IS The SRAM GXP The Worst Crankset In The World?
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- čas přidán 3. 11. 2019
- The GXP crankset featured in this video has been on 3 different bikes with 3 totally different bottom bracket types, ridden over 20,000 miles and never had any of the issues with bad fit, creaking, rattling or any other issues recently noted from a popular CZcams engineer.
In this video, I run through a process that I've found works well on most applications. - Jak na to + styl
Great job, Joey. Nicely presented. Stay classy.
Staying classy is always the goal. Thanks for your feedback!
a tip : watch series at flixzone. Me and my gf have been using them for watching all kinds of movies during the lockdown.
@Javier Cristiano Yea, been using Flixzone for since november myself =)
Do you have a link for the delrin spacers you were talking about? I have a feeling I will need these as there is some space on the drive side of the Force 22 cranks I am trying to install. They spin just fine and the non drive side is pressed against the gxp bb nicely but the drive side does not look flush. Thanks!!
Hey thanks for the video. I just picked up a used Niner handtail and im enjoying it a lot. My front crank gear had a bunch of wobble in it and luckily i could read GXP on the crank set. This video helped me learn how to take it apart. The 3 torx bolts on the back had loosened up a bit, i added lock washers (no clearance issues) should i add locktight?
Hi Joey, recently i have been trying to install a sram gxp crankset on bb386 frame(Time scylon); i have used a 2mm spacer on the drive side as instructed, it is necessary both from the stand point of chainring bolt not hitting the frame and via measuring the length of the crank arm spindle itself matching with the bottom bracket; the problem i have is that after installation, the chainring is just too far away from the front derailleur that it is impossible to shift from the small chainring to the big chainring; if i remove the 2mm spacer, it works fine, but there is a big risk that the chainring will rub the frame, have you encoutered this kindda problem before, and what is your suggestion on solving it? thanks in advance.
I've run GXP across multiple bikes and frames (threaded and pressed) and haven't had any issues.
Yeah, that's been my experience as well. Thanks for taking the time to leave feedback!
Hi Joey thanks for the video. One of Hambini's beefs was the variance when he measured the non-drive side's splines on the spindle. I have a pressfit 86 and worn 50T chainring that I want to replace. I have had my bearings out 3 times in 18 months. I ride alot in the rain and creaking has developed again, slight this time. What would you recommend to replace it. The tiagra crankset is not easy to find a single chainring plus i would like to go smaller (46T?). I am willing to look at other BBs. You seemed to think a 30mm spindle isn't as good? What mid priced BB have you liked? Thx.
Thanks Al
I don't know if Hambini fully understands the concept of how the GXP system actually works or not. The spindle spline area OD and the NDS bearing ID is irrelevant due to the fact that the bearing contact points are the beveled spindle shoulder and the crank arm. The bottom line is Hambini didn't get the NDS crank arm fully purchased on the spindle and blamed it on poor engineering. I tried to have a discussion with Hambini about it, but he mostly just called me names.
As far as your BB situation, unless you're wanting to switch crank manufacturers, your Shimano Tiagra is fine. You didn't mention if it's the 4700 model or 4600 or older. The 4700 chainrings are more expensive to replace and won't have as many size options as the 5 bolt 110mm bolt circle diameter of the 4600. If you have the 5 bolt version, there's quite a lot of aftermarket options. If you're looking for a lower gear range going from the 50 to a 46 chainring, a more cost effective route may be looking into a wider range cassette. That depends on what cassette you currently have though.
As far as your bearings go, I'd stick with a Shimano press fit BB. It's about as good as it gets for something mid range price wise. If you're looking for something with metal cups instead of plastic that threads together, Wheels MFG BB's are my favorite. They run about $74 amzn.to/2ydQSm3
Also riding in the rain can cause lots of creaks to appear that may not even be the bottom bracket. I made another video on some common things to check before getting into the bottom bracket: czcams.com/video/SR5_xUBipa0/video.html
Unless the bearings are really rough or notchy feeling or have excessive play, they're probably fine. I've had a Shimano BB on my crappy weather commuter for over a year and a half. That bike gets ridden mostly in rain or snow, dirt and gravel, gets washed about once a month (sometimes that in itself gets water into the bearings) and they still feel smooth as butter.
I wouldn't consider a 30mm spindle at all for your setup. You would need new cranks and a specialty 41mm OD bearing cup for a 30mm spindle. It would be expensive and way less durable than what you have now.
Thanks for your questions and feedback!
@@JoeyMesa xlnt ty. 4700. One creak was the crank arm, i took it off, cleaned and greased and it's gone. My creak currently has gone, i expect the temperature has had an effect. I already ride a 34T cassette and 36T on my gravel race wheels. I had a 42T but it broke my rear derailler as the wolftooth roadlink snapped in half during a rainy dirty race. I have the cassette on my mtb which is also 10 speed, which i like - that i can go back and forth, i have a goatlink on there and a clutch derailler, works fine. The Wheels bb is on my list, thanks for telling me your experience on that, i will prob go with that. $125 CAD. Next time i remove the cups i will take a look at the bearings. So the chain ring is the issue. Apparently there are 3 other cranks that are compatible that i could use the rings from - Ultregra I think and another. So I'll have to be patient on sourcing it. The small chainring is fine, the bigger one is getting pointed - plus it can take some dings. Ty
great! can you tell me the measurements of the thickness you used?
Joey what do you think of new SRAM dub? I think it's an aluminum spindle but same basic design. Hambini likely only gets problem cranks and stuff so he may be suffering from confirmation bias, I dunno. I wonder how long before Shimano's patent expires, didn't find much with a quick google search.
My initial opinion of SRAM DUB when it was first introduced was I thought it was redundant and wouldn't solve the issues that BB30/PF30 were plagued with. After installing quite a lot on new bikes being equipped with the system, my opinion changed to more neutral. Several months ago, I got a new bike that was equipped with the new SRAM Force AXS group, as well as a DUB crank/BB. I'm actually starting to really like it now. It's a gravel bike and I've got probably 3000+ miles on it so far. I use it to commute to work in all weather conditions, ride gravel and single track, and it hasn't made a peep since then.
