bryan b Posted May 14, 2012 Report Share Posted May 14, 2012 Howdy all, got a strange one here. My buddy has a 2004 shee, engine is all stock, we put a set of FMF Gold Series Fattys on it over the weekend. We re-jeted with a 300 main 1st, that was a bit rich so went to a 280 main(didn't have the 290 jet available). That seemed to be working good, it ran great and plugs looked good. Pilot was left at 25. tjis bike has done something int he past that i kinda thought was strange. When its cold after you start it up and warm it up it will run a bit sluggish which is kinda normal till she warms up but it would make a small pop, more like a big gush of air soon as it warmed up. After it made the little pop it would run great. but before that it would be sluggish. Any way on to the story here. We took both the Shees out for a little spin, Both were running great. We ran them for prob 10 miles on the dirt roads just goofing around. Got back pulled the plugs and they looked a nice chocolate brown color. They were brand new plugs also FYI, Any way we let the bikes sit for about an hour then fired them back up and went to go for another spin. My buddys 04 Shee that we just put the pipes on made it about a mile running great then it was like you just flipped a switch and turned off the power band. We brought it back to the shop(running). Pulled the plugs and it had fowled the left cylinder. So we put a new plug in. it ran good for bout 30 sec and then quit firing on the left and backfired a few times. So we did the following in this order. Compression test left side 105psi.......Right side 105psi Leak down test.......Held 10psi for 10 min(may have lost 1/2 lb) Pulled reeds and inspected, they are fine. Pulled carbs off, checked floats, checked jets, cleaned. Checked choke tube, its on there and clear and no splits crossover tube is there and tight checked spark on both caps, good blue spark swapped plug wires new plugs in both sides unplugged tors brain box and tors connections. None of the above made any diff. We kicked on it for mabe 20 times and it would not start for nothing. Pulled the choke out and fired right up. Died again, again we kicked it a few times no start, pulled choke out and fired right up. then I was checking to see what the exhaust felt like at about 1/4 throttle. the left bank is just a light stream of air, the right bank has a good pressure feel to it. at idle i can hold my hand over the left exhaust outlet and the bike will still run, if i hold my hand over the right bank the bike dies. it also backfires out the left bank some. So, what ya all think here? Ran out of time last night to swap parts from my shee to this one for trouble shooting but i am kinda thinking fuel delivery issue. Reason being you have to choke it to start it now even when warm. elevation is 760 ft only mods are the fmf pipes and no air box lid. uni filter still has tors Quote Link to comment Share on other sites More sharing options...
Phelps Posted May 14, 2012 Report Share Posted May 14, 2012 imo 105lbs at 760ft is too low. the added fuel from choking is increasing ring seal and upping the compression short term. Quote Link to comment Share on other sites More sharing options...
bryan b Posted May 14, 2012 Author Report Share Posted May 14, 2012 you think thats the prob even tho it was a sudden change in performance? It was just like you hit a light switch, not a gradual thing. Quote Link to comment Share on other sites More sharing options...
shakar Posted May 14, 2012 Report Share Posted May 14, 2012 maybe unplug tors box ,....check the ebake sometimes that will stick and cause a shitting rev limiter feel. carbs together correctly as each one is different .you may be a lil lean ontop and most aftermarket pipes call for a 27 1/2 pilot. ..... goodluck Quote Link to comment Share on other sites More sharing options...
Phelps Posted May 14, 2012 Report Share Posted May 14, 2012 could be ignition, or fuel. a weak stator, or coil could cause it along with the mentioned tors system. i would def have a topend rebuild in mind even if it turns out to be something else. you can test the stator and coil via owners manual. Quote Link to comment Share on other sites More sharing options...
bryan b Posted May 14, 2012 Author Report Share Posted May 14, 2012 (edited) we already unplugged the tors system, including the black box. didnt have the 27.5 pilots till today.We have a problem with the local Yamaha dealer not ordering the right shit. we will put them in also tonight along with the 290 jets. Im gonna go through the carbs again tonight and see if i can find anything again. Other than that im gonna start swapping parts 1 at a time from my bike on to this one and see where i end up. Was hoping to make it to winter before we did the top end. Edited May 14, 2012 by bryan b Quote Link to comment Share on other sites More sharing options...
BUILDER Posted May 14, 2012 Report Share Posted May 14, 2012 105 is weak but the bike should still run fine but as you know it is going to need a rebuild soon. First thing I would do is swap the cdi box from yours to his and I bet that will fix your problem. Sounds like the CDI to me I lost one on my daughters bike last riding trip and it did the same thing. I have seen a few other bikes that have doine that also. As far as the pilot goes with just the mods you have the stock pilot should be just fine you can put the 27.5 in if you want but I doubt you really see any change with that. Good luck. Quote Link to comment Share on other sites More sharing options...
yamahaty Posted May 14, 2012 Report Share Posted May 14, 2012 try dissconnecting the parking brake, mine did the same thing and that was it Quote Link to comment Share on other sites More sharing options...
bryan b Posted May 14, 2012 Author Report Share Posted May 14, 2012 just talked to my buddy. so far he has swapped out the CDI and the coil from my bike to his and no change. Next up is disconnect the parking brake and if that dont work swap carbs. Quote Link to comment Share on other sites More sharing options...
fastbanshee8 Posted May 14, 2012 Report Share Posted May 14, 2012 Check your stator. Maybe the ignition side is going out. Quote Link to comment Share on other sites More sharing options...
Finch Posted May 14, 2012 Report Share Posted May 14, 2012 i just fought a similar problem for 3 weeks tried everything mentioned my outwears were clogged even after cleaning them they must of stil had some oil on them and dirl just clogged them solid every time i went riding and you didnt mention cleaning the filter maybe try running it with out them and see if it gets better Quote Link to comment Share on other sites More sharing options...
BUILDER Posted May 14, 2012 Report Share Posted May 14, 2012 just talked to my buddy. so far he has swapped out the CDI and the coil from my bike to his and no change. Next up is disconnect the parking brake and if that dont work swap carbs. I thought you had all of that stuff unhooked. That is one of the first things to try if you are having troubles like this. Quote Link to comment Share on other sites More sharing options...
bryan b Posted May 15, 2012 Author Report Share Posted May 15, 2012 I thought you had all of that stuff unhooked. That is one of the first things to try if you are having troubles like this. Didnt have the park brake unhooked but had the Tors unhooked. And we are running a clean air filter. When we have it int he shop we are starting it with out the air box on it and makes no diff. It has got a little more confusing. We put his coil and stuff back on his bike, with the old plugs and so on. Did not change anything else and hooked up the park brake again. It fired right up and ran like a champ.(WTF) he took it out for a spin and it ran great. BUT...........after 10 min of riding it now runs like a streak of SH_T in the pipe but loads up on the low end and pops out of the left bank. so we have now done a 180 on where the problem is and we have changed nothing. We will get it figured out but damn this is nerve racking! Quote Link to comment Share on other sites More sharing options...
shakar Posted May 15, 2012 Report Share Posted May 15, 2012 any luck figuring out the prob??? Quote Link to comment Share on other sites More sharing options...
bryan b Posted May 15, 2012 Author Report Share Posted May 15, 2012 any luck figuring out the prob??? nadda, look at my post just above yours. we kinda fixed some of it but not sure what the hell we did lol. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.