Virago Trouble Shooting - Only Running on One Cylinder...Sometimes it's not the Carbs, LOL !
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- čas přidán 30. 04. 2022
- Diagnosing only running on one cylinder for the Bobber. Sometimes a fouled plug will act like a clogged idle circuit since it doesn't want to fire at idle, but when the rpms are increased, it will fire since the voltage is higher with higher rpms. Also, some tips on reading a Cylinders Compression and how the gage can be misleading.
- Auta a dopravní prostředky
when it comes to viragos you are the man.I like the way you explain each situation and you speak to us not down to us.Keep up the good work and please keep making video.Rick T
Thanks man ! Since there’s not much info on the details of how to keep these cool old bikes running, I always try to explain as much as possible so it makes sense what I’m doing (probably too much detail in some cases and folks get bored with the video sometimes, lol). Usually I’ll make a video when something new comes up…which does happen periodically now that I have 4 of them 🤣🤣. Thanks again and all the best ! Steve
@@StevesDIYs seriously your virago content is unmatched, I’ve got a 94 xv535 which is slightly different than this one but your checks have got me running again and I can keep building/riding
@@joshuahedden8407 thanks man and glad the videos have helped some 👍. I recently got an ‘87 535 as a non runner and I’m hoping to gather up enough of the missing and bad parts to get it on the road. I’ve never had a 535 so it will be interesting to see how these go together for sure. Thanks again and all the best ! Steve
after watching your vid on carb adjustment I finally have a running, riding bike and I owe it all to your wisdom and smooth demeanour.Thank you Steve ,you are a virago god!!!!
Thanks man and glad the videos help some 👍👍👍. I’ve always enjoyed working on my bikes and cars so I figured other folks might find the DIYs interesting. Nothing beats being able to see something being done vs. trying to decipher text in a manual I always say. Glad to hear you got yours running and all the best !
@@StevesDIYs moja yamaha virago xv 750se kad skinem jedan kabal ugasi se nece da radi na jednom celinderu što je problem. Hvala
Ya know, before this year, I have never worked on a bike. Since watching your videos i have learned the easy way to remove and repair my carbs,and with great success.and now my bike started running on one cylinder and that video saved my but again.as it was a fouled plug.not to mention having to change my stator which was poor.i don't know what else could possibly happen to this bike ,but if something does I' sure hope that you have made a video for that. Thanks again for helping me repair my bike
Thanks man and glad the videos have helped 👍. These are fun bikes to work on (to me anyway, lol !) so as things come up, I’ll usually make a video just so folks can see. My plan is it one day pass these old bikes on to my boys so with all of the videos, there shouldn’t be any excuses for not keeping them running for another generation, lol. Thanks again and all the best !
great video steve! your videos have helped me get my virago project running great!
Thanks man and glad the videos have helped some 👍. These bikes can sure get grumpy sometimes, but fortunately in most cases it’s just something simple. All the best ! Steve
Great info. Didn't know about the resistor in the plug wire. I'ld clean up the old plug and carry it as a spare in case of an issue on the road.
Thanks man ! Yep, I usually clean them a little and then throw them into the stock bike and let it get them nice and crispy again…then put the one that was in the stock bike in the side bag 👍. I do agree that It never hurts to have an extra riding along with you just in case for sure 👍👍👍. All the best ! Steve
Omg I had that probs to, I put 2 new spark plugs n she fine again. Now I have to get a new cdi unit, aka brain box. Good video content as always.😄
Thanks man ! Yep, I think my jets are a bit too big having to compensate for the additional air and more open exhaust as the bobber tends to always run the plugs black. The Iridiums seem to be more resistant to fouling, but eventually the carbon builds up and they won’t spark. Probably doesn’t help that I start the bikes in the winter every couple of weeks to keep the carbs clean…doing that after several winters probably fouls them bad enough that they won’t clean up on their own the next spring. Thanks again and all the best !
