HT Engine Noise Reduction

No need for that - it's all good. The difference really has to be heard to be believed.
Regarding your method, Kim, an old variation on that is to drill a 1/4" hole vertically down through the fins, then thread 1/4" rubber tubing through the holes and finish with a length of 1/8" wire through the centre, bent over at both ends. Works really well. (On dirt-bikes, at least.)
Still, as I said, the rubber blocks are grouse. If some fall out occasionally, I've got enough rubber for hundreds more.

<edit>and the clutch noise when freewheeling with the clutch in is seriously reduced with the cardboard.</edit>

... Steve
 
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Interesting ideas....some of Jim's engines clutches/gears have been loud, mine are relatively quiet. I have no noticeable piston slap.....just loud (natural) head explosion noise!
 
I have done this... except I used some old foam rubber I found in the road. It worked great...
 
Pablo, bad machining tolerances or something, I guess. The day I first started mine, it sounded like it had a broken piston skirt. That never changed, but I got used to the sound and realised that it was normal?.
I considered buying one of Tony, (RSE)'s ceramic coated pistons.
Now, after todays little mods, like you, all I hear is exhaust, as it should be.
On the clutch side of things, I read today that some engines have helical-cut primary gears, whereas others have square-cut. The square-cut apparently make much more noise. Mine are helical. Glad I don't have square-cut.

If things are noisy, the rubber blocks and cardboard are well worth the effort, (and cost, ~ $0).

.... Steve
 
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I also get some rattles that seem to be coming from the clutch. Rattles from freewheeling don't seem to be too bad, although it does make it sound like I am riding a really crappy bike! :rolleyes: I'll give the cardboard a shot.

When motoring and especially engine breaking at higher speeds I do get a higher-pitched rattle which is fairly loud and comes and goes while changing the amount of throttle that I give the engine. This is somewhat worrying but the engine provides good power regardless of the rattle so I guess that it's normal. When I talked to Duane he mentioned that this is fairly normal.

I'll make sure to give the fin padding and clutch cardboard a shot. Thanks for the ideas.
 
Pablo, if you're still watching this thread, I just noticed that one of my pics on the previous page shows my stud lengths clearly. Level with the tops of the nuts w/ a stock head and 1 head gasket.
You can picture how it would look with the 3mm thicker billet head. Only half of the nut bites.
... Steve
 
I saw that. Crud, I forgot to bug Jim about the longer ones.

I'm in no rush, he did say that it would be a week or two and that he'd get back to me.
I wasn't trying to rush you.
I'll get a couple of other things too. I love the slim-line air cleaner. It's high on the list.

... Steve
 
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