I'm not sure why Hambini is so bitter. My day job is nothing but wrenching on bicycles of all types, and I've seen a LOT of problematic cranks and BB's. I can't really tell folks their bike has a problem because it's poorly engineered and it sucks, I just have to figure out how to make it work. It's always best to be on good terms with bike companies as they're generally willing to take care of you if there is a defect in their product. Going on epic public rants may be entertaining, but it isn't going to help your situation.
Shimano and SRAM both have their shortcomings, but I think overall, having them compete against each other makes both companies better.
Thanks for your question and feedback, I really appreciate it!
Joey Mesa
Hambini is prick!
He become popular because of the way he performs his pseudo-scientific/enginered videos
@@mikicastan maybe you should learn to spell before you comment
Can i use m8/m15 bolt in crank lock?in gxp spindle
At 5:39 it looks like you've got just as much radial play as the Hambini video. Tightening the NDS crank arm down as you have done is not going to center the bearing.
bearing is fixed from lateral compression or axle diameter grows during tightening ?
You have a good point, and that's something I thought about as well. I started looking a little closer at the spindle and one thing I noticed was that if you hold the bearing up against the shoulder of the spindle, the bearing won't move. I wondered if the shoulder was beveled instead of a squared off 90 degrees, and it is indeed machined with a small concave shaped bevel. Tightening the non drive side crank arm against the bearing will cause the bearing to center itself against the beveled portion of the spindle.
I made a video with some close ups of what I'm describing, but I feel like it's boring, so I haven't uploaded it.
The shoulder that the bearing rests against is beveled which centers the bearing.
Yup, that is exactly what I thought.
@@JoeyMesa Could you upload the video if you still have it? I always learn from your expertise.
I'm relatively new to bike maintenance so sorry if this is a dumb question. My bike has a SRAM Rival crankset with GXP bottom bracket. It spins very freely considering there's no play, even after a lot of miles in bad conditions, so in practice it's actually spinning much more smoothly than my other bike with Shimano HT2 preloaded enough to remove play. But recently when I was inspecting my bike with the SRAM crankset, just messing around with it to check for any looseness anywhere, I noticed if I put my weight on a pedal (bike on floor) I can see the crank arm flex inward quite a lot. It's probably always been that way, but visually it flexes more than I expected. I know frames and components flex, and that stiffness and compliance are things people want in different areas, but I was just surprised how much flex there is. I don't know what's normal. I can't tell if it's mostly the crank arm itself flexing, or if it's more the spindle pressing against the bearings radially. I don't feel play here, I just see elastic bending which I'm calling flex.
So I was gonna ask my local mechanic or a forum about what range of this is normal. But then I watched this and I noticed near the end you were checking for the same thing by squeezing the crank arms toward the chain stays with your hands. And it looked like a similar amount of movement for the force applied. When you do this, what are you checking for, i.e. how much movement is too much? Is this something GXP does more than other standards because of its asymmetry? After seeing this I have new appreciation for people's obsession with stiffness in the pedaling area. Otherwise I do like things supple.
It will vary with different manufacturers, models, and designs/crank materials, but they all flex if you push it in sideways like that. Some more than others, but it's totally normal. You just don't want it to flex and make contact with the chain stay.
I can add that my SRAM XO1 GXP crank and threaded BB setup is nightmare setup and bearing durability when compared to Shimano Hollowtech. Only feels smooth to spin initially when new GXP BB is installed but within 2-3 months the bearing is toasted, as in gritty and rough to spin. Always the same side bearings go bad. After watching Hambini video it came clear to me why I am going through so many GXP BB bearings.
I agree with you that GXP cranks are more difficult to set up correctly compared to Shimano hollow tech II cranks. However, I've literally installed thousands of GXP crank/BB configurations with great long term success. I've also seen many that were improperly installed and the resulting issues. I'm not going to speculate what your bearing issue is/was because I haven't worked on your bike. Watching Hambini is a poor example as he never follows through with the assembly. If the non drive side is not tight enough, you'll get play between the spindle/bearing interface. If you have too many or not enough spacers on the drive side, you'll smoke one or both bearings. It's a pretty simple system, but it stumps a lot of mechanics who don't understand or have much experience with GXP cranks and BB's.
Joey I followed GXP BB and XO1 crankset installation to per instrcution that came with the crankset. I've been wrenching my own bikes for 20 years now and I never had bearing go bad so fast on BB. I thought it might be SRAM GXP bearing qaulity issue so I went ahead and spent some extra coin on RWC brand GXP BB kits. It didnt matter. I cant be replacing BB bearing 3-4 times per every riding season. I gave up on XO1 crankset with GXP BB. It just collects dust now. Maybe some day I'll get brave give another try but what other method is to install this GXP setup other than it's own installation manual? I am using recomended spacers and torque setting as specified in the instruction manual.
@@JoeyMesa when you shim the drive side you're building it against instructions. You are effectively giving the drive side an axial load towards the centre and unload the axial load to the outside on the NDS. That may fix the design faults in the GXP bracket. But that is a botch entirely against the design by SRAM. Who apparently did that horrible set up witch all side loads on the NDS to avoid running afoul of Shimano patents. To conclude this line of argument: As I see it you are trying to say something is not bad by design because by changing what's bad in that design it isn't as bad any more.
@@geraldschenk I'm not shimming the drive side, I simply like to fill the void between the spider/drive side crank arm and the drive side bearing/dust cap, just enough to hold the dust cap in place. If there are too many spacers, it will sideload the drive side bearing as you say. When set up correctly, there is only a radial load on the drive side bearing, that is when the non-drive side crank arm is properly secured ( the part Hambini doesn't get right).
To conclude my argument: The Sram GXP is a good design but is susceptible to problems when incorrectly installed.
