99 RKC, cams & lifters?

L

lastworkerbee

New member
Sorry for a long post. I have 99 RKC with 60k miles, which I bought with 42,xxx miles. I started hearing a noise recently and used a screwdriver like a stethoscope and it appeared to be coming from the cam chest but the chains make some noise when running so it's hard to determine. I suspected cam chain tensioners but checked inside the primary first (was due for fluid change anyway) as I read a post where someone had their compensator sprocket come loose and cause a rattling sound. Everything was fine inside the primary so I adjusted the clutch and primary chain and buttoned it back up. The cam chain tensioners look fine. I did some research here and found that the lifters are suspect on a bike with 50k or more miles so I went back and looked thru the cam plate at the cam lobes and I can see one with spalling (pieces of metal flaked off where the lifter roller rides) and what looks like heat discoloration. So the cams & lifters will be coming out for replacement and I guess my noise is a bad lifter or cam bearings, all of which will be replaced. I suspect that the lifter has collapsed some and is losing contact with the lobe, which is making the noise and the impact is beating the surface of the lobe, or the lifter roller is sticking and rubbing against the cam lobe. I'm looking for confirmation from others who may have experienced this that this is the likely culprit, or asking for some direction on what else I may need to check. I haven't removed the cam plate and cams yet but plan to do that this evening. I have assumed all along that the cam tensioners must have been replaced at some point before I got the bike as they have been fine when I check them at every oil change, but that may not be the case based on what I've read here.

I am on a tight budget, blew my wad buying a car last week, and am only looking to fix the bike, not upgrading anything and frankly cannot afford to at this time. It will outrun my buddy's 08 RKC with 96ci so IMO it runs great, and the tensioners have held up quite well so I don't feel compelled to upgrade those or go to gear drive cams. Please, no "while you're in there upgrade xxx" posts, I've read them all and know the advantages/disadvantages. I need to get it back on the road for as little cost as possible. If anyone has stock TC88 cams in good shape with low miles that they would like to sell cheap or donate to a fellow rider, hit me up. New lifters/bearings/adjustable push rods (maybe) and tensioners are already adding up to more than I wanted to spend right now but I am determined to get more riding in this season as it's been too hot here all summer to ride until recently. If I take the cams out and find they have been upgraded, I will buy the same cams to avoid requiring any tuning. Don't know how much tuning can be done on the MM system anyway. Thanks in advance for taking the time to read this and for any input you can offer.
 
Sorry to hear about your troubles. It sounds to me like you've found the likely culprit with either a failed lifter or a hardening failure on the cam. If you're happy with the bike, there is no reason to upgrade anything at all. As funds are tight and if you don't mind the extra work, I would remove your tank, rocker covers and rocker housing and reuse your stock pushrods. Stock lifters will be fine as will a stock cam unless it was previously upgraded. Since you don't actually know when the cam chain tensioners were replaced, I would inspect them very closely. The inner tensioner seems to wear more significantly than the outer and although they are expensive (+- $55.00 each) it may very well be worth changing them now since it will all be apart.
Another good reason to remove the rocker boxes and support plate would be to check that your rockers are moving freely and therefore not a cause of your problem. Just my .02. Good luck.
 
Thanks for the input. I had considered adjustable push rods and may still go that way but you're right, it makes sense to check the top end too. I'll replace the tensioners when I take it apart, they've held up good but it's cheap insurance to replace them now. Headin to the garage...
 
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