odd problem

some times my 99 WR400 will take about 15 kicks to start it and then it will not pick up any revs, like a total bog it just will not come of idle. also the header starts to heat up and glow in a matter of seconds. other times it will start first or second kick and run great.

i have a JD kit and im using the blue needle on the 3rd position, 170 main jet and a standard pilot jet.

i also just put on a CRD pipe, the engine has just been rebuilt and i have checked the cam timing and it is spot on.

it seems like something to do with the ignition but i don't really have a clue, it could be any thing.

i have gone through the bike and checked every thing i could think of and come up with nothing. i hope you guys can help

thanks Simon

Have you cleaned your carburator and checked your float level?

It may be the igntion CDI box. If it runs well sometimes and not others the CDI unit maybe failing. :)

yeah i have striped the carb cleaned it and checked it out every think seems ok

i hope it is not the CDI because they cost so much. does any one know if or how you can check the CDI.

exhaust valves hanging up?

I don't think you can check the CDI. THe best thing is to swap CDI's w/ someone (even put yours on their bike as well).

I JUST SOLD my OEM CDI for $50.00( :)?)

it doesn't seem like the exhaust valves because it only happens some times not all the time.

i also don't think it is the CDI any more because i think if there is a problem with it, it wouldn't run at all.

so im back to square one and im clue less :)

it doesn't seem like the exhaust valves because it only happens some times not all the time.

>> it may not be ALL the time.

ok ill check it out and post my findings tommorow

thanks :) Simon

Just a thought here, but everytime I park the bike for any lenght of time I always push the kickstart lever till the bike is at TDC so all of the valves are in the closed and relaxed position. If the engine sits with the valves open during the week it could hang a valve open , especially if the bike is getting older. My .02 -- WR Dave.

my old man says that it can't be the valves sticking because the engine would still pickup some revs if they are hanging. we think i could be the ignition pickup has gone wrong somehow and made it to retarded. but i don't think there is any adjustment on the pickup so im not sure what to do. i don't know how to check it and i don't have a flywheel puller/remover. :)

any help will be greatly appreciated because im going insane trying to figure this out.

thanks. :D

I would take a look at the insulation on the wiring of the bike,being an older machine it is quite possible that you are getting a short in the ignition circut wiring from wires rubbing against the frame work and exposing a wire some where(or a break in the wiring due to repeated bending turning or pulling forces on the wiring)incluiding the kill switch wires,try a multi meter on the circuts whilst turning the bars and twisting the connectors and wires to see if you get any change,i know of a two stroke that did a similar thing recently due to a wire lightly grounding against the frame!

I'd run the bike for about 10 min on a batch of 2 stroke at about 50:1 (I use an old fork oil bottle, the tip fits nicely in the fuel hose on tyhe carby). If you have a sticky valve, this should cure it. If you have access to a leak down tester, I'd use it to see if it's compression related. I'd also check the resistances of the stator. Had a similar problem with the 250 2 smoke, turned out to be a crook stator.


i have checked out the ignition coil and stator, there was nothing wrong with them so this morning i took the bike to the shop and they said it was the woodruff key and it had broken so the flywheel has slipped and is causing the problem. hopefully ill get the bike back on Tuesday or Wednesday.

WOW............??? :)

Never knew the 400`s performed that trick! :)

i think the problem was caused by faulty workmanship, or something like that. i think they did not torque it up properly when they rebuilt the engine that's why they are doing the repair for free :D or im there best customer because they don't get much business and i just bought 2 bikes and about 2000 Euros worth of parts from them. :)

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