Has anyone had this problem with their yzf

5 replies to this topic
  • goldy1980

Posted January 29, 2009 - 06:15 AM


I have bought a yz400f 98. I have just fitted a new carb and changed the spark plug but now when i kick the bike down and find the hard spot, pull the decompression lever in, let the kick return to the top, release the decompression lever, and kick, i don not get a full stroke. the kicker only goes down about 5" then finds the hard spot again. Can anyone help?

  • jrny426

Posted January 29, 2009 - 06:35 AM


Pull th decomp lever in and then continue the kick a couple of inches down on the kick start relase decomp lever.. retun kick start to top a then try it.The way your doing it doesn't open the exhaust valve.

  • matt4x4

Posted January 29, 2009 - 06:38 AM


ok, finding the hard spot, pulling the decom lever and releasing it really does NOTHING - it leaves your piston sitting on the upstroke of the compression stroke. The you load up the kickstarter which is the 5" you're talking about and compressing the gas in the cylinder again.

What you have to do is:
Push kickstarter through to find hard spot.
Pull Decom lever & press kicker about 2" more.
Release decomp lever.
Release kickstarter.
Now kick it.

It should travel through 1.75 engine revolutions before hitting the compression again, at which time there's enough momentum behind everything to get things rolling.

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  • jrny426

Posted January 29, 2009 - 06:38 AM



  • grayracer513

Posted January 29, 2009 - 07:08 AM


A movie is worth a thousand pictures:




Posted January 29, 2009 - 12:39 PM


huh...ive been doin mine a hair differently but same principal...

1.i find the hard spot
2.then let hte kick starter all the way up
3.pull in the decompleve a bit and then move the kickstart lever down until i feel hte piston move for a lack of better terms.
r4.elease lever and allow kick start to com full up
5.thn i kick full stroke

but i thinkim gona try it the video way instead seems faster

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