WR400 - adjusted valves - kick over lockup

Hey everyone... need your help :D

2000 WR400

I' changed my rings, lapped my valves and adjusted them. I did my best to do everything right and I feel I did. When I went to kick it over (not to start it- just a check), I was able to cycle the kick start a few times, with the decompression lever pulled, and then it locked up! :naughty: Now the kick start won't budge, even with the decompression pressed down. What should I do to trouble shoot it?

I'm thinking the decompression lever, maybe?

Or the timing "I" line up... that was strange. I got the pin marks on the cam gears flush with the case like the picture in the manual. Is there something funky I don't know about? How do you line up the "I" - does it take so many cycles - could it be on the wrong cycle? I'm clueless and bummed. :D

I hope I didn't bend the valve onto the piston or something - if that is possible? It never started though.

THanks for your help! :naughty:

Think maybe you've got a ring hung in an exhaust port? I'd start with the easiest thing first- pulling the top end...sorry guy.. :naughty:

That could be - the ring was spinning some when I was trying to get that bitch in. :naughty:

I had that happen to me, but I put some real pressure on the kick and snapped the ring, scored my cylinder.... :naughty:

oh my god! :naughty: that sucked. What did you do after that? Did you fix the damaged cyclinder?

Had the cylinder re-coated. It's fine now. Good luck on your motor. But you know it happens to all of us sooner or later.

First of all there is no exhaust port in the cylinder on a 4 stroke. Most likely your valve timing is off. Can you rotate the engine backwards with a wrench on the flywheel? If so pull the cams and redo the timing. If not then I would pull the head and take a look at the cylinder.

Think maybe you've got a ring hung in an exhaust port? I'd start with the easiest thing first- pulling the top end...sorry guy.. :naughty:

&%$#@! are you talking about :naughty: This is a 4-Stroke not a 2-Stroke!

Here's a stab, make sure you are looking at the "I" mark that is in "HI", not the other "I" mark. Start there and try again.

I was imagining the cyclinder in bed last night, and I was like wait - the cylinder wall is smooth all the way up to the top... what the? I'll try PBD Blue's solution. Thanks, Joe

It would be good it you can tell us what's gone wrong and good luck on soting it out.

How many times did you kick it over before it locked up? If it was a valve hitting a piston it should have locked up with the first full cycle of the engine, and you should be able to rotate the engine backwards like PDBlue said. If you only kicked once or twice that's probably it. If you kicked more than that before it locked up it's probably something else jamming, unless the timing jumped.

Didja remember to release the cam chain tensioner? If not, you might have skipped the cam timing or balled up the chain.

Today, I opened up the timing cap and rotated the crank counter clock wise (the arrow direction). It's free, but every time I go over a zone (the "F28...) it makes a light shhh (like its rubbing - maybe normal?) - not sure if thats part of the problem.

I did ball the chain up once finding the "I" top dead center when adjusting the timing - I was like what the is going on. Found out that could happen and corrected it. Maybe that tensioner didn't pop out (almost certain it did). I'll just wind it up some and see if it spins out on its own.

Any tips?

I just kicked it twice I believe.

Okay, I double checked to see what's going on.

I turned the crank with a wrench, counter clock wise, while watching the the timing indications. When it goes past the letters "F5BF" it makes a light shhh/kk noise but will spin all the way around and around. When I move the kick start it locks up right around the letters "F5BF". I'm guessing its the lobes pushing the valves at the wrong timing. I'll open it up and see if I screwed up somewhere or if it's balled on the chain.

son of a bitch :naughty:

thanks for the tips

Think maybe you've got a ring hung in an exhaust port? I'd start with the easiest thing first- pulling the top end...sorry guy.. :naughty:

Impossible on a 4-stroke......unless it broke and ended up on top of the piston!

OK, here is the latest :naughty: :

I checked the timing. It seemed to be off, so I set it again like I did before E's to the left - dots on the outsides/flush. Then I turned the crank around one time to line up with the "I" again. I noticed that it was off again, but it's not. I guess it depends on how many revolutions to the "I".

How do you know which is right?

Anyway, with the kick start I noticed it locked up when the exhaust valves were pushed at the maximum. I could turn it with a wrench/ratchet but makes a light grinding sound. So, I thought there might be the wrong pad/shims under the caps. I took the cam off for like the 6 th time (serious) and inspected the caps and pads - seemed fine. :D


I left the cam off and held the chain with my hand, so it wouldn't ball up the chain. I zip tied the decompression lever down (the pin pushed the valve open to release air). I tried to push the kick start and the same shit happened - lock up. I guess that eliminates a timing problem..?

I didn't want to have to pull the cylinder! :D

I don't see how it could be the rings. It's locking at the same point too (F5BF point on the timing look hole).


&%$#@! are you talking about :naughty: This is a 4-Stroke not a 2-Stroke!

Chill the F**** out dickweed. Slip of the tongue. Sheesh. Trying to talk to 10 people at once here AND solve the problem of world hunger!

Thanks for keeping us on our toes. :naughty:

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