Silencing a 2 stroker

I would prefer less noise as well but at the cost of any power at all, notta. These motors don't have enough power to spare, anything less would be felt too much I would say.

Try wraping the baffle with cotton or glass insulation, works for me

I did a combination of a remote airbox;

http://motorbicycling.com/f4/remote-airbox-intake-silencing-cheap-10967.html

and an extended silencer on the SBP system (glasspack);


I'm quite satisfied with the results, as there's little to no change in restriction there wasn't any performance loss... actually I shoulda made the silencer even a lil longer but, ah well lol

Just last week a complete stranger said "Hey that's nice and quiet" instead of commenting on the fact it was a motorized bike... confused the heck outa me I tell ya

This is an idea I am messing with. I am still building and have not fired the engine yet so I can't make any claims to it's effectiveness. I offer it up as food for thought. It feels like you could drain a lake when you blow through the utility muffler so I'm not too worried about restriction. The through-put is roughly 5/8". Good luck with finding your solution.

K.i.p said:

This is an idea I am messing with. I am still building and have not fired the engine yet so I can't make any claims to it's effectiveness. I offer it up as food for thought