Joey Mesa å
The way I see it is that the wavy washer acts as a preload to the drive side bearing, at the same time loading the non drive side, so it becomes essentially the same as Shimano (which use the pre load method, just like a headset). My question is how can you measure the exact size of the shim required when working on the bike?(seems like it would take an extremely accurate measurement)
It depends on what type of frame the bottom bracket is designed. On a threaded BB with cups, the non drive side bearing is pretty secure in the cup, and in that case, honestly, you don't need any spacers or wavy washer unless it's an aftermarket BB that has a dust cap that rests against the drive side bearing. Some folks use an o-ring to keep the dust cap against the bearing, but the bearing doesn't need to be preloaded like a headset or a Shimano BB. The spindle is locked in place with the non drive side bearing sandwiched between the crank arm and the shoulder on the spindle. The drive side bearing only sees a radial load, so it doesn't need to be preloaded.
In the case of a bottom bracket like the bb90 on Trek bikes, you really need some spacers between the drive side bearing and the spider otherwise the non drive side bearing can migrate out of the frame and cause damage to the frame. You just have to experiment with the thickness of the spacer shims. You can get delin spacers .5mm thick, but ironically, Shimano has 24mm spindle spacers that are very thin for hollow tech II tandem stoker cranks.
@@JoeyMesa thanks for the reply. The way you explain the non drive bearing being locked in and doing both radial and axial load and drive side doing radial only is the same as the explanation given by Hambini. However I'm not sure I get the idea, is there something different with the bearings? The way I see it is that the NDS bearing would need to have absolutely zero axial play, or the crank will have play in it, even if it's locked in on the outer race (NDS)... Wouldn't a slight pre load still be necessary as is the case for any other type of BB bearing?
I've just replaced my 2x MTB-spec GXP crank and BB with a 1x GXP crank and a new BB. The old one has done 10K+ miles and had started to look a little "shark toothed". I fancied going 1x anyway, so I stuck with what was there originally, and why not? It just works. I haven't had any issues with slop either - mine nips-up perfectly and there's no play in the system. That said, there is a gap at the drive-side but still no play so I've just left it as a gap - I'm sure it's intended to be this way. Might just treat it as a service item and clean/grease it from time to time. I haven't bothered trying to shim mine. Oh, my BB is an English threaded one.
When I need to (next time), can I just replace the bearings or will I need to replace the whole BB shells too?
Yeah, I still stand by my opinion that when set up correctly, these things are very durable.
You could replace just the bearing cartridges, but for the money and the path of least resistance, it's way easier to just replace the thread in cups with the bearings in place.
Thanks for the feedback and the question!
I never had issues with the threaded GXP bearings myself but there is no question that Shimano has the superior system.
The shimano system is definitely easier to install, but I’ve owned and used both for thousands of miles, and durability wise, they’ve held up about the same for me.
Anyway, thanks for your feedback!
My brother... Help me out... I have a BB86 GXP, I am 85kg sprinter and I always hear some creeks. I use that wave washer on the drive side (sram red gxp 11spd crankset) Im afraid something could get damaged if I remove wave washer... Should I try?
The crank bolt on my SRAM GXP came loose and it wouldn't stay in after that as the threads were too worn. I bought a new bolt but when I tighten it, it causes the cranks to bind and not spin freely. This is at a very low torque, miles away from the recommended ~ 50 Nm. I guess the cranks are squashing the BB bearings (a BB 109) when I tighten the bolt up. I can't figure out why a new bolt would cause this though, any ideas? Perhaps the splines are worn and the cranks are riding too far up the axle? I bought an unbranded bolt but it is the same length and diameter as the original.
I think I’ve got a similar problem.
@@campagnol1 Mine was a used bike that had not been looked after. Presumably many miles of riding with a loose crank bolt. I replaced the whole crankset (and BB).
@@user-go8oj4dl4w yes, I’ve decided to replace my entire crank assembly as well and see what happens
I fully agree .
I had a creaking bb30 and brought it to a bike shop .
There they installed a wheels mfg bottom bracket .
After 6 month again creak , i took out the bottom bracket spacers myself and put locktite retaining compound between the wheels mfg and the bb30 aluminium innershell and finally the creak is gone .
As said here already after that take out the wave washer and some spacers of the cranck assemby and adjust untill everything is without play after tightening and running smooth
Also dont put all the spacers on 1 side , try to center the sram gxp assembly .
And now my sram red gxp runs smooth as hell.
I put also light sewing machine oil in the enduro bearings after flushing the old bearing grease out .
My bearings are 3 years old already but still fine
Hi Joe, very informative video thanks! I recently installed a SRAM GXP and SRAM RED crankset- with no spacers on a road bike- the crankset is not running smoothly- it is very stiff to turn- should I have used the spacers?
Threaded? Pressfit? If it is stiff to turn, most likely the spider is rubbing against something or the outside bearing to bearing measurement is too wide. With the cranks removed, the overall width of the bottom bracket with the bearings installed and dust covers in place should measure about 92mm. If it is more than a millimeter wider than this, you're getting excessive radial load on the bearings. Adding spacers would only make the matter worse.
@@JoeyMesa if i have width 95mm, what can i do?
I have gxp it ran fine but I feel some type of pull.. can I change gxp to bb Infinity?
GXP is the type of crank you currently have, so unless you switch crank types, you're locked into that type. BBinfinite is a bottom bracket manufacturer that makes many GXP type BB's. As a mechanic, I prefer a 2-piece type GXP such as those from Wheels Mfg. Much easier to install and maintain.
I'm having problems where the bolt keeps working loose, its happened about 5 or six times now. After watching this video I will take off the wavy washer, and try it again.
Thank you Sir, it was the creaking, GXP bottom bracket that drew me into this whole vortex of Hambini and then you. I mean I don’t know if Hambini is a good engineer or not, I certainly found his swearing and innuendo highly amusing to my juvenile sense of humour. Your approach I found more convincing, and I’m grateful cos I’m stuck with GXP bb replacement on order from eBay. I didn’t have the problem of this radial “waggle” until I bought my first cheap Chinese fake GXP bottom bracket and noticed that when I road tested although the creak was gone the I had a kind of spongey waggle in the crank that was moving my outer chain ring in and out with a range of about 3 to 5 mm! This took me to Hambini, at least he admits to having autism so this could be a reason but I’m pretty ashamed as an Englishman that he was rude to you. You quite clearly have found a way around this. Perhaps I will need a better tool than the cheap ring spanner supplied that feels like a cross between plastic and metal. I do not have a torque wrench and have stripped my non drive side crank so I’m buying a new second hand crankset. Perhaps if I torque it up properly it will not waggle I hope but when I had it really tight last time the cranks didn’t turn freely. I am trying to extend the life of this oldish racer rather than give in and buy a new one. Anyhow lovely video and thanks for your expertise.