Hi There Steve, I greatly appreciate another very well put together informational video. You do such a great job of explaining the situation. Your bike sounded so much better after you changed the spark plug. What brand motorcycle helmet do you have in this video ? Notice that it is a modular, or flip up design. Thank you very much.
Thanks man 👍. Yep, it was much happier with a new plug for sure…nice that it was just that so I still got to ride it yesterday 👍👍. For the helmet I have, it is one from Amazon I got so I don’t have to take my glasses off each time I put the helmet on since the front opens up. Here’s a link to a picture of it I put out on my Steve’s DIYs Facebook page (CZcams doesn’t allow pictures in the comments, but does allow links): facebook.com/109400450606405/posts/559169452296167/ . Thanks again and all the best ! Steve
I disconnect the rev-counters on mine, they apparently take the spark-reading off the rear-cyl which robs some spark. It does run better. I also 'index' the plugs,periodically dismantle and clean the caps, plus run iridiums . Everything makes them run a little better. There were large HP differences on the gen 1's at least, from new. Also check the size of breather-holes in the tank-caps, I've seen this make a difference on them also...so many things !...but so great when everything comes together . Dave NZ
👍. Yep, there are so many little things that add up to make a big difference for sure. The carbs are fussy I’ll admit, but there are many other things that act just like dirty carbs on these that throw people off. I’ve never really thought about the tach pulling some of the signal off...that’s a good catch 👍. All the best ! Steve
Great content!
Thanks ! Yep, Sometimes it’s an easy issue to fix on these fortunately, lol. All the best ! Steve
Hey Steve. Another good video. I am learning that the older Virago also have coil issues. I recently watched a video where the guy had a good explanation on the coil and lead combination that the Virago uses. Seems the wire breaks down then you end up with a weak spark. May be why your front plug is fouling. I also read where many owners have issues with fouling plugs. Here is the title of the youtube video and the guy's name is Ken. "Yamaha Virago Ignition Coil Replacement" . I think I am going to order the coils and caps for the future. Any projects for the 1100 in the near future? Looking forward to another of your informative videos. Tom
Hey man ! I just watched his video…he does do a good job of explaining why they go bad and also explains how the resistance works 👍. Yep, seems like these old coils just break down after a while (I’ve got several in the attic that are just outside of the acceptable range). Fortunately the old 1st Gen ones have a removable wire from the coil and use copper so the wires can be swapped out for thicker copper to reduce the overall resistance. It looks like for the 2nd Gens they are molded together so this wouldn’t be possible.
For the 2nd Gen, the next big step is to make it pretty again with a new paint job which I should start in after the spring time bugs die off here in Tennessee 👍
When my 1982 920 sits for a while and I loose a cylinder, the problem has been a stuck float. When I drain the bowel it fixes the problem. Thanks for the resistor explanation. The NGK BP7 ES is very difficult to find.
Thanks man ! Yep, I was hoping I wasn’t going to have to fiddle with the carbs for sure. I try to run ethanol free in the bikes most times, but definitely use it for the last tank fill up at the end of riding season. It’s always seemed to do better come spring time on ethanol free (maybe just in my head though, lol !). After the plug change, it was back to it’s old self again and cruised along all happy again 👍. Yep, I’ve never been able to find the Iridiums without the resistor so removing the resistor in the plug boot works really good 👍. All the best ! Steve
What a fantastic video.
Thanks man and hope the video helped a bit with how to diagnose these 👍. All the best ! Steve
Sounds exactly like mine did when the carb-to-jug intake boot for my rear cylinder was dried out and cracked. The vacuum leak was bad, but opening full throttle bat it cough to life and backfire a lot as it cleared out the unburnt gas.
👍. Yep, a lot of times it’s something with the air fuel on the carbs or like you said, an air leak from somewhere. Fortunately for mine it was just the plug.
Man, this is the same issue I'm having. I've decided to rebuild my carbs as well.
