yz426F wont start, Help!!

30 replies to this topic
  • yeti stever

Posted October 21, 2007 - 10:13 PM


ya dont relay want the bike any more will keep riding my kx it smoks and stinks but it always starts even if it take a lil wile will keep looking for a 250 F thou

  • GerryYZF

Posted October 22, 2007 - 10:31 AM


Try to push it to start... some times i have to do that whit my...

  • shawnspawn

Posted October 22, 2007 - 01:33 PM


Ha! push starting a 426 without an auto decomp cam? better be a steep hill, or very, very good friends.... :crazy:

Actually it can be done just not too well, 3rd gear. Probably not going to work though, I think there is more at play here with this bike. I wish I knew what to do with it, I would love another 426 for my dad to try. I suspect there may be a lot of work with the carb, or something more intrusive.

btw did you check that site out? some nice 250fs of various namebrands, almost makes me wanna sell my 426 or get a new bike for the wife.

  • yeti stever

Posted October 22, 2007 - 09:11 PM


no i didint get aroudn to it but i probly will check em out peaec thanks

  • GerryYZF

Posted October 23, 2007 - 09:25 AM


No not on 3rd gear. I do it on the 1st if u try in 2-3 gear u must have speed. I have a 00- 426 whit decomp on the steer. ( dont know if it auto decomp or not.) Follow the start procedure but dont do the last step on the kick. I help me so many times!

Good luck!

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  • shawnspawn

Posted October 23, 2007 - 05:07 PM


When I try to push start on my 426 in first gear, the tire locks up solid, second gear is a little better.

  • hillclimb426

Posted October 23, 2007 - 07:37 PM


find the biggist hill u can and take your bike to the top.get rolling and pull in de-comp and get in third with decomp still in let clutch out then decomp.if it doesnt fire pull decomp in, clutch out and keep trying to get it fired by leting the decomp out.

  • grayracer513

Posted October 23, 2007 - 07:48 PM


To bump start a thumper, start by putting the bike in gear and pulling it back against compression. This gives you a full turn and a half of the crank brfore you hit compression after you dump it in gear. Then run it up and snap it into second without the clutch. The throttle must be completely closed when you bump it, and rolled slowly open if needed. The instant it fires, pull in the clutch and roll it up off idle.

Alternatively, if it has manual decompression, hold the compression release in as you snap it in gear, and release it slowly, disengaging the clutch as above when it fires.

  • yeti stever

Posted October 23, 2007 - 08:51 PM


okay il thanks for that il jsut have to take it over to the big hill and push it a bit .

  • yeti stever

Posted October 24, 2007 - 06:03 PM


i think im goning to take apart the top and do the valves cause that thing has never evin given me one fire and i can hear one of the intake vavles leaking peace thanks

  • shawnspawn

Posted October 24, 2007 - 10:28 PM


probably worth the time seeing as it's pretty easy to get to that level of the engine.... besides it's a lot easier to get rid of a working 426. Or better yet keep it! Good luck man, keep us posted.

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