Checking valves..... please help??

5 replies to this topic
  • 426pete

Posted April 08, 2002 - 02:40 PM


hey, gotta 2001 426 and i am going to check the valves to see if they need any adjusting. How hard is this and what tools will i need for the job? I don't really want to take it to my dealer but i don't want to mess anything up with my engine either. Any help would be greatly appreciated. Thanks guys.

  • motoman393

Posted April 08, 2002 - 03:09 PM


If your just checking the valve clearances, all you need is 10mm socket, a set of feeler gauges (buy a set with a bend in them, the bend makes them easier to get under the cam lobes) and the valve cover is only held on by 2 allen bolts (I am not sure of the size off the top of my head, but it is a common size for MX bikes) The manual explains how to do it well!

If your valves are out of spec and you need to adjust them, you must take out the cams. This can be tricky if you have never taken cams out before. It is not hard to do just take your time and follow the manual (you dont need to remove the radiators, even though the manual says to) Do a search on "adjusting valves"...the 1st time I adjusted mine I posted on TTalk and I got alot of replies, so I am sure you can find that post (it was over a year ago) Good Luck,


  • sirthumpalot

Posted April 09, 2002 - 12:52 AM


Just like motoman said, follow the manual and you'll have no trouble. I didn't remove my radiators either.

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  • dhowell

Posted April 09, 2002 - 05:53 AM



Just wondering how the valve job went. I was planning on doing mine for the first time this week also. Anything tricky to watch out for?

  • Boit

Posted April 09, 2002 - 08:41 PM


Garret gives good advice. However, there is one part of R&R'ing the cams that can be made easier. Taking the cams out is pretty easy and straight forward. Putting them back in and timed correctly takes a little more thought. To make this process easier, I've made a small "V" shaped mark on the chain side plate directly above the cam sprocket punch mark at 12 O'clock. The reason for this is to make a visual mark that you can aim for when slipping the cams back into place. By slipping the cams into the chain while aligning these marks, you negate the hassle of having to remove the cam(s) again just to rotate one, or both, by one or more sprocket teeth to get them into time. If you have a hard time understanding what I've described, it will become clear once you try to reinstall the cams for the first time and then realize that you need some marks to get them back into the proper position. It takes patience just to get the cams back into position and anything that makes it go right the first time helps a lot.

  • Boit

Posted April 09, 2002 - 08:45 PM


Double post removed.

[ April 09, 2002: Message edited by: Boit ]

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