Yep, these can be grumpy on the plugs and carbs for sure. A good carb refresh never hurts anything I’ve found 👍. All the best ! Steve
Hi Steve.I think i have a problem that not even you have come across.after a very long sleep i purchased this 82 750 with very low mileage.I had to replace the starter button before i could get it to turn over but after changing it success,it turned over.So after a long line up of repairs it was finally time to start it up and click click,no turn over at all.I tried two different relays and nothing.Checked all of the relay switches twice with two different ones and still nothing.I checked to see if my starter was ok and it turned over fine after hot wiring itwhen i checked the solonoid it was letting power through when the start button was depressed so im pretty sure thats not the problem.So here I am pulling my hair out trying to figure out why it turned over before and now nothing.Any help would be appreciated kind sir .Your frustrated follower Rick Taylor
Steve, great video; I am curious, however. What would happen if one removed the resistor then ran a non resistor plug? Would the plug wear out faster from increased voltage or will it make more power at high revs etc?
Thanks 👍. I believe the general use of resistors were originally added to plugs (or the wires) to help suppress the electrical noise as the high voltage ran down to spark the plug…older cars would have a feedback noise through the radio for example from the unsuppressed voltage traveling through the wires. For our bikes, that might mess with the TCI, tach, or cycom (on the 920’s), but I don’t know if it would hurt anything. I’m guessing that the resistor kind of takes the turbulence out of the voltage a bit so it hits the electrode smoother and makes a good clean spark. Without the resistors, there might be a tendency to fire an infinitely small amount quicker, but might not be as consistent with varying motor temp or rpms. I don’t think it would hurt anything to try it though to see if there’s a difference.
I switched out to the Iridium tip plugs a few years ago…mainly because this type is in my Nissan Frontier and I noticed how clean the small part of the tip stays even though the arm of the electrode gets carbon on it. I figured that intensifying the spark at the Iridium tip and it being the consistent place that it sparks would help keep the plug from fouling. So far this has been the case as I used to change plugs most every year on the bikes, but now, I go a couple of years before I have to pull them and torch them, lol. Hope this helps a bit and all the best ! Steve
Hi Steve, you’ve been helping me with my XV920 project which I just finished which won’t start and idle without throttle. I continued watching your videos and came across this one. I assumed maybe it’s the Autolite AP63 spark plugs in my XV that’s causing the problem and purchased the factory recommended NGKBP7ES. Unfortunately, the spark plug wire caps don’t fit over the NGK BP7ES spark plug heads for me to attempt to start it. Should I try to pry the spark plug wire caps open wider? Any tips would be appreciated.
Hey man ! Do the NGKs you got have the caps on them that unscrew from the threaded stud? If they do, the threaded end should be the same (or very similar) to the other plugs. Reason I’m wondering is that I got a set of the NGKs BP7ES one time that the top of the plug was not the removable type so they couldn’t be used on my bike. They must have been for a car or maybe an outboard motor or something.
Where did you get the air cleaners?...they look very clean and I like the look
Thanks man ! they are actually from a VW bug, lol. The part number is AC129741...got them off eBay. To connect them to the carbs I used 4 ply Silicone reducer elbows that were 50mm ID on one end and 60mm ID on the other...just had to cut the elbows down a bit so the air cleaners didn’t stick out as far from the bike 👍
Peace brother
Thanks man and all the best !
I have Mikuni's on my 82 Virago, and cylinder 1 wouldn't fire. Very temperamental. Slapped these NGK Iridium's on and now I'm getting both cylinders. I am getting a bit of backfire when throttling off, however.
👍. Yep, the iridiums have done really good for me on the bikes over the years. Popping on decel is pretty common I’ve found if the carbs or boots are dirty inside or the heads have some carbon buildup on the valves, as fuel collects up in liquid form then gets sucked in once the butterflies close and the intake air is restricted. Sticky slides or restricted air to the air inlets to the diaphragms can do this as well. The last one I’ve encountered for popping is if the compression is low on a cylinder as some of the fuel doesn’t get burnt good and then detonates as the motor is decelerating…that one is an easy one to check for to rule out.