I went to a store and took my frame, I wanted to get the omnium cranks for my track bike.
I put in 3 different gxp bb the third one fit the other two didn’t... the threads were just off.
I then put the cranks on, one was to loose, the next was to tight; but the third one was just right lol.
Anyway my three bears story.
I’ve been using that set up for 6 years and it’s been fine, gone through 3 gxp bottom brackets but that’s to be expected.
If you find one that fits they are great, you just have to find a good one lol.
Nice!
what bottom bracket you're using on your omnium currently? I've been using the stock bb that comes with the crankset but it does not spin really well. I've read somewhere the stock bb is kinda trash so i've been looking for a replacement.
I expect my Shimano BB to last at least 5yrs of hard use, not even surprise if it last a decade.
So you throw the wave washer away, yet claim the BB is fine?
Yes
That bearing, without any spacers, was slacker than a wizards sleeve!
Yes it was, but once properly torqued between the spindle shoulder and the crank arm, it's tighter than spandex on a 350 pound woman!
Ha! Indeed indeed...
Very good i seen that video to you make alot of sense
Thanks! I appreciate your feedback!
I had problems with GXP : a lot of play on the ND side after around 2000 km. And I don't apply excessive torque on it (not a sprinter, very light rider that speen the leg).
Let's backpedal to the point when the crank was installed. How much torque was applied to the non drive side spindle bolt? It doesn't matter how much torque the legs are putting out if the crank is not installed correctly, (if the NDS bearing is not fully contacting the crank arm and the shoulder on the spindle, ie. Hambini syndrome) there will be play in the BB.
@@JoeyMesa There will also be play if the beveling of the shoulder that you mentioned earlier is not designed and fabbed to spec properly. And that is true no matter how much you gorilla the NDS crank spindle bolt. If it isn't fabbed correctly I don't care if you install it with 500nm's of torque, it will not work properly. Fact!
@@rcg9573 I've literally installed, maintained, and repaired thousands of GXP cranks on a wide variety of bicycles. I've even owned a few myself. I don't ever recall ever seeing one that was manufactured in a defective or out of tolerance manner enough to affect a successful installation. One thing I have seen is failure and damaged components from improper assembly.
The thing is, even if a product is designed perfectly, the tolerances are spot on and consistent, an inexperienced mechanic can still screw it up if they don't understand how the product works or the sequence of what part goes where during assembly, there's a good chance for failure. That's a true fact!
I find a lot of complaints about this crank stem from improper installation or maintenance.
I’ve had GXP on my last three Bikes and only had an issue with my current hardtail MTB and that’s because it got used as winter bike. Unfortunately I put some wear on my smaller spindle race... I did seem to fix it using a beer can as a shim since there was nothing to loose.
I have constant problem with GXP on my road bike (always a loosen ND side after 2000km). Do you have idea what sort of improper installation or maintenance could cause that ?
In addition to the other comment, make sure the dust cover is installed between the crank arm and the bearing. The spindle bolt needs to be TIGHT! Sram's torque spec is 48-54Nm, but I tighten them to the point where I can feel the crank arm bottoming the bearing out against the spindle shoulder.
@@JoeyMesa yes this is the design. The SRAM instructions tell you to keep greasing the splines and install/uninstalling until the splines get worn to the perfect fit.
With pedaling and repeated installation the splines can wear and get loose, so people then just tighten the cranks more....but you then need to move the bearings in the cups closer together to offset the spline wear.
There should be a spacer (crush tube) in between the 2 bearings preventing you moving that bearings though.
The road version SRAM force and some other BBS seem to be missing the crush tube, so measuring and spacing the cranks with washers might be the only solution if you have play in the bearings.
All the people that say they have premature bearing failures have too much side loading on the bearings. Using a bearing press to push the outer race of the BB bearings closer together will fix the issue.
In saying this, I have a giant xtc with factory fitted press fit gxp BB and x9 cranks. Zero free play and cranks still spin 4x when you wizz them. When setup they last forever, but if you wear the spindle splines there's a lot of mucking about to reset the bearing side load.
Is it compatible with shimano bottom bracket
Shimano crank spindles are 24mm on both sides. GXP spindles are 24mm on the drive side and 22mm on the non drive side. You could use a reducer on the non drive side with a Shimano crank though.
I see a lot of flack to Hambini, but in his defence, i think people are missing the point, the reason he doesn't like SRAM/ZIPP, is one, not the design, but the variance in their tolerances, he is not a bike wrench, he works in the aerospace industry and if you say it is made to these tolerances, it is. Whilst the bike industry states a poor tolerance, or doesn't follow their own specs. That is his argument, same with bike frames.
In essence, you can get a poor one or a good one, luck of the draw, that is his issue, apart from the false marketing.
So yes Joey, you get them to work, but should you have to with a 10k bike? That really is the question?
I've been a mechanic in the bicycle industry for a really long time, and I've worked alongside engineers in manufacturing. In my experience, I've seen way more bicycle-related issues from bikes due to poor assembly, maintenance, and adjustment than anything related to poor tolerances. There's more to keeping a bottom bracket creak free than tolerances and torque settings. This is my problem with Hambini. He focuses mainly on tolerances as an issue, then neglects fundamental assembly points when putting it back together. In his GXP video, he basically blames poor spindle tolerance as an issue when he never assembled the assembly correctly in the first place and designed a fix based on bad information.
10k custom-built bikes always require lots of special attention to get them dialed in right.
I have a bb86 frame with a token ninja bb. I have a Shimano crank but I bought a sram red for the weight.
I find the sram gxp an overcomplicated system when you have to measure with a caliper the size of the axle to decide how much spacers you need, due also to the manufacturer inconsistency (from crank to crank you can have mm of difference). To me Shimano has a simpler and better system.
