HT Engine Noise Reduction

[happycheapskate]

Can the cardboard piece become degraded and get into the clutch/gears assembly? Has anyone tried flexible plexiglass (like a cheap cutting board) for this idea?

 

[happycheapskate]

For a source of heavy rubber with no metal in it, look for used diesel truck mudflaps. Many are made of plastic now (cheaper), but there are often a lot of 1/2" or 1/4" thick rubber mudflaps that can be had at truck stops or truck yards for $0. There are some new more flexible better quality rubber ones out there too, that are cheap replacements (thinner rubber= less $) They look like truck floor mats.

Yep, as I said earlier - cost $0 for old rubber and cardboard, but the difference...
It's not BS like some speed claims etc.

... Steve

 

[happycheapskate]

AussieJester. This is a fascinating idea. And it would require very skillfull drilling with a LONG drill bit and the engine mounted to a table/base. It would be tedious but sounds like it should work well. Can the threaded rods create "hot spots" inside the cylinder, points of greater heat or uneven heat?

If I tried this I would be extra careful not to break off any fins by using these nuts or rods.

 

[AussieSteve]

happycheapskate, you're not doing anyone any favours with your multiple serial posts, large quotes and reproductions of pics from earlier in the thread. Better to simply post once with several brief quotes and/or questions.
With pics that are already posted in this thread, better to refer to them than reproduce them.
That'd make the thread and others much easier to follow.

Regarding the cardboard, it shouldn't deteriorate in a hurry, if at all. No UV, no moisture, not that much heat.
(Usually I can hold my hand on the clutch cover after a ride.)
Main things are to make sure it's stuck down well and doesn't rub on the clutch locator pins.

... Steve

 

[happycheapskate]

Thanks for the advice.

 

[Motorbike Wanabe]

I had some thermo-ply (dense cardboard used for homebuilding/insulation) from Lowe's and cut smoe small pieces of that to glue to the inside of the engine. I also put some in behind the mag cover also as when I put my hand on that cover there was a fair amount of noise elimnated. I think it helped all the way around and the thermo-ply cuts easily with a set of shears. I love riding my bike around and between rubber tubing between the fins and the thermo-ply, I think it has quieted down a lot. I've got some friends who just ordered the same engine so once they get theirs up and running, we can check and compare differences.

 

[happycheapskate]

I have some 1/4 ID vinyl clear hose left over. I will try slitting small sections of that and pushing into the fins a little for noise dampers. I will try a little piece first to see if it melts.

 

[Motorbike Wanabe]

I think you'll be surprised at the difference. These engines don't seem to get very hot when running so it shouldn't be a problem. Biggest noise reduction that I've found on my engine was putting something inside the mag cover. Then again, I already had the clutch cover and tubes in the fins so that might have been only the next loudest thing on the list. Try it and please let us know your results.

 

[AussieSteve]

I'll try it too. I think you were right though - next loudest on the list.
Just the same, any flat surface can ring easily, so more cardboard in there.
... Steve

 

[happycheapskate]

If someone has access to that thick rubber product which is painted on truck beds (bedliner), they could coat the insides of their case covers with it. I think it should be very heat resistant and durable, but might take some time to cure.