in traffic at night in the rain, you never have enough light!
Peter J White
Peter White Cycles LLC
Compared to my ancient side-friction dynamo on my old bike, the hub dynamo always wins.
Yes but you could disengage it when not needed so you had no drag at all
@@Boss_Tanaka in my own experience the hub dynamo drag is negligible when it is not powering anything
@@Boss_Tanaka Completely neglectable if you don't have your lights turned off.
More importantly: When you are actually riding in the dark, the old side friction Dynamo REALLY slows you down. If you regularry ride in the dark, they are to crappy to use.
@@sagichdirdochnicht4653 And from my childhood memories it'll also let you down at times when the tyres get wet, but I must admit that they were maybe not always perfectly aligned or in the best state of maintenance. That poor efficiency and then also powering an incandescent bulb is something I really don't miss these days.
@@Boss_Tanaka But bottle dynamos wear out after one winter
Nerd out to your [our] heart’s content! Good real world information from someone who knows-
With a little tiny bit of drag you get to see more on the rides 😉
I love my SON with the Edelux and the B&M E-Werk on my Fatbike.
And I have to wait for my buddy all the time anyway, so that drag does not bother me at all!
Exactly! The extra drag is a BENEFIT not a COST
THIS is awesome and very informative. Will be watching your videos a lot.
Awesome, thank you!
Idk how I have missed this channel. Great video and certainly gives me food for thought. I am just thinking of using it to charge my battery banks. Seems more dependable than using my solar wing and hoping for good weather. Thanks for the well researched info. Ride safe!
Depth of research, crisp and clear description, and pure, unadulterated passion = a treat of a video. Thanks!
Thanks for more great content, Alee! I've always been curious about just how much of a difference dynamos make. It's surprising how many ultra racers use them given that overnight time penalty you mentioned! Guess that's another reason to sleep at night 🤣
That’s still less time lost than if when you do sleep it isn’t near a charger though
And still less time than spending a week in the hospital or eternity at the graveyard.
In my city, we have a bike share system and all of the bikes there use Hub Dynamos to power the integrated lights, I don't really have an issue using them and having the lights is a great safety feature
Really interesting, I'm just getting the parts together to rebuild an old bike from my shed to use as a commuter and now think that a dynamo hub and lights will be the ideal answer for me.
As always, another superbly researched and presented video. Your work is very much appreciated and I thank you broadening my cycling knowledge!
You are very welcome. I'm happy I can make videos about topics that are seldom covered.
Your videos are very well made. Your attention to detail indicates to your professionalism.
You know the in and outs of cycling sir🙏
Dynamo on a bike make much more sense nowadays with high efficiency LEDs. I recall when using a two 6 V 10 W Sylvania halogen bulbs setup (the bulbs with 30 hours lifetime). While with the LED the dynamo uses 1.5% of the total pedal power, with the halogen illuminator I went up to 10% of pedal power (for the same luminous flux). For time critical runs, we added a 6 V 10 Ah lead-acid battery, which provided 2 hours of light at 20 Watts, or 4 hours at 10 Watts.
Thanks for the video...
Awesome. I opted for the B&M IQ X and Son hub :D Holy moly. this is a detailed report. Thank you!
Love my son and my klite. First real test was the Pioneer 400 in September and it worked flawlessly and I easily charged stuff as I rode. Keep needing-out!
Good choice!
J'apprécie vos analyses dans leur pertinence et caractère scientifique.
Bravo et merci, monsieur.
Just speak english.
@@bypander801 Googlize: it's not insurmountable...
Thanks for sharing this data. If I were riding something like the TCR, I’d be tempted to switch off the dynamo when climbing, and just use some small battery lights, and then switch the dynamo back on at the top of the hill. Interesting.
Yaaaay, geeky numbers make the best videos! Thanks!
Another great review, it’s interesting to see the data... I currently use a Son28, K-Lite set up, so far, supper happy with it. Look forward to further videos from you.
Great to hear!
That's awesome! Much less drag than I expected
My son died from high wattage...
I'm sorry to hear that.
It's all good, I'll replace it tomorrow.
Very interesting -- thanks for doing the hard work of crunching the numbers!
