Really in need of some Dire Advise

5 replies to this topic
  • MotoX352

Posted September 22, 2004 - 10:08 PM


Hey guys Im in real need of advise on what to do in my situation. Bout 4 months ago i wrecked my bike bending the spindle on my crank and totally anihalating the stator and the flywheel. Well Right now im done with spliting the cases everything has been going back together smoothly, except for; The Cams. I have done cams before and that time i marked them so i could have a reference to go from on the clearances. But this time when i wrecked the bike i didnt mark the shims and the buckets so im at a loss of to which goes where. What should I do?! if any of you could help ID SO APPRECIATE IT! :cry: :cry: :cry:

  • Hamish

Posted September 22, 2004 - 11:45 PM


You have to do this one valve at a time.
1.Decide which bucket you are going to put where.
2.Measure the thickness of the top of the bucket.
3.Install the smallest shim you have, install the cam and measure the clearance.
You can then work out which shim/bucket combo will give you the correct clearance for that particular valve.
It's time consuming, bet you wont do that again. :cry:
Next time, go and buy one of those clear plastic parts containers with the dividers in them and designate a segment for a particular valve.

  • RJB

Posted September 23, 2004 - 11:12 AM


Next time, go and buy one of those clear plastic parts containers with the dividers in them and designate a segment for a particular valve.

Now this is why I love this site - thanks for tip :cry:

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  • MotoX352

Posted September 24, 2004 - 03:18 PM


I suppose you have had this problem before? hehe I will give it a shot tommorow let everyone know what the outcome is.


  • grayracer513

Posted September 24, 2004 - 04:07 PM


It's a really, really bad idea to mix the followers (buckets, tappets, lifters) onto different cam lobes than they were on before. It's not a sure thing, but it can seriously accelerate the wear on the cam lobes if things don't match well enough. (BTW, most cam manufacturers will tell you NEVER replace a cam and use the old followers)

Follow Hamish's plan until you can determine which one went where. Because you will be assembling/disassembling the thing may more times than normal, use a lower torque value for the saddle bolts, like say 50 inch pounds (4 ft. pounds)for the testing part, and don't bother with the chain (leave it hang by a wire, or on the other cam while you work this out. Even easier, do it on the bench before the head goes on). If you have a record or a recollection of which shim went where, that will help you. Bear in mind, it could be possible that there will be more than one combination of parts that bring the clearances into range on a given valve, so also get what clues you can from the existing wear "signature" of cam and follower. Go back in and see how it's doing in a couple of weeks, too.

I used to lay my stuff out on my work bench in the orientation the parts belonged in, like an exploded view, sort of. One day I caught my son curiously shuffling through my parts, so I use the organizers now, as well as a screwdriver long enough to reach his knuckles.

  • YZ250F_Rider

Posted September 24, 2004 - 04:29 PM


something to note.

The shims can develop a cup to them over time, so be aware as to which side is up. It can make the difference between a good clearance and one thats too tight from flipping it over.

If you look one side should have a shiny wear ring on it and the other side wont. The shiny wear ring goes down towards the valve stem.

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