cutting out at wot

[stainlesscycle]

rode today for 3 hours, was fine for first 2.5 hours..had to limp home after bike started to sputter/booowwaahh at wot - almost stalled up a big hill... i could let off the gas, and it would come back.. i first assumed it was almost outta fuel - i switched to reserve, and swapped the plug for the hell of it, and it didn't fix it..plug looked good, not lean... i got home, added 1.5 gallon fuel, and it still was doing it.. i checked flow from petcock, and it seemed fine...

another thing i noticed is: if i am wot and it's sputtering, i could pull the clutch in, and it would zip right back up. like if i took a load off the motor, it had no problems....

i haven't torn into it, but i'm assuming/hoping: main jet clogged or needle dirty. it could be a reed - but they're only 6 months old..i didn't do a buncha water crossings, and air filter is not terribly dirty...

any suggestions if it's not carb? this may be a moot point, as i'm gonna pull the carb now...hopefully that's all it is..

 

[jostby]

sounds like your sucking a piece of crud up into the main jet. Pulling the clutch in takes the load off of the engine. No load = less fuel needed.
I would rotate the carb and pull the bowl and jets to see if you can visibly see what's causing your problem. Before you rotate the carb and pull the bowl off put a clean paper towel underneath it and drain the bowl, see if anything comes out or if anything is in the bowl drain (main jet access plug) With any luck you will be able to see the piece of gunk that's giving you fits.

 

[stainlesscycle]

damaged carb boot. less than 6 months old. big tear in it. not good. i probably tore it replacing/removing the carb 3 times.....

carb was clean.

 

[stainlesscycle]

welp that wasn't it. switched to another carb boot.
i've set float height (16mm on pwk?), cleaned airfilter, changed spark plug*2, checked carb, checked reeds (i flipped them around to make sure they were sealing - they did not look perfect.....)

it is very hard to start, i can bump it, it'll run for a second and die..

i'm going in the electrical direction. maybe it was more of a loss of spark at wot. woohoo. at least i have a spare coil/cdi/stator.. i'll check kill switch first.

 

[socalscott]

uh oh,
The Phantom strikes again. This issue has many victims and no one solution.
Some dude spent $1400, but the solution was that he took the silencer off and ran it down the road trying to blow it up. Something cleared out and it was fine. Hmm, or was it that a member fixed it and he didn't want the bike back.
Pfff, to many stories. I have one as well, but it doesn't matter. Yours will be unique in the end I'm sure.

Good luck

 

[Silver]

I had an 01 with a similar sounding issue.All though i would also foul plugs.Mine had a high speed miss/sputter.I went the carb route first.Finally settled on it was electrical.Actually tested my theory by taping a timing light to the bars if the timing light goes out while it is missing you have an electrical issue.Mine sorry to say was the CDI.But after changing it ran great.

 

[stainlesscycle]

i tore everything apart that had to do with carburetion and then switched to electrical. i cleaned eveything up, and tested stator. i could find no problems. it works now. i'm gonna do a few shakedown runs this week to see if the problem arises again. i didn't race last weekend, but i have races every weekend from now until november, so i hope it don't pop up during a race..

 

[socalscott]

My 200MXC cut out on top and it turned out to be a coil on the stator.
It was elusive, as it ran fine on level ground. Once under load(grades) in the dirt she'd cut out. Plug got very wet.

 

[Eric K]

I had similar symptoms which were due to a bad voltage regulator. At high RPM the voltage would drop - lights dim and the ignition would cut out causing it to sputter. You could check this out by checking voltage when it sputters.

 

[stainlesscycle]

no voltage regulator on mine. the problem has not resurfaced yet. hopefully going over the entire fuel and electrical system fixed it.

 

[Kootz193]

I've been having the same problem on an 07ec300...still haven't found the problem

 

[stainlesscycle]

i checked and cleaned connections from stator to cdi, rebuilt carb, and flipped reeds around. i figure it was one of those things...problem has not resurfaced yet, and i've put alot of hours on since then..

 

[GMP]

I had the HV wire loosen from the coil on my '03. If loose, unscrew, cut back a few mm and rescrew on with a little RTV.

Also, check your fuel cap. The rubber gasket can swell, blocking the too small vent holes in the rubber. Cut the center out, you don't need it, and check the ball check valve is not stuck. If the rubber is really distorted make a new ring from silicone. This cost me a race once. Heard it happened a lot on '07s.

 

[iancp5]

rode today for 3 hours, was fine for first 2.5 hours..had to limp home after bike started to sputter/booowwaahh at wot - almost stalled up a big hill... i could let off the gas, and it would come back.. i first assumed it was almost outta fuel - i switched to reserve, and swapped the plug for the hell of it, and it didn't fix it..plug looked good, not lean... i got home, added 1.5 gallon fuel, and it still was doing it.. i checked flow from petcock, and it seemed fine...

Happened to me and yes it was a blocked main. Just replace the main if uncertain when you look through it. Sometimes it's hard to tell.