Hi all!

Like many others, I’ve had an annoying top end noise in my TC-95. I see tons of complaints on forums (and on the street) about top end noise in TC88 motors, stock and modified. Some say a small amount is normal in these motors. I see a lot of diagnoses’ blaming bad oil pumps, bearings, tappets, rocker end clearance, etc. Yet, fixing these items may or may not resolve the problem depending on the origin of the noise, and the issue may persist. From my own experience, I found a different resolution to my noisy top end. One fairly easy to remedy. I had cam case problems with my 99 FXDL since I bought it. I’ve replaced every moving part in it and the heads. In the end, I still had a tapping/ringing noise front top end. When cold, it’s quiet as a sewing machine. Once the bike warmed up, it sounded like someone rapping the front head with a ball-peen hammer. Nothing made it go away. Ever! Then I thought of one thing I had ignored. Turns out it is related to the rocker arm and rocker arm carrier (support plate). If the rockers swing completely through their arc, to the point they just barley touch the rocker carrier, you get big noise. Especially amplified by the head, which seems to make even the smallest sound ring loud. Yet, only the tiniest, unnoticeable nick gave any clue that there was contact between the two parts. The answer was to remove the rockers/carriers and use a tool grinder to remove a small amount of material where each of the rockers front and rear arms contact the carrier at full swing. Also some addt'l clearance near where for the pushrods come through.
This may be especially helpful if one has installed new valves, new cam, and/or adjustable pushrods. This may cause the rocker arms to be indexed in a slightly different position than when installed with stock components.
The motor is quiet as a mouse now, all 100+ HP of it all!
I am not saying this is a fix for anyone else’s problem, but it took care of mine. Hope this helps someone with a similar problem!

 

Yeah, I have removed the material already . . . but I still get the noise when hot, although it is more valvey than you described, I already had the issue you described and found out the hard way that I had to remove the material from the rocker box cover. I have adjusted and re-adjusted the pushrods to no avail . . . I will continue to hunt down the noise . . .

 

Mine did sound like the actual exhaust valve was making the noise (per stethascope listening). Pushrod clearance up there also are sometimes tight, expecially adjustables. Also rocker end clearance. Mine were .013 which is, I think max recommended clearance. But that does not seem to be an issue. More than that amount, maybe?

Sounds like there ought to be a poll of all TC owners to see how many have top end noise issues, how many were resolved, how they were resolved, and what the root cause was.

 

I had a LMR-2 bypass spring installed in my engine when new. It's always been as quiet as a chruch mouse, no matter how hot it gets..

 

I`ve been thinking about doing that but what gets me is my engine makes the same top end noise when it`s cold as it does when hot. That tells me that more oil pressure will not help, the oil pressure is higher when it`s cold and it makes the same noise.
Normal noise imo, just have to learn to ignore it.

 

My oil pressure was always acceptable. At least according the the guage. Just to be sure though, I also installed a Feuling bupass spring. My pressure was then up a few pounds across the board but that did not alleviate my top end noise issue. Anyway, quiet as can be now, and like new, top end to bottem end.

 

Did you guys change heads or valves? If you did you may want to check the clearance from under the rocker arm to where it touches the top of the valve. Just make sure it's not hitting the corner of the spring. If you went with a larger spring setup, this is likely the issue. If it is indeed hitting, a simple die grinder will remove some of the metal and clear up the noise. I had the same issue.

 

One more thing, before you bolt down the supports, make sure you have rocker clearance on both springs. With the angle of the engine, the supports have a tendency to slide with gravity and be off slightly.Anyway, I hope this helps.

 

Good advice, all!

Since this is an issue that seems to plague many, maybe a thead dedicated to proper top end rebuiliding techniques is in order. Seems that are many conditions to check for that have potential for being problematic.

So far, my problem is gone. But, if it ever returns, I now have a couple of additional things to look for. THANKS!

You never stop learning!