05 YZ450f won't start!


2 replies to this topic
  • deraleak

Posted March 15, 2012 - 10:57 AM

#1

I bought this used stud of a machine used about 10 months ago. Really powerful bike, has an aftermarket intake, exhaust, aluminum head, and "some work on the carb".
It ran fine for 7 months, but it started having some problems idling. Long story short, it got to the point where it was hard to kick start.
I took the carb off and apart, cleaned it thoroughly, put it back on. Now the bike wouldn't kick at all, but it would pull start behind a quad.
I read up online and thought it might be the valves, sure enough they were out of spec and the timing marks were off on the cams. To fix the timing, I put the bike at TDC and took the cams out, then set them back in where they should be. Put the bike back together, still won't start.
As far as I know the only thing out of place is the valve specs, could this keep the bike from starting??

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • deraleak

Posted March 15, 2012 - 12:06 PM

#2

It's way off timing wise. idk what happened but I'm addressing that right now

  • deraleak

Posted March 15, 2012 - 01:27 PM

#3

I've fixed the timing, re-measured all of the valve clearances.
Exhaust clearance spec is .2-.25 and both valves are sitting between .2-.23
Intake spec is .1-.15 and they are all right above .15 by as much as .03 and .05 mm....

I will make a trip to town tomorrow and try to shim the valves smack in the middle of the specs but as of now, that wouldn't be enough to keep the bike from startin would it?





Related Content

Reviews

Yamaha YZ450F 2017 by Chris.GVS


Yamaha YZ450F 2017
  • * * * * *
  • 1 review
  • Last review by Tommyk_55
  • On January 15, 2017
Forums
Photo

YZ450FX OR YZ450F by MESSMAKER


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  30 replies
Wiki
WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info


Articles
  • 0 replies
Forums
Photo

Chubby dad, looking at bikes , First trip to the orange/black forum ! by Slow_ride


Dirt Bike   Make / Model Specific   KTM   250-530 EXC/MXC/SXC/XC-W/XCR-W (4-Strokes)
  • Hot  28 replies
Forums
Photo

Should I buy this bike? help....... by Numsa Hul


Dirt Bike   General Dirt Bike Forums   What bike should I buy?
  • * * * * *
  • 10 replies
 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.