Still the biggest problen of my virago build we were able to move the issue from rear to front and have narrowed it down to the pick ups being faulty so waiting on that to get done
👍. Yep, electrical issues are more difficult to diagnose than mechanical ones for me since I can’t see the electrons moving inside the wires to know which part is bad (I’m a mechanical engineer, lol !). The multi-meter and strobe light become my best friends when I have electrical issues. Hopefully you will have it up and running soon 👍. All the best ! Steve
This may sound stupid but my rear cyllinder gets hot but the front cyllinder stays cold at idle. When I put my hand at the end of the exaust of the front cyllinder I can feel pressure. So i’m not really sure if the motor is running on both cyllinders now. Sound like it but i’m not sure.
Hey man ! It could be that it’s only hitting on one cyl at idle then picks up once it is revved up if the idle mix needle is out of adjustment or the idle circuit is clogged up. The transition from idling to throttle up would have a pretty noticeable lag though I would imagine. If you still have a stock intake setup, you can remove the rubber elbow that connects up to the carb and put your hand over the end of the carb to block the air and it will lift the slide up. This will make it pull fuel from the main circuit (put your hand over the carb intake then pull your hand away). If the cylinder fires up doing this, you might have the mix needle in too far or a dirty circuit. You can also open between your fingers and regulate the air flow (balancing the air/fuel mix basically) to get it to fire until you can adjust the mix needle (if that ended up being the problem). Maybe give that a try to see if it makes any difference 👍.
hi Steve i have a problem with my bike.I have a backfire through the intake on the rear cyl .Any ideas
Hey man, from what I’ve seen, if one cylinder is backfiring pretty consistently it has been from the carbs not being sync’d. The more “In tune” carb will lead the other one and make it still rotate even though it skips a firing stroke. Then the next stroke that cylinder will fire a fraction early since it has like twice the fuel and it fires back into the carb. For the 1st Gens, there’s a video on the channel for the basics of doing a bench sync as well as a final sync on the bike and I actually just did a how to sync the carbs video for my 2nd Gen the other day that I posted. The other thing it might be is a dirty plug as well. The different videos are in playlists on the channel for the different bike generations as well. Hope this helps and all the best !
Love the videos bud, would you happen to have a spare throttle bracket that connects to the carb?
Thanks man 👍. Are you looking for the bracket that the cable end attaches to the butterfly shaft or the upper one that the outer jacket ferrule sits in (bolts on to the diaphragm cover on top of the carb)? I don’t have a spare upper one, but do have the lower one that connects to the butterfly shaft. It’s chrome is all pitted though so you probably wouldn’t want it though.
Yeah the small one that uses the diaphragm bolt on the top
Mine did the same thing, wound up being one of the vacuum hoses came loose from the carbs/petcock.
👍. I’ve had that happen as well when the cylinder pops back into the carb 👍. That’s a tough one as well to find unless you can hear the extra air sucking in the hole were the hose was connected.
Hi mate. Could you please advise?
I have swapped the front cylinder head ( not the barrel) on my 535. I can't seem to time it up. It's a half tooth out either way I try it.
Front cylinder is staying cold. Backfiring and spitting fuel out of the exhaust.
It's a single carb conversion running a Mikuni VM38. (This ran the bike before) and black widow pipes without baffles (though the front pipe is cut down to around 13")
Grounding the plug to the engine shows there is plenty spark to the front cylinder.
Any suggestions appreciated.
Thank you.
