My YZ is cursed now seized!

6 replies to this topic
  • bushy

Posted June 03, 2004 - 01:47 PM


So today I start it up, and its smoking a little. I just oiled my filter, so I figure its that. I rev it few times, and call it good. When I hit the kill switch the engine, I heard a crack sound. Kickstarter is seized. At this point I start to worry, so I push the bike back and forth to see if its just the kicker locking up. No luck. I have 4 rides on this oil and its not leaking anywhere, and the engine was totally rebuilt last may at probally ridden a total of 50 times since. :thumbsup: :lol: :lol: :lol: ;) :mad: :awww:

Even though I'm only 14, I treat this bike with great care. Wash it and change the oil every week, clean and oil the filter every 3 rides.... what did I do wrong!

Ive had nothing but stuff breaking on this bike, I'm pretty sure I'm goign to sell it once I fix this. But then I'd have to go back two stroke :lol:

  • sirthumpalot

Posted June 03, 2004 - 02:59 PM


Can't tell what you did wrong (if anything) until you take it apart and see what broke and why.

  • PumpkinHumper

Posted June 03, 2004 - 03:36 PM


Check your kickstarter. My buddy had something go haywire on his WR400 kickstarter. Similar symptoms as you describe.

That is one thing to check. Does the motor turn over at all. Can you roll it with the bike and gear and the compression release pulled in. Will it turn over?

You need to determine if the piston / cams are locked up or if something in the tranny / clutch / kickstarter is the culprit.

Little more info would help.

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  • Ga426owner

Posted June 04, 2004 - 09:46 AM


I went thru this with a 426 try to roll start it in 3rd gear & see if that frees up the kickstarter.

  • bushy

Posted June 04, 2004 - 12:24 PM


Took off the right side cover, nothing wrong there. Took of the valve cover, while the engine at TDC the lobes on the back of cams are not straight, they form a right angle. How did my chain jump so many teeth! Hopefully I dont have any valve damage, after reading a few posts on here I'm going to pull of my head :thumbsup:

The cam chain tensioner looks fine, and the sprockets arent not worn. There is no lack of luberation. How did this happen! It was only idling in the shed, and freezed right after I pushed the kill switch.

  • sirthumpalot

Posted June 04, 2004 - 01:51 PM


Maybe you got away with relatively little damage since you hit the kill switch before it had a problem. You need to remove your flywheel and check the sprocket on the crank. Typically that is the first sprocket to show wear. Also check out your tensioner and the length of your cam chain (is it longer than spec from wear?).

It's also a good idea to inspect the valves closely and make sure they aren't bent. The piston too. Let us know what you find.

  • bushy

Posted June 04, 2004 - 02:24 PM


Well the tensioner is good, and we fixed the timing on the cams. Put nessaicary parts on, and tried to kick it over to see if I had the hard spot. No luck. Intake valves are guarenteed to be bent, possible piston damage and/or exhaust valve damage if they hit eachother. :thumbsup:

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