WR Valve Adjustment

15 replies to this topic

Posted November 10, 2004 - 03:27 PM


Has anyone done their own valve adjustment? If so would you recommend it to someone that has a "fair" amount of mechanical aptitude and attention to detail? I never had to adjust the valves on my WR400 but my 04' 450 is starting to sound like a sewing machine

Also - has anyone had their de-compression plug pop out? I am considering one of those plugs that they are advertising on the main page.

  • Indy_WR450

Posted November 10, 2004 - 03:41 PM


Yes you should do it. But be prepared to not ride for a couple of weeks after you start. :cry:

  • dirtstiff

Posted November 10, 2004 - 06:51 PM


Pretty funny Indy :cry: :LOL And yes to the decompression plug. I bought the plug and seal offered by TT, it was delivered timeley and cured the plug pop - out problem. Good one Indy. Dirtstiff :cry:


Posted November 11, 2004 - 10:07 AM


:jawdrop:Why am I going to wait for a couple of weeks? Can I assume that my local shop will have all if the shims I'll need? I've also heard that Honda shims are identical, true? I haven't called any shops yet, but what do think the cost to have a shop do it would be? :cry:

I really appreciate the info, this forum is a god send. All of my friends are partial to orange and since I don't even have 1/100th of the carb or jetting problems they do I have no one to discuss valve adjustments with. I do wish however that my valves were as easy to adjust as theirs :cry:

Thanks again

  • Treebark

Posted November 11, 2004 - 03:23 PM


I just checked mine after 1500 miles and they're still in specs, actually on the low side of specs. I thought mine was getting noisier also but I guess that was my imagination. :cry: To do the check is no problem, when need to do the adjustment that's the hard part. I don't think it would be too hard to do for non-mechanical types, just follow the manual and if need more info post it on TT. TT store sells a shim pack ($62)which should have all what you need.

  • mtrablue

Posted November 11, 2004 - 06:57 PM


we'll start with the easy one. the '03 450's had more of a problem with the auto decomp plug than the '04 450's. if you have an '04, don't worry about it. besides, getting the old one out (on purpose) is not easy to do. you'll probably have to remove the radiator.

now for valves. wr's are pretty noisy. there is alot of stuff going round and round in there. most valves have to be adjusted because they have gotten tight, not loose. for the most part the valves are seating them selves and the gap tightens. you might have to "adjust" them twice the whole time you own the bike. it's not a honda. to do it right can take some time. you need to keep track of what parts come from what valve. if you have more than one valve out of spec, you may get lucky and one of the shims may be the one you need for the other. write stuff down! write down the current gap, the current shim size, and the size needed. it'll all blend together after awhile. you may have to waite a couple days for the shim you need. you'll be glad you wrote stuff down.

if the valve (or valves) on only one cam need work, you can put a couple cable ties through the holes in the cam sprocket and hold the cam chain in place. you can lift the one cam up enough to get to the shims and not mess up the timming. don't let the cam chain jump on the crank sprocket or you start from scratch.

also, watch for the "clip" under the cam cap. sometimes it stays on the bearing , sometimes not. it can fall down the cam chain hole.

  • Indy_WR450

Posted November 11, 2004 - 10:15 PM


Mtrablue is right. :cry:
Watch out for the bearing clip!
Keep the chain lifted and tight on the crank sprocket.
Mark the chain and do one cam shaft at a time.
Write everything down and keep the same bucket with each valve!

  • firezwr426

Posted November 11, 2004 - 11:32 PM


I myself choose to have it done at the dealership for 2 reasons: first, it is very important that these specs be dead accurate. Although I am fairly mechanically inclined, I do not attempt to work on things when I am not at least 80% or 90% sure that I am going to get it right.
Secondly, I have a freind who owns a yamaha dealership, who does it for a very good price.
In conclusion, my advice to you is IF you decide to do it yourself listen carfully to people who know whats up for sure. It sounds like the guys that posted right before me know what they are doing. :cry: :cry:

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  • Jackazz

Posted November 12, 2004 - 08:14 AM


To those of you who have done it & had WR's for awhile, how often do you recommend checking the valves? I've only got about 100 miles on mine now, so I'm sure I'm good to go for awhile, but am curious.

  • Oasis_Flame

Posted November 12, 2004 - 10:29 AM


Jack, it really isn't all that hard. Just sounds hard.

Clean the bike and remove air scoops, seat and fuel tank.
Next remove the upper engine mount and breather tubes.
To 5mm allen screws hold the valve cover on, be gentle when removing it. Remove spark plug and TDC the motor using your crank and cam marks. Leave the chain tight for now, grab your feeler gauge (metric&in.) First try .006 on the intake valves and then go up or down from there. Write down what you measure.
Go to exhaust, start with .010 and go up or down and write that down. The feel will be a nice silky smooth feel but not sloppy on the feeler gauge. (i.e.) ex. left=.008 ex. right .011; in. left=.005 in. center=.007 in. right=.004.
Do this first and then send me your lash numbers. :cry:

  • Jackazz

Posted November 12, 2004 - 11:13 AM


OF, thanks for the info, but I'm not so worried about the procedure it'self, just how often I should be doing it.

  • Oasis_Flame

Posted November 12, 2004 - 11:52 AM


Good question, not sure. I would say racing, very often. In my case, 2000 miles ago was the last check.

  • Jackazz

Posted November 12, 2004 - 12:06 PM


Hmmm :cry: I suppose the interval is in the manual, but you know how we men are with manuals... :cry:

  • firezwr426

Posted November 12, 2004 - 01:53 PM


I have mine checked every other oil change, but I run synthetic and change my oil only about twice a year. I ride almost every weekend in the summer, so I rack up the miles pretty fast. I would say better safe :cry: than sorry :cry: if you know mean so do it often. A top end rebuild is alot more hassle than a frequent valve adustment.

  • scheffaa

Posted November 18, 2004 - 02:33 AM


it is fairl easy to do, im 16 and managed to do it fine, as the others have said watch for the clip on the cam and run a piece of wire from the cam chain to the frame rail this will help to stop the am chain falling down the hole.
I have a 01 wr250f and we put suzuki shims in which are exactly the same size, ask bfore yo get them. also the suzuki shim go up by one and yami shims go up in five, meaning you get a more acurate clearance with suzuki shims.
have fun:)

  • John_H

Posted November 18, 2004 - 03:20 AM


All I will say is the 450 auto-deco cam is the best mod IMO.


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