Anyway, having a bb86 bb I need an adapter to fit the 22mm NDS part and I bought a token ninja kit + a ZTTO bb86 bottom bracket (and the adapter).
After an evening of measurements I decided to go with a 2.5mm spacer in the DS to fill the gap between the crank and the bearing (if the axle enter completely in the DS, the bearing doesn't work on its axle "bed") ditching the wavy, adapter inside the NDS bearing and that's all. It should work ok with no gaps and no rocking movements.
This is only theory at the moment.
Entering the axle completely in the DS I will get too much axle exiting the NDS and I should use two 1mm spacers (one per side) and a shorter adapter...
In my opinion too much thinking for a simple crankset :D I save it just for the look and the weight
You lost me at Token ninja BB...
funny how that GXP came with 24mm spindle diameter on drive side, and stepped down to 22mm on non-drive side.
And, having none off-the-shelf bearing for the non-drive side with ID of 22mm, the bearing that came with this, has a sleeve of 1mm thick, so they 'fit' together.
Not sure if you call this engineering or SRAMineering.
I like how if someone can't figure out how something works it's automatically "poor engineering".
Joey Mesa we certainly understand that the 24/22 taper will help slotting spindle from one BB end through to the other. However one more part means more tolerance to be considered.
What I'm hearing is you don't fully understand the concept of the GXP system. Just like Hambini didn't understand and created a shim to "correct the tolerances" , when that tolerance isn't even crucial. I'll say it again, the 22mm bearing id doesn't matter. When installed correctly, the NDS crank arm and concave spindle shoulder are the only crucial contact points against the bearing.
Joey Mesa thank you. I’m all ears.
Wow
The frequent exchange of thoughts had attracted me to finish watching the whole video.
And it’s still the same old gxp that i knew, and I’ll keep my opinion.
Now you mentioned hambini the other guy, well I’m not a fan of his vulgar words, but I’m with him, for far too many things happening in bearing applications within cycling industry is making itself a laughing stock. Well it won’t, because they are playing blame game: no it’s the frame, no it’s manufacturing, no it’s the installation etc.(psst..it can never be the design that’s flawed;)
Now back to the gxp.
1. It is still using wedge design for a ‘nice fit’, from the way you hand-tighten crank bolt you know that
2. and you didn’t tighten it to torque specification, don’t try, because it doesn’t work all the time, as staying within torque spec will not guarantee a ‘nice fit’ for NDS bearing’s inner race in longer term of use.
3. Wedge fit has been used for ages on square tapered solid BB spindle or even older. It’s the best design for industrial crank arm that has no dependency to other feature or functionality such as bearings’ optimum fit, or when one is flexible with its final axial position (in cycling industry the fancy name is Q factor isn’t it?)
4. For spindles other than solid ones, such as those with large bored out hole, the physics behind is a complex mathematics function/model, where every unit of tightening torque translates to extremely high axial-tensile load on the spindle forcing a reduction of its diameter, while wedging on, at the same time clamping onto bearing’s inner race,
5. 11:42 That’s why a ‘trial-and-error’ methodology is required, and it’s result defer from one person to another
6. 2:03 Pls don’t tell us it’s a 22mm bearing, there’s no 22mm bearing off the shelf with the same outer diameter as DS bearing, it’s a 24mm bearing fitted with a sleeve
7. Wavey washer is optional for cases where rubbing with bearing’s outer race could happen.
8. Lastly, you have hinted, shimano is good, sram is not bad. But if it takes an expert with tenth of years experience to install ‘properly’, there’s reason why it’s not the top choice.
Hey Joey... I just posted my video response on the GXP topic.
Le sigh. Too much talking and (incorrect) speculation-no wrenches or installation process???
Have you ever actually installed a GXP crank?
I like the gxp system because you cant overtight it since the 22 mm bearing takes all axialload . ( the 24mm bearing only takes the radial load and are floating ) . Rather smart.
You are correct!!!
... can't overtighten* it (...) takes all* axial* load.
Sharing my experience, it is bad, it flexes, it creaks and the chain drops due to the wave washer tiny compliance (and spider flex). After 16 months on a Quarq DZero pm I can already see the bearings marks on the axle as predicted by engineering analyses ;) (Please don't say you installed something wrong, we are all adults here.)
Thanks for the video Joey Mesa.
Having ridden a host of different BB configs over the years and having had very little problems with most of 'em I still agree with Hambini's criticism of the GXP design. That is, the non-drive side bearing takes of all the lateral load required to secure the crankset. Greater friction and accelerated bearing wear especially when typically shoddy QA/QC protocols are factored in, eg, misalignment of the bearing surfaces in the BB shell, are the results.
That doesn't mean I'm going to ditch my SRAM Apex crankset as it's on a S&S coupled bike and the convenience of completely removing the crankset with one 8mm allen wrench supersedes design deficiencies.
Mediocre designs can be functionally adequate but they should never be mistaken for good or optimal designs. This is the point I believe Hambini was making and having no problems with our GXP's doesn't negate that.
Thanks for your feedback Luke!
I, like yourself, have owned and ridden pretty much every type of BB/crank set up out there. My day job for the last 37 years has been in the bicycle industry mainly as a mechanic. There's not a system out there that's perfect, but from my experience long term durability wise, the GXP system is one of the better ones. The only real issues I've seen with a few GXP cranks is the spindle separating from the drive side crank arm or the aluminum pedal boss separating from the carbon on carbon models.
I honestly haven't seen bearings on a GXP crank wearing faster than Shimano bearings. I realize the non-drive side bearing takes all the axial load, but the radial load on the bearings is much higher, especially on the drive side, witch on the GXP bearing is all it has to take. Truth be told, in the last 4 years, I've seen more warranty issues with Dura Ace and Ultegra cranks (splitting in half) than GXP cranks. I still think the Shimano hollow tech system is great, but it's not perfect.
My biggest issue with Hambini is his mechanical ability is not in line with his engineering ability. Most of his analysis is just calling people names and offering no constructive advice. His fix to the perceived problem was a shim to allow a standard 24mm id bearing to be used on the "out of spec" spindle. The only issue I saw was his inability to fully tighten and engage the crank arm onto the spindle splines.