Hey, great video, much needed info. Based on this video, the findings here I went with the Son 28. The only issue for me will be on Audax rides. I ride a Thorn Mercury which I also use for tours. For shorter Audax I had another wheel build with a normal hub. It was more for weight reasons. It's far easier for my legs to use USB lights, I take another set that are charged. Many riders still run the sun 28 on audax.
This was a great review and also accommodated for the 90kg riders which is a great amount of data reviews.
Thanks
Nice video. Your recent article on rim dynamos was interesting too. It would be interesting to see a rim version of this video with comparison to hub. Pedalec should be more efficient. With caveat around mud.
I've asked for some more information/numbers from the rim dynamo manufacturers, hopefully, I can make a video soon with their data.
I can tell you from experience going back a while, you can feel a rim dynamo very distinctly. Back in the olden days of crap batteries and bulbs the generator was reliable and ready when you needed it. When you flipped the generator off your bike felt like a rocket.
@@stevek8829 The latest ones are different! www.cyclingabout.com/rim-dynamos-can-now-generate-more-power-than-hub-dynamos/
I've always wondered about the effects of electrical loading on dynamo drag. The ones I've tried have been the flip on your tires type and they make noticeable drag.
Tyre dynamos aren't great. Even the best possible ones are making 10+ watts of resistance at 15KPH, which is 2-3x more drag than the best dynamo hubs.
Thanks for the reviews and information, today things cost so much and there are so many choices, not always easy to try them all.
Great video, thanks a lot! I do think though that you overestimate the w/kg output of the average bikepacker. This number will vary massively across cyclists of course, but I do think that 2 w/kg average for bikepacking is quite a big overestimation. To comfortably pedal that for 5+ hours, the cyclists threshold should be 3.5 - 4 w/kg, which is higher than that of most bikepackers (pointy end of ultradistance racers excluded) - closer to the range of competitive cyclists.
I'd be with you in the uphill case - 2w/kg are produced when going uphill a 5% slope. But on the flat road, your results could be a bit misleading.
That being said, your content is fantastic and I really appreciate the effort in sharing your knowledge! Cheers from Germany.
Here's something that may be unexpected: B&M's standlight functionality means that there is extra drag. When the light is "off," the standby capacitor is still being charged.
It sounds silly, but when I added an independent switch from my dynamo hub to my Cyo IQ Premium, I could feel a relatively much bigger difference between the light being on and off vs. when I used the switch on the light itself, which was almost imperceptible.
Interesting. I would have thought once the capacitor was charged the drag would lower but maybe there are more losses.
That's an interesting observation. As 'anywhere roam' mentioned, I would've suspected that the capacitor would take a very minimal power draw once it was full...
I had some faulty cabling and I was surprised to discover I could feel when the connection was good vs. not. Once I installed the switch I did some testing after charging the standlight for over an hour and it was still very noticeable!
I have wondered if it's unique to my specific light or if it's related to all of the B&M standlights. I do have an IQ-X on the way and will be checking it out.
My Light alone is supposed to draw 13W. It is definitly noticable when I turn it on.
Nice video! Definitely have a dynamo setup on my mind for 2021 bikepacking build!
Go for it!
The most massive disadvantage about dynamo's in general is......... the number of times I get stopped by people, especially those I work with, who have to tell me that I left my bike lights on. This year I decided that I am not going to say don't worry the bikes got a dynamo and in a few minutes the lights will switch off all by themselves and then as soon as I move the bike they will spring into life (while I'm thinking I told you this last year) - only to get looked at like I must be riding a bike using alien technology. Now I'm just saying don't worry they are old batterys and I'm running them down so I can get new ones cheap off Amazon.
Best bike invention ever imho. I own 2 - a Shimano built into a set of Taylor Wheels and a SON in a set of Hunts glorious 29ers and fingers crossed I will own another SON pretty soon that I intend building into a 29er wheelset I got given for free with broken spokes that it took me 10 minutes to fix.
I get hassled about my lights all the time too. 😅
why ur light dont have on/off switch?
@@farikkun1841 To make it waterproof - any button that you put on a bicycle light is a possible place that water can get in and stop the light working. Before I upgraded to a hub dynamo I got through endless front and rear lights because their battery compartments or on off switch let water in and damaged the electrical circuit.
Properly designed dynamo lights have no on off switch and instead use a capacitor to store power for about 5 to 10 minutes and then you can just walk away and leave the bike and the lights go off when the stored power runs out - but they light back up the instant you move the tyres and cause the dynamo to turn.... so in practicality they are always switched on and never need switching off.