Hey man ! I probably can’t be of much help as I haven’t worked with the 535 model…I actually do have one I picked up a few months ago that was slowly sinking into a guys front yard, but haven’t had a chance to start in in it to see if it will be a runner again. Just thinking about the Viragos in general, the other V-Twin models have a different cam in the head for the front and rear…not sure if the 535 is like that though, but if so, did you verify the cam (or maybe you used your original cam). For the other models, being off a half tooth doesn’t affect them as the chains stretch over time and cause this. When the timing chain and gear are removed on them, there’s a ton of play in the cam at top dead center so as long as it’s within plus or minus a half tooth they are fine…again, not sure on the 535’s though. You may have already done this as well, but I usually check the compression as well as the valve gap after a rebuild just to be sure everything is set back correct. I’ve also seen some mistakes in the shop manuals (like the Haynes one) that call out the coil wiring wrong as well as giving the valve gap in millimeters, but indicating that it’s thousands on the xv750 manual.
Sorry I couldn’t help much…hopefully one day soon I’ll too have this 535 I got up in the shop and can learn more about that model as well. Let me know what you end up finding for the issue though…I always like learning new things for the different Viragos. All the best ! Steve
@@StevesDIYs Thank you for your response. I checked valve clearance and got 0.09mm for the intake and 0.15mm om the exhaust. Compression on the front cylinder is 150psi. I'll take another look at it. Thank you for the information you were able to provide. I will keep you updated of my findings. Cheers mate.
Since the bike was sitting , won’t it automatically clean that plug had you went riding just like that?
Hello, yes, sometimes they will if the cylinder will fire periodically, but if the plug is really fouled it might just keep getting too wet from the fuel to ever start firing. Sometimes it’s best just to change the plug out I’ve found.
Well I got a Honda Rebel 250 that's bobbed..mines kept cutting out & dying on me when I would go for a ride I noticed mine also runs on one cylinder but also there's a fuel odor coming from the right side so I might have to clean the carb unfortunately
Hey man ! Yep, does sound like it’s time for a carb cleaning if the plugs are still sparking good.
@@StevesDIYs yea I just gave it a new oil change,new plugs,& a relatively new battery but might have to change it again because once the battery is fully charged, the bike starts immediately..but once you turn it off & turn it back on you'll notice the battery starts to drop & it just cranks real high but won't start..the motor has been swapped out before so basically it's a new bike.but those carbs are a pain to go through
on stock carbs, what about if the front cylinder isn't getting fuel ? but you have spark ?
Usually no fuel to a cylinder (for 1st Gens with the stock setup) would either be something wrong with the petcock on the tank like a dirty tank screen, the small secondary screen that is under the float needle seat is stopped up, or the floats are getting stuck up and not allowing fuel to fill the bowl. For really dirty carbs, the jets or the small cross drillings on the emulsion tubes in the carbs can get blocked and prevent fuel from coming up into the carbs properly. The carb diaphragms also have to lift under vacuum to allow the running fuel in so if there are issues with tears or holes in the carb diaphragms, it won’t pull the right amount of fuel. Most times (other than a petcock issue), a good carb cleaning and setting the fuel height in the bowl will get them going again for fuel related issues. Hope this helps a bit and all the best ! Steve
@@StevesDIYs
Ended up being no fuel. The float was up a little high pushing the little needle in that lets fuel into the carby bowl.
Took 5 minutes to fix and she roared to live and has plenty of power now :D
@qwertyui90qwertyui90 👍. That’s great to hear ! Glad it was something easy to fix….All the best ! Steve
Here's a thing... I have a similar issue, but one minute it could be running fine, the next minute the front cylinder shuts off... Completely random, even when cruising. I've changed plugs and it seems to fix it, but a short time after (next day or sooner) the issue comes back... I've swapped coils, and still have the same issue. Carbs were done not long ago... Any idea where to look next?
Hey man ! If it will do it at idle and you have an inductive strobe light (the kind that clamps onto the plug wire like I used in the video), it can help to determine if it’s spark related or carb related. A couple of things to check though would be to make sure the screw that is up in the plug boot is tight and that the resistor inside is not corroded on the ends (if you have the stock plug wires). If you have removed the wires from the coils (for the removable type) also check to be sure that the wire is pushed up onto the pointed contact that is on the coil.