All GXP non-drive spindles are well under sized if you put the bearing loosely on the spindle and wiggle it side to side, it seems like a really loose fit. The spindle shoulder is beveled and centers the bearing when the crank arm is secured against it. Hambini just doesn't understand that part.
All in all, I think Sram's consistency in quality control and tolerances is decent. There's way more variability in bike manufacturers than Sram's components.
6:30 - I think, you know the answer from Shibas video: the radial gap is still there (because of the wrong choice of bearing size), you just cannot feel with your hands, because it is tightened. But be sure, your body weight will be enought.
The other design failure - as you mentioned in a comment -: the NDS bearing gets all of the axial loads, while DS gets radial only. That is the same what Hambini sad.
Again, I don't think you fully understand the concept of how the GXP system works. There is a bevel on the step where the spindle diameter increases. Once tightened CORRECTLY, there is no movement between the spindle and bearing. If you do not torque the NDS crank arm on sufficiently, there will be play between the two and the bearings will fail. That's not a design fail, that would be the installer's failure (Hambini). I don't know if you can call the radial only load on the drive side a design flaw, at least I haven't seen proportionately more GXP drive side bearing failures than Shimano. The drive side bearing take more radial load anyway due to the counter forces of the chainrings.
I generally tend to judge a product by it's long term durability though.
@@JoeyMesa You misunderstood me.
I mean the gap between the bearing AND the spindle (... and NOT the axial play of the bearing ON the spindle), what is caused by the wrong choice of the bearing size. That is one part of the bad design: NDS Spindle size (as Shiba measured): 21,93 mm, NDS bearing bore size: 22,2 mm.
~0,3 mm play is way more, what it should be.
About forces again: axial forces are additional (Is this the correct word?) in this case, but they are there. The DS bearing cannot deal with them, because it is not fixed on the spindle (axle).
The NDS bearing hold them all, because it is fixed. That is reason, why the NDS bearing always damages much more earlier, then the DS bearing.
At Shimano's design both of the bearings are fixed, so they share to keep up with additional axial forces, that's the reason why both last longer.
...and sorry for my english.
My own experience with 2019 Trek
Madone SLR 9 Etap: Misery from the 1st day.
Creaked on the 1st ride. Poor spin test.
Hambini's assertion that GXP has a problem on the NDS because the inner race is locked to the spindle certainly seems valid.
All they trouble I've had is with the NDS bearing. Trek's fault - frame alignment or interence fit tolerance? Sram's fault - a S load pattern on NDS bearing?
Either way, I bought a very expensive bike that has been nothing but s@#t. (sorry, there's
no other way to describe).
My next bike will not be Trek and will have Sram groupset.
Thanks for your post. Thumbs up.
Thanks for your feedback Steve!
Did you purchase the bike new? Who assembled the crank/BB?
Hambini claimed the main issue with GXP was poor tolerance fit between the NDS bearing and the machined portion of the spindle. Any halfway decent mechanic could see Hambini didn't fully torque the crank arm. You need to be able to feel the crank arm stop as it locks the bearing between the shoulder on the spindle and the crank arm. Failure to do this will result in issues.
Joey Mesa
Hi Joey,
Brand new.... ordered custom as a Project One. Opted for Ceramic Speed bearing.
The dealer and I assembled out of the box. The Waterloo factory assembled bottom bracket, drive train and brakes.
I heard creak on the first ride. Immediately spoke to dealer and Trek technical help desk.
My dealer sells mostly beach cruisers. He sprayed WD40 all
over the place. Wouldn't it be nice if just spaying WD40 fixed complex problems?
Trek is interested in moving product, not standing behind their
bike. Trek's lip service: could be pedals, could be gears, could be sun spots.
And, it is well understood that a bearing moving around in BB shell will destroy the frame. That is what happened.
Trek never offered no way to remediate while it could have been easily taken care of.
A shame because it is otherwise a really nice bike.
Best regards, stevesocal40
You lost me at beach cruiser and WD40 all over the place.
Joey Mesa
:) :) :) If you gotta' pulse, you can be Trek dealer.
He IS a nice guy, though. I still buy stuff from him.
Steve Flor sounds like an incompetent mechanic set it up. Get a wheels thread together in infinite bb and your creak will be solved.
Except it’s not designed for installation like that. The stepped crank shaft should clamp the NDS bearing, removing all lateral play. The wave washer on the other side is only there (if required) to hold the dust cover in place. It’s not designed for use with angular contact bearings. It seems wrong to evaluate the performance, whilst also ignoring the manufacturers installation instructions.
I think that's pretty much what I said? I usually just ditch the wavy washer. I had a Wheels MFG PF30 to GXP conversion BB with angular contact bearings. I sold the bike it was on eventually after over 15,000 miles on it. Still spun smooth as butter!
Joey Mesa i don’t understand why in the second half of the video you show packing out the DS? Wheels manufacturing sell spacers, as well as very stiff wave washers, only because their BB has angular contact bearings that are not strictly compatible with the Truvativ GXP system. It’s easier to use a BB that has radial contact bearings (e.g. SRAM/Hope) which do not require preload. The NDS bearing should take all the lateral load and there should not be any creaking. The thin wave washer is only required for the pressfit BB variant and only to lightly hold the dust seal in place. I have no creaking from my SRAM GXP cranksets and they spin just fine.
@@likemarksee Yes, overall you're correct. My theory is that if the DS void was filled, not packed, with spacers, it could even the lateral load on the NDS bearing. Probably doesn't affect anything, but the goal was to get the crank spinning as free as possible.
I don't like wave washers because they can put too much load on the dust cap/DS bearing in spots causing drag. I like using shims to lightly hold the dust cap in place if needed. If there is a sizable gap, some guys like to use an o-ring, which would work well in that situation. I think the main issue with GXP is many folks just don't understand how it works. The drive side gets too much spacers+wavy washer and causes a side load issue with the DS bearing, or in the case of the Hambini video, the NDS crank arm is not properly torqued. If the NDS bearing is not locked tight between the spindle shoulder and the crank, there will be issues.