This is a lesson the people who designed the worlds loudest bicycle horn, called 'The Hornit', need to learn - I bought one a few months ago and on two occasions its ended up going off at 140db in pouring rain and the only way you can stop it is remove its batterys and the only way to do that is spend ages fiddling round trying to undo a tiny tiny tiny philips screw that holds the battery compartment shut and yet still allows water in..... if your going to make things that hang off a bicycle and they work with electricity then make them waterproof.
@@farikkun1841 My commuter bike has an on of switch for the lights. I leave them on permanently, just to be seen better by cars. The drag you get is not noticable, and I'd rather spend some money on replacing the LEDs every few years than get hit by a car.
Very helpful. I’ve been using a Sun hub on our Rohloff equipped tandem, and I’ve lwondered how much extra work it required of us.
very intresting. like your scintific approach. thanks for t his vidio. regards paul.
Great video! Thank you for your research! I've got a Son hub paired with a Sinewave cycles Beacon light and charger. I've always been curious about the drag. Thank you!
Sturmey-archer used to claim there dynohub added no friction. The vintage stuff Raleigh/SA made was always very understated but a friend told me you could feel the difference. My guess is that a 1.8W used by the lights would require 0.45 more power due to copper losses and nothing much more for magnetising and eddy current losses?
More drag than I thought! Better than charging stupid lights all the time though...
Not that nerdy at all, in my opinion - I found exactly what I was looking for. As I'm only occasionally biking in the city, mostly during daylight, I will use a battery light. I do understand though that a dynamo is attractive for people who want to use for more than just the light and regularly. What surprised me a little was that the SP dynamo is so much worse than a SON by the way.
This one of those "likes instantly" videos ;)
Interesting results. Thanks.
My back of the envelop analysis would go like this. A 2.4A USB port uses 12W of power and you'd add ~5W for the inefficiency of the dynamo to get a 5-17W reduction in power. Your light cyclist produces 120W and will have 103-115W remain to move the bike. That is 86-96% of the power available without the dynamo. Your heavy cyclist produces 180W and will have 163-175W remain to move the bike. That is 91-97% of the power available without the dynamo. How much of the power loss translates to speed loss is, as you say, depending on many factors. The results that you saw is within the expected theoretical values above.
For lights, high efficient LED lights are around 85-100 lumen per W. How much power that you lose will depend on how bright the lights are.
Better quality dynamo would reduce the 5W power loss but would not do any thing for the loss from the USB or light.
Your research 🔬 is so great it’s everything we are asking
I love and respect all your technical stuff. Thanks for sharing your research and interpretations. However I have a really hard time keeping up with what you're saying and simultaneously keeping up with your data visuals, e.g. charts. By the time I've figured out that the chart labels are in another language, you cut away to a different scene. On my device it is really cumbersome to stop, find the few frames of video and start again. I would prefer you leave the data up longer and perhaps use live pointers to show what you're describing.
There is a lot of cover and I don't want to make my videos long. I always say the important details from the data, so the visuals are really just here for if you want to come back and dive deeper. Alternatively, there is always a written version on CyclingAbout.com.
I wonder if you could do some kind of set up where the dynamo kicks in on max power when going downhill, or braking, to blast-charge a Li battery or capacitor of some sort - that way it won’t slow you down at all as it will be effectively mopping up power you’re otherwise wasting in braking? A bit complex I know but a proper project for us bike-geeks!
I find power output at typical riding speeds is much more important than a tiny amount of extra drag. On my bikepacking bike, even with fast tyres, I do not notice the extra drag from my Shimano hub. Turn lights the off and stop recharging, and I do not notice any drag. The lights off drag is tiny compared to a full load drag too! And full load drag seems like nothing! And the Shimano hub makes the most power at typical riding speeds. Which is useful as I get more light on low-speed climbs and my gadgets charge up quicker. Is why I prefer Shimano to Son. Mine has lasted a long time, and I do not need to send a wheel back to Son to get the hub completely rebuilt. Just buy another Shimano hub for cheaper than Son charges for a rebuild and it arrives the next day. Fresh spokes and a fresh strong wheel build. The Shimano hub has dura-ace seals in it. Ridden moving through UK mud and puddles. Inc. the recent very wet weather, endless puddles. It just keeps going.
