4 replies to this topic
  • 426OH

Posted February 03, 2001 - 05:42 AM


I'm a new member on Thumper Talk and this is my first four stroke. But I hope one of you can help me. I took my 2000 426 to my local yamaha shop to get the valves adjusted. When I got it back it couldn't run for more than a couple of minutes and the pipe would be glow red and the radiators would start to overheat. I took it back and they said the pilot screw needed adjusted.I am not sure they know what they are doing. I think they messed up the timing? I'm nerves about riding again ( afraid of seizing )Any Ideas on if I should ride or not? Thanks

  • Sandracer_uk

Posted February 03, 2001 - 06:16 AM


its normal for the pipe to glow red as the bike is on idle.
freak u out tho dont it !
if its boiling the radiator as u ride [ as opposed to sat with the engine running.
try adding a product called ''waterwetter''
and maybe a coolent bottle from a wr400

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

Posted February 04, 2001 - 02:05 PM


426OH, the cam timing off will make it run hot, does the power seem normal or is it lacking. It is normal for the radiator to spew if it is overfilled, and my pipe does glow red. I would have the cam timing rechecked. Good luck. mike

  • Hick

Posted February 05, 2001 - 08:34 AM


Originally posted by 426OH:
I am not sure they know what they are doing.

That is a familiar feeling for many after visiting their local shop. I stopped going.

You may consider checking the timing yourself, the manual is very informative and soon you will be smarter than your local mechanic, if you aren’t already.

Thumpertalk is even better than the manual. Search for the words “valve clearance” or try the “tech” section, here is a link to a good description of the procedure originally posted by Dougie: Valve Check/Adjustment, steps 1-7 is all you need to complete to verify your cam timing.

Hope this helps!

  • 426OH

Posted February 05, 2001 - 11:05 AM


Thanks to all of you that replied.
I didn't have any trouble with overheating until I got the bike back. I will try to check the timing myself to see if they set it correctly. Thanks again to all of you.
426 OH :)

Related Content


05 yz450f not fast enough by RedeyeYZ

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  38 replies

1998 yz400f will not idle. by trolley

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  32 replies


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  30 replies

James Stewart back on a YZ450F by YamaLink

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies

Megabomb Fitment by 288yz450

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply

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.