I've also seen lots of cranks installed with extra spacers on the NDS. If the NDS crank arm doesn't have enough purchase on the spindle, it will eventually work loose. This would be the case of Hambini's fix, as he created a 2-piece spacer to fill the void of his inability to fully tighten the crank arm. At least that's what it looked like to me, he never gave any measurement specifications.
As far as angular contact bearings, it seems the NDS side would benefit as it sees radial and lateral loads. I'm not sure what Wheels MFG uses on their angular contact PF30 to GXP outboard BB's, but for me that thing was bulletproof. I never touched it for 2 years and it never creaked compared to my BB30/PF30 that needed maintenance frequently or it would creak.
Anyway, thanks for your feedback, I really appreciate it!
Joey Mesa i also switched to SRAM GXP after suffering with BB30. Far from the worst system in the world, i think it’s pretty good. I also thought it strange that the crankset Hambini fixed would not tighten in the first place.
@@JoeyMesa All true, but I have had quite a few times a scenario in which the properly tightened crank bolt came undone during the ride. Otherwise, a smooth and problem free operation for 10k miles so far. That with a Hope press-fit bb.
according to SRAMs website a gap between the crank and driveside bearing is normal...
Yeah, generally it's totally fine unless you're running a BB90 bottom bracket on a Trek. If there's a gap on the drive side, the non drive side bearing can migrate out of the frame snd cause damage to the carbon fiber.
Joey Mesa thanks for the reply!
You calling out Hambini? Lol.
Maybe I disagree with his assessment of GXP, so yeah, I guess so...
@@JoeyMesa Ha yeah he's something else.
mmooppaarr6699 hambini's an actual engineer LOL
'a little bit of play'
bearing: *turns 1 degree in each direction when he wiggles it*
@@JoeyMesa So I'm installing a Sram Force now, GPX it is.
Hambini says all Sram products suck. And his channel is engineering entertainment.
Decent you call it. Be like apple this sram crank is like android. I don’t have time to fix something I purchase. I want plug and play. Thanks for all the insight on it . Great job.
sram is moving to dub, which tells you something about gxp
Yes, I think the Dub system is better for modern carbon fiber frames, but on the flip side, I don't think GXP is awful.
Tells you nothing!
It tells only that they want just one standard with oversized axle that can be fit on every frame
Jura Stanić i do not have dub, but anyone moving to oversize, is to move away from steel and use aluminium for almost everything.
DUB isn't any better, it has its own issues. DUB was created with the sole purpose to prevent compatibility with other firm's products, not sound engineering principles or any advancement of BB/crankset design. Hence the intentional and random 28.99 mm spindle diameter choice. There is no logical reason for that spindle to be designed with a goofy random 28.99mm diameter other than an intentional attempt to block other firms products from the market, and anyone with a 3 digit IQ knows it. :-) I'll never run that shit on any frame of mine just on the principle of it.
Robert Gardner Agree. Whenever i see crank with spindle mounting on DS, i always imagine an ‘ikea-designer wannabe’ engineer trying to flat-pack the cranksets packaging saving a few pennies for his company.
Rotor
i think that you have to remember that the weakness of Hambini's reviews are that he is sent components and frames that are all screwed up to begin with. So his reviews are totally biased to the junk side because the parts that he is supplied with are junk. My view is that he is really reviewing that outer limits of the quality control. One important thing to think of is that he actually says what they are supposed to be such as maximum bearing clearance fits. For instance, Trek BB90 bearings have a 0.1 mm interference fit. The quality control on the BB90 is not very good and hence with not a lot of age, they start hammering the bearing loose and it starts making a lot of noise. Trek also supplies oversize bearings but these things are 0.8 mm interference fit which is far too large and would beat the bearings to death rapidly and replacing these oversize bearings would ream the press fit out and soon make it unusable. In response to this problem Trek has apparently made a special boring tool that will open these BB holes up to the required 0.1 mm fit. The weakness of this is that if you knock these loose you're SOL. So the 2021 Trek top end frames have T47 thread-in bearings. If you manage to screw this up you simply replace it with a new one. The basis of a lot of problems is that there are FAR too many riders that weight over 220 lbs riding these parts that are actually designed for 190 lb riders max. One of the local riders happily bought his Trek frame new from a certified dealer and has broken four of them since he weights over 240. The Trek lifetime warranty really has paid for itself over and over. Were you to send one of these frames to Hambini after he's broken them up, he would really roast them and really it is not Trek's fault at all. So the view of a professional mechanic and an engineer that is trying to correct these problems makes for a lot of "French" if you know what I mean.
Hambini is not an engineer.
@@jonathanchung7209 - Hambini has a college degree in mechanical engineering and has worked in the aerospace industry in the design of jet engines. Can you explain to me why you decided that he isn't an engineer? That is a serious lie which leads me to believe that you have something to do with SRAM. That is also legally libelous so perhaps I should simply turn this over to Hambini.
@@tomkunich9401 lol, what a hambone sycophant
i've owned two. They are the worst.
Why? What specific issue did you have?
@@JoeyMesa Incessant creaking, premature bearing wear. Shimano has had no such issues, even with press fit versions.
@@bubbastard I haven't seen how your cranks were set up, so I can't speculate. I've owned several Shimano hollow tech II and Sram GXP cranksets, plus I've had the opportunity to work on several of each type weekly, consistently, for the last 15 years since they've existed. From my experience, from durability and problematic standpoints, when installed correctly, they're really about the same.
I will say Shimano cranks are much easier to install correctly though, at least by the general public. The most common issues I've seen with GXP cranks are extra spaces on the non-drive side causing the crank arm to not have full purchase on the spindle, which will cause creaking and eventually a loose-fitting crank arm, and/or too many spacers on the drive side, which will sideload the drive side bearing and cause premature wear as well as poor bearing spin. Not enough spacers will cause excessive stress on the non-drive side as well.