This is super rad! Thanks so much for making and sharing this video.
There are dynamos and accessories to charge your devices/phone through USB. Nice! I have not seen that before, I somewhat feel old just learning about this now.
Thanks a lot for sharing your precious experiences.
Awesome video. Thank you.
i have learnt so muvh through this channel thanks so much :)
another great production. thank you.
Fantastic info! Love the geeking out on this material. 👍
I hadn’t thought about a dynamo setup until now. For me I want to tour around the state creating images and it would be one way to charge my phone or run a light at night. I’m. Not in a hurry so I am not worried about time. Besides they sound like they have less resistance than the old wheel generators.
You don't notice the dag at all, at least I don't. A better quality tyre would make far more different and more than offset it.
I did a dynamo setup on the cheap: Shimano Alfine hub and Cateye Stvetso lights from China.
Nothing wrong with that setup! It's VERY common in both Japan and China.
@Cyclingabout. Do check out the NEW Klite Ultra Low Drag road-specific model. Much better.
That was fascinating. I have no idea how to connect a SON hub to a bike though.
The other problem is they just are not bright enough. My rechargeable headlight puts out 1600 Lumens at the highest setting. But my light has five settings, Low, Medium, high - 1600 Lumens and two different speeds of flashing. Yes, I have to keep it charged, but I also carry two batteries.
Great posting. But i wonder whether you heard of a different dynamo based on the old technology: It is called "VELOGICAL". bASED IN THE OLD SYSTEM (WHEEL drag). They are made by a german co. in Cologne. worth checking into, specially if you don't need a different hub. The cost is about 150 uros Thank you for detailed info and my admiration for what you do
Yes, I have an article on rim dynamos here: www.cyclingabout.com/rim-dynamos-can-now-generate-more-power-than-hub-dynamos/
Thanks for this video man!
Would like to see the comparison with the pedal cell dynamo included.
Thanks for the video.
I use the SON dynamo hub, actually I have three in total. I got my first about fifteen years ago. It has been used extensively and it runs and looks like brand new today. The SON hubs are pricey but I think they are very well worth it.
I agree. Everything about the SON is great - the efficiency, reliability, bearing life and finish.
Their price is also "great" :-(
As far as I've seen SON hubs are a bit lighter than Shimano so the weight penalty compared to non-dynamo hubs is reduced. That also reduces time loss uphill a bit.
Ha, was wondering that myself for a long time! However, if you put the increase of safety in the equation, than the dynamo hub always wins as batteries tend to run out of juice in the worst moments...
awesome video GOOD JOB!
Alex, I am curious how you use this information to inform charging strategies while riding. For example, do you turn off your charger when climbing or facing a headwind and turn it on when going downhill or on flats?
I don't have a charging strategy, I just plug things in when they're running low on power. I just like tinkering with the numbers to entertain my intellectual curiosity! 😅
Those are some of the coolest gadgets I've seen.
how the dynamo resistance can vary depending on power used?
what i know from car alternator is it has clutch mechanism. dunno bout the bike dynamo
He did a horrible job explaining that a load placed on the hub varies by accessories. The larger the power draw the higher the 'drag' due to the magnetic field that increases in relation to the load.
alternators have diodes not a clutch. your a/c compressor has a clutch.
@@fredricknietzsche7316 how diode affect alternator drag when battery 20% vs 100%
@@fredricknietzsche7316 alternators have clutch pulley
I have Rohloff/Son 28-Edelux front and rear set ups on my touring bikes. I'm prepared to throw away some efficiency in favour of reliability, safety and good light on tap. On a long ride I count kilograms, not grams when kitting out anyhow. So why fuss about a few percentage points of drag?
I had once a dynamo hub on my trekking bike used for commuting.
However, the usually used rear and front lights were not really reliable, the cables and connections corroded easily, and the lights were not really water proof.
Now I use a 36 V light (powered by the E Bike battery) and a AA battery powered one on my E bike, and AA battery powered ones on my other non electric bikes. Of course you have to change batteries from time to time (I use rechargeable NiMh ones), but they are now more reliable than the old one.
