Honda GX35 Noise Reduction?

[WheeledWonder]

Silicone exhaust tubing

Has anyone tried something simple, like slapping the 6-inch silicone tubing that Sick Bike Parts sells onto the end of the stock muffler?
How much did it quiet things down from the rider's perspective? From the audience's perspective?

 

[Happy Valley]

Adding a piece of tubing to the stock muffler of these small utility engines offers negligible noise reduction from dB sound meter readings. But give it a try if you'd like and BTW you don't need silicone, common black, automotive heater hose in the appropriate size found at most hardware or auto parts holds up well enough for a trial.

 

[WheeledWonder]

Well, okay...

Thanks Happy.

So...what about ganging 2 or 3 stock mufflers onto the existing stock muffler?

Anybodytrythat?

 

[WheeledWonder]

Other possibilities

So for a rear-mount friction drive setup:

Has anyone tried a mid-engine 50cc muffler like the Standard One Piece that Bicyclet-Engines.com sells?

Did you simply leave it as-is, so the muffler pointed to the front?
Did you bend it around, so the muffler pointed to the rear? If so, how did you effect the bend (weld in a U-turn, use flex-piping, etc.)?

Has anyone gone all-out with their #6 Poo Poo?

 

[Happy Valley]

Yes and no, I've tried similar pipes but not the one from that company.
One issue to begin with is matching the bolt hole centers for the exhaust flange and port size. You would need to measure yourself to ensure proper fit but IIRC these size engines have a 32mm bhc and 10mm round exhaust port. Those sizes are much smaller than most of the ready made products so making or having made your own exhaust header flange becomes necessary.

 

[rawly old]

Gee, they don't come much quieter that a stock gx35
to begin with. I can barely hear mine from 50 feet away.
It's far quieter than the average lawn mower. This is
such a dependable little engine just the way Honda has
engineered it; I really don't want to mess with it.

 

[bigoilbob]

Point quite well taken, rawly old. I sure agree with that dependability part. I wince when I read about the troubles folks are having with their sino powered MB's. I get one little hesitation, one time, when I start out too cold. Otherwise, hot weather, heavy duty climbing, long idle at stop lights, no problem. It runs like a train. And it is quiet compared to many other builds, especially those with no forced air cooling.

I would not do anything that the motor could "see". No tuning, no extra back pressure. But my build is a recumbent tandem, with the motor/gearbox/charging system right behind the rear seat. My wife say it's loud. All moot for now. I'm in the Kingdom of Saud during the week and Dubai on weekends until mid October. But when I get home (for good this time, I always say), I think I will investigate further.

 

[bigoilbob]

Need to call BS on myself, B4 someone else does. When I use a word I should know what it means. MY bike is "sino" powered. I'm referring to the engines I read about, that seem to mostly come from China, that cause so many folks to write in complaining.

 

[Richard H.]

IMO quiet is good, certainly worth pursing doing what you can to quiet the exhaust noise, the issue isn't at idle but at revs. I have a GX35 and while it's a great little engine it often gets left behind in favor of an electric bike I have. The quiet of the ebike has become addictive.

 

[rawly old]

If I addressed all my wife's complaints, I would
have little time for anything else.

ear plugs?