The play on the non-drive side bearings is unacceptable. To expect us to keep the outer bolt tightened to 54nm all the time is not realistic. That's the only way to keep the bearings from being destroyed because of the space between the left side of the drive shaft and the bearings. The shimano system has zero play between the drive shaft and the bearings, which makes for a cranks with zero play if you delicately preload the bearings. I "Upgraded" to a GXP compatible crankset that came with a perfectly machined shim for shimano compatible bottom brackets. I tried it with an Sram GXP bottom bracket and it just has too much play unless its tightened down. Meaning the bearing is only held in place from the sides and not supported from the bottom of the race. Looks like the only way I can get this system to work is to go entirely with Chinese GXP copied parts and use exactly the BB spacers you need to get a 73mm shell between the aluminum cups, that seems to be the only fix.
It works fine for me for several years.
Me too!
I ran one of these things a few years back. Very worst crankset I have ever owned, hands down. The thing would creak just by looking at it, well not really, but it was almost that bad. Bearing life was also a joke. Bearings had to be replaced towards the end of season 1. Ended up ebaying it and recovering very little of my loss. This is simply a very poor design, and what makes the design exceptionally poor is that even if you gorilla the non drive side crank arm down to center the bearing on the beveled shoulder as you claim if that beveling is out of tolerance at all you will not center the bearing properly. Mechanical fact! This is a perfect example of a design flaw that will almost always play itself out in the fabrication phase of the product (unless you have both very, very tight tolerances and the ability to fab to those tight tolerances consistently - which SRAM does not !) because it is a design with very little "tolerance" for fabrication error or installation error in order to work correctly. Given SRAM's miserable history regarding their actual fabrication tolerances (they are well known in the industry to be a joke compared to Campy and Shimano) I will never buy one of their cranks again. I have run several different generations of both Shimano and Campagnolo cranks on road, cross, gravel and MTB's, and never once had the issue I had with that SRAM GXP junk. In addition, the very moment I removed that SRAM junk and replaced it with a basic Ultegra 6000 series crankset, guess what, creaking issues immediately disappeared and the bearings on those cranks are still going strong after multiple seasons. So it was not a frameset issue.
Yeah, you should probably stick with Shimano, it's really easy to understand the assembly process.
I have all time side Play...
a) For problem which Hambini had at 5:40 he have just to go fitness and train muscles to apply enogh force. OR. b) Engineering approach. As he mentioned that force to apply for torque is increased "exponentially" then he may just take "exponentially" longer wrench . b) variant is preffered as it gifts more FIntness 😁
I think you're on to something!
I’ve got SRAM Force 1X11 Love it I know hanbini did criticise sram but plenty of my friends have Sram with no problems my only complaint is it so expensive.
Yeah, I've got a similar 1x Force/Rival set up on my commuter bike and I'm impressed with it's durability. Thanks for taking the time to leave feedback, I really appreciate it!
@@JoeyMesa I have a quarq dzero for 5 months. I can see the marks in the spindle already. Exactly as Hambini says. Normal humans might no feel the difference, but it's a design fact what he stated. :/ (just to illuminate the topic, I had not less than 6 lever sets replaced in warranty with unstoppable dot 5.1 fluid leakage)
@@ebigarella 99% of issues with GXP systems are from incorrect assembly, and not poor workmanship as Hambini states.
At least that's my opinion from working on thousands of these cracks and seeing any and all possible issues. Hambini may be an awesome engineer, but he's not a very in tune mechanic.
Brake wise, I've seen more warranty issues with Shimano levers and calipers lately than Sram, but like most Shimano vs Sram components, Shimano stuff is easier to work on.
I believe generally, poor workmanship gets the blame when the real issue is poor mechanical and problem-solving ability.
Me neither, I bought my Sram Omniums with a GXP bb in 2017 which I did not attempt to clean in 5 years. I can honestly claim that I got no issues and still using it on my beater.
Thanks! I appreciate you taking the time to leave feedback!!!
GXP design is very bad from bearing and axle construction point of view, it looks like good and simple design, but looking at axxle you can clearly see worn out axle from drive side. Also people are buying to just to have option of different bottom bracket fixing with voices issues. Like myself. Nothing else : )
The fact that the non drive bearing is non preloaded is exactly why it is a poor design!
Please explain why the bearing needs to be preloaded and why that's an issue if the non drive side is fixed? I've installed and serviced thousands of these without anything different than the issues that you'd see in any other BB design.
First!
If you ain't first you're last!
Yes. It's the worst crankset. Overcomplicated, asymmetric with no reason
GXP WORK GREAT. bb30=bad apples
Yes, that's pretty much been my experience as well!
Yes it is the worst - such a piece of shit. Always loosening, fucked bearings within months.
Sram should be ashamed of themselves
So please explain to me how since this cranksets inception, I've installed and serviced literally thousands with very little long term issue? I have seen quite a few that were installed incorrectly in ways which can cause the non drive side crank arm to work loose and or damage the bearings, but that's not really an issue with the crank system.
Complete crap. End of
End of.......What? Your ability to learn?
@@JoeyMesa Oh i learnt from buying a bike with this crank fitted that proceeded to mangle after a few uses. I learnt to replace it with decent parts. Parts that don't encounter the same problem from endless users which is well documented. You should learn how to identify a flawed product lol
@@danjay2767 I hadn't really heard of any widespread problems with the GXP design. I saw Hambinis video where he diagnoses a problem with the step-down section of the spindle but incorrectly installs the crank arm sufficiently. That's not a defect or flaw in the product, that's improper assembly, which will cause the bearing to fail. That's also what compelled me to make this video in the first place.
I did a google search on any recalls or any documented flawed product tests of GXP BB's, but could only find a few isolated instances on forums and such.
Working on bicycles has been my day job for 37 years. I've installed, serviced, and troubleshot thousands of GXP BB/crank setups, as well as every other type, and have never seen any problems due to flaws in the design of , manufacturing defects. What I've personally witnessed is an endless number of bikes that have obviously been ridden into the ground with excessively worn drivetrain parts, but the original GXP BB was still working fine.
The issues I've seen are from very poor frame BB shell tolerances and/or improper assembly.
2 seconds in "I dont know" no need to go any further:)
As in "I don't know why people can't understand how this crank works".
When installed correctly, the system works. That I know from experience not theory.