I use the bikes for sport and commuting, but not for crossing whole countries ;-)
I know, my Shimano hub produces more power at typical riding speeds while touring than any other hub. And I simply do not notice the extra drag with lights on/off, even while charging with lights on. All this analysis, and saying small percentage points matter - when in the real world they do not.
Nice number crunching. Sadly the chargers are all well outside my budget. Thankfully you can get a half decent dynamo lighting setup for city commuting at reasonable prices.
Also: I don’t think I could keep going for an hour on a hill steep enough that it had me down to 8kph. So at that point, any lost speed due to a dynohub is a moot point. Plus, at that speed, I have difficulty not wobbling, especially with a loaded bike. I think my minimum speed for good balance is about 6mph (~10kph). Probably something I need to work on.
Dynamo hub+lights and USB charging port and internal gearing is my dream set of improvements for my bike.
It's a good dream to have! I think they genuinely improve the experience of bike travel. 🙏🏼
Your analysis are the best!
Thanks!
fantastic review thanks
I did tours for over 30 000km up to now and in 3weeks time I am leaving on anothe 4 000km tour....to be honest...you dont need this ecpensive piece of equipment...rather buy good 4 season tent...that can cost up to a $1 000 ....you will never regret that.Or put a Rholoff Hub on your back wheel.This is just a nice to have...
I would have thought the slowing effect of a dynamo hub was unnoticeable with about 3 watts. You would notice it if you spun the wheel with the bike lifted it.
I estimate my 3000 lumen and 7000 lumen lights to be around the 10-30 watt mark at full brightness, though I will measure with an ammeter. They run off of separate battery packs though 30 watts would be significant slowing on a dynamo hub. It might feel like the tyres are a bit low on air.
I love Dynamo lights. That said, I had a Son hub crack and now steer clear of them. The crack started at the inside corner of the tessellated joint between the two halves of the hub. Sharp internal corners are stress risers, and I think it's just a flawed design.
It seems to me that a battery would help. Why not a regenerative system that charges the battery on downhills and flats, and discharges the battery on the climbs in order to reduce resistance?
I love nerdy videos 📼! More please. 👍☮️🌞🚴🚵
How about a dynamo hub with a switch+ powerbank? Turn the charger off for uphills/ flats and enable on downhills, where you have to brake either way, so you don't lose any time?
Quality looking hubs those Son’s,Shimano know a thing or two about dynamo hubs too at almost half the price,think SP do a hub that has changeable axle options from Qr to boost etc 🤔
Since many years I use the SON for travels and rides, can not feel the drag. I was even considering equipping my travel trailer with 2 dynamo wheels to charge a bigger power-bank (but it's only at the idea stage for now)
Good video 👍
Thank you for the information. I have subscribed! Not concerned with time loss as much as reliable source for minimal devices NEXT year on the GDMBR NOBO, not racing. Is there a video where you specifically talk about your personal setup? Thanks!
I TRULY appreciate your research and effort in this video, but there is a question I have. From strictly the Shimano offerings, you picked the most powerful (and draggiest) and the one of the worst offerings in the 3D32. My question is, not a video, but if you want to that would be awesome, could you compare just Shimano dynamos for the average guy who doesn’t have $350+ to spend on a SON? We ALL KNOW SON dynamos are the best, I just would love to see a comparison on how the the Shimano offerings stack up against each other. Especially the S501, and if you had to rank all of Shimano dynamos, how would you rank them from top to bottom?
What I really need is usable USB be power at back country single track speeds (10 kmph or less). I tend not to hit enough of faster trail to keep up w/ my device needs on trails like the AZT or the Colorado Trail.
Battery or solar is the only real solution for sub-10KPH.
Amazing video , it will be great if you can add a link to the tools you are using it will be great
I really, really apreciate your well-researched content. An engineer myself, I had studied these curves in detail last summer and ended up buying the Lumi-Con P5, which is in the top league at the speed we bike travelers travel at and can be fitted with big enough buffer batteries to carry me through an evening in the tent too. But: at a third of the total cost of the Cinq device. Admitted, it's not as neatly packed into the stem though, but since I carry some sort of handlebar- or top tube bag anyway, it does not matter. Plus, the guy who makes them, a German physics Phd who goes by the name of Schrödinger, literally lives a nice Sunday afternoon bike ride from my house here in Berlin. This device is really worth checking out.