I’ve always stuck with the copper core wires as they are bullet proof for the most part (unless they have touched something really hot and the insulation is damaged. If you suspect that the plug wires are going bad, you can fire it up in a completely dark area with a blanket over the lights for a minute and look for blue hazing around the wires or a spark jumping from the boot or wire to the motor or frame as well.
Sometimes the solder connections inside TCI get weak as well and cause erratic spark, but I always try to rule out other ignition issues before condemning the TCI. Also, be sure you are staying above about 10 bolts on the battery when the motor is running as this will cause the spark to drop out as well erratically.
Hope this helps and all the best ! Steve
Please let me know, what you’ve done to address this !! ?
@@michaelsegarra228 still haven't fixed the issue... I believe it's a stuck float needle and is either starving the carb or flooding it. The stobe light test was inconclusive. Not sure what else to do. Also thinking about going to a single carb conversion too. TBD
Mine started doing this today was thinking was gonna have to rebuild carbs 🤦🏻going to check spark plugs now
Yep, I tend to run mine a bit rich so they start easier (and the bobber is jetted bigger due to the mods so that doesn’t help any either) so my plugs pay the price by getting fouled quicker. I actually just shot another video for the stock bike yesterday when I was prepping it for riding season coming up soon and it too was beginning to foul the plug (they’ve been in there for like three years on that bike though). I haven’t had a chance to edit it to post it, but another little trick I also learned to quickly see if it’s just a fouled plug, if it will at least run on one cylinder, is to pull the plug boot from the plug on the one that’s not firing (leave the plug in the cylinder), but keep the contact inside the boot close enough to the end of the plug top so it will arc. If the cylinder starts firing when the contact is held off the plug just a little then it’s probably a fouled plug. Somehow, creating a small gap above the top of the plug intensifies the spark on the plug where it normally sparks…very interesting and helpful to diagnose an issue, but I have no clue as to why it makes a fouled plug spark to do that, lol.
Hopefully it’s just the plug as I too always dread having to pull the carbs for a cleaning. All the best ! Steve
@@StevesDIYs something is ticking every so often inside my right side carb. Any idea on what it could be ? Bike running rough when choke not on the front cylinder is heating up so it’s not spark plug
@@haydenpike3047 , does sound like the carbs aren’t letting enough fuel go to the cylinder so it may be time for a carb cleaning. The only last easy thing to check would be to take the handle of a screwdriver or something and tap the bowl on the carb that’s giving trouble. Sometimes the floats stick and won’t let the fuel in to the right height if they sit for a bit. Other than that, you might have to remove the carbs and give them a good cleaning.
@@StevesDIYs got it running smooth however while I was riding today it started puking oil from my air hose where my air box used to be and ideas on a fix
@@haydenpike3047 that’s an odd issue indeed. If it’s picking up a lot of oil mist and putting it out the vent pipe that connects to the cam gear cover, it might be missing the baffle plate that goes inside the cover to keep the oil must from going straight out if the hose connection. A little oil (like just a few drops) us pretty normal, but lots of oil wouldn’t be normal for sure.
What battery do you run?
Hey ! For the bobber, I run a small gel battery (225 cca I believe) as it has to sit slightly leaned over inside the right side bag. It easily starts the bike, but won’t crank it long so I keep the bikes well tuned so they fire over in just one or two rotations.
@@StevesDIYs would you have a recommendation on battery type thats close to oem spec? I bought a cheaper aftermarket and it isn’t worth a damn. If it sits for a day i have to charge it before trying to start it, and if it cranks a half dozen times it just drains the things. Once I get it to fire it rides just fine. Can have a 45 minute ride and shut it off and it starts right back up again, but it’s still a rather piss poor battery. Just don’t wanna buy junk again
He doesn't show how he checked the compression, but I'm sure he did that without full open throttle. If you don't do that you have such a reading. BTW< I've never seen such a weird way to let one cylinder running while assuming the compression goes up, because? Next is the explanation of using Iridium, not needed, better to use BP 7 ES, then you can leave the resistor back in the caps.
And here i thought it was gonna be the cdi box, lol.
Lol, yep…when the cylinder cuts out, but then will start hitting for a few rotations, it’s really hard to figure out what’s going on sometimes. These Iridium plugs try really hard to fire even when they are fouled so the erratic hitting makes everything suspect vs. regular plugs that just foul out and won’t spark. Should be good to go again for a few more years (on the front cylinder anyway, lol ! ). All the best ! Steve
@@StevesDIYs are you planning on doing more gen 1 oil covers for an oil cooler? Also you should do a video on how to use the original oil cover and tap it for oil cooler lines. I can't fimd one video out their in you tube land. Thanks!
@@shaunmartin1417 hey man ! I’m actually finishing up a couple of the 1st Gen covers with the cooler ports this weekend 👍. They should be out on eBay on Monday and should pop up if you google Virago 1st Gen oil cover (or at least my sellers site so you can look for them in my listings). For modifying an OE one for the ports, I looked at seeing if it could be done, but I didn’t feel like there was enough metal thickness in the center of the cover to get enough strength for the fitting in the cast aluminum unfortunately. The billet aluminum ones I’ve been making are much thicker in the middle so there’s plenty of metal to have strong threads. I didn’t think it was worth the risk if it blew a fitting off or something.
@@shaunmartin1417 , hey man ! Just letting you know that I made a couple of the 1st Gen oil covers with the cooler ports this weekend. Here’s the link to the eBay listing if interested: www.ebay.com/itm/225002793471?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=sfmcIdagSM-&sssrc=2349624&ssuid=sfmcIdagSM-&var=&widget_ver=artemis&media=COPY . All the best ! Steve
Mine has the same isue
I noticed that my front exhaust pipe is colder then the rear and when I unplug the front coil the bike well stay runing but if I unplug the rear it shuts off that would mean I’m running on only one cylinder or is there another reason it’s doing this i unfortunately didn’t have my tool bag with me so I couldn’t take out the plug. My plain is to remove the plug make sure everything is good and then do an ohm check on the coils id there anything else I should check while I’m down there thank you for any info your videos are amazing
Thanks man 👍. Yep, the spark firing and timing is independent for the two cylinders (separate coils and separate flywheel pickups) so if your front cylinder is cold and you unplug the rear, then the front cylinder is not firing. It’s always good to start with the plugs and pull them to be sure they are sparking which lets you know the coils and plugs are ok.
If it is not firing the front cylinder at idle, but that cylinder will fire with the rpms up and the cylinder gets warm, then it may be that the idle circuit is stopped up in the carb for the front cylinder and it’s not getting any fuel at idle (the running fuel circuit in the carb has bigger jets so they don’t stop up as quickly). If it’s just cold all of the time and never wants to try to fire, I’d also check the compression to be sure you are getting similar readings to the rear cylinder. Hope this helps a bit and all the best ! Steve
@@StevesDIYs it’s the idle jet if I give it gas and then unplug rear bike we’ll stay running as long as it’s getting throttle time to take everything off again lol at least i know it it is I was a lil worried about compression but both cylinder are 120 pretty damn good in my opinion especially not knowing the history
@lucoa-ilnw-5499 Yep, 120 psi compression is plenty for these to run fine 👍. There is still a slight chance it could be a weak coil or fouling plug, but most times for mine if it won’t idle but will fire at higher rpms it’s been a dirty carb jet. You might try turning the mix needle out to see if it’s something blocking it as well as I’ve had that happen too…keep up with how many turns you go out though so you can turn it back in the same if it unclogs though.
@@StevesDIYs i give it another cleaning today lost one of the spring for the pumber but was able to make shift one that works and got it to start on only the front cylinder!! It’s running on both now
@lucoa-ilnw-5499 hey again ! Good to hear you got it sorted out 👍. Safe riding and all the best ! Steve