I'm glad to hear you're happy with the Lumi-Con. It's hard to beat the price-to-performance of it!
Thanks I really appreciate :)
I see you're using the Plug5 Plus, which is what I'd like to get for myself too. There's been reports of major problems once it starts raining; have you had any such misadventure with it yet?
Also, what would be your other charger recommendation instead of the Plug5 when there's no possibility to install it (fork with no hole for instance)?
Yeah, my charger has stopped working 2-3x since I got it. I just take the top cap off and dry it out in the sun and it comes back to life. But apparently, I got one of the first production units, and Cinq told me they have improved the waterproofing since. I'm currently waiting for a new unit, but for some reason you cannot ship batteries out of Germany currently?!
I'd probably choose the NC-17 Appcon 3000 or Forumslader V5 if I had a full carbon fork.
@@Cyclingabout Nice to hear something is done regarding the waterproofing. I'm genuinely considering buying a specific fork just so I could use the Plug5.
Thank you for your recommendations too, it's really appreciated.
Your content never disappoints, thanks for everything.
Any idea how to compare using a dynamo and a charger to carrying the weight of a power bank and lights? even 500 grams add some cost
Thank you
I use the very same SON and cinq plug. I'm not too impressed by the power it provides to my Pixel 4 though. And that it turns down output when the lights are on (I'd rather cycle harder).
It's not enough to keep the device charged during use.
I'm close to replacing it with a more powerful external bank. (Plus solar if I ever find myself truly off the grid.)
Would be curious about your thoughts on the best mobile charging setup!
You won't get much charge with the lights on; it's really one or the other. Are you using the Plug III or Plug5Plus?
@@Cyclingabout The 5 plus, because of the USB C connection. But even with the lights off, it can't keep up. I think a smartphone just draws in a little bit more then the device can provide.
@ You might have a faulty unit, or perhaps the Pixel has some weird stuff going on. You should be getting enough power with the Plug5!
A $5 USB LCD Voltmeter can help diagnose whether your Plug5 is making the right amount of power. I'd recommend plugging one in and seeing if you're getting the full 5V/0.5A at 12kph and 5V/0.9A at 20kph.
I find power output at typical riding speeds is much more important than a tiny amount of extra drag. On my bikepacking bike, even with fast tyres, I do not notice the extra drag from my Shimano hub. And the Shimano hub makes the most power at typical riding speeds. Mine has lasted a long time, and I do not need to send a wheel back to Son to get it completely rebuilt when it finally fails. Just buy another hub for cheaper than Son charges for a rebuild. The Shimano hub has dura-ace seals in it. Ridden mtbing through UK mud and puddles. Inc. the recent very wet weather, endless puddles. It just keeps going.
At least you can charge your Pixel 4 ;-)
My USB-Werk can't charge my Samsung phone with USB C but I didn't check what actually happens with a scope or voltmeter. It does work with a camera (Micro USB), it did charge the phone I had before (also Micro USB) and I also tried it for a few kilometers with a switched off iPhone 8.
Maybe a powerbank between charger and phone will help? But even if that works it's more stuff and more cables but on the other hand I can still charge on bikes without dynamo hubs or when I switch over to lights. I've installed a switch and wiring on my touring bike with positions lights/offcharger.
Would it make sense to have a hybrid dynamo/battery system and charge the battery in the downhills? How about engaging the dynamo automatically when braking? The descent of a big mountain pass is easy to spot and the dynamo can be turned on manually, but what about automatic detection of downhills? It could be optimized so that you could get the lights at night but the drag is minimized.
it be nice to find a smart charger
so.it only ever pulls from the dynamo when the battery is under a certain threshhold
I wonder how much of drag is produced by the bearing itself and how much it could be affected by poor bearing adjustment from the factory. I found that a lot of shimano hubs were set to a too high bearing load. With quick release hubs and especially with hollow aluminium axles you allways want some play in the bearing setup, which then will be erased by the load of the quick release skewer, when build into the frame.
If you look at the hub drag graph without anything connected, the data suggests only 0.5 watts between best and worst-performing hubs. So the bearing variation is likely 5-10% of the total resistance with a light or charger connected.
Thinking about getting this for my new frameset
the drag is caused by eddy current losses in the dynamo hub. the more power you take the higher is the resistance.
thanks for this video!
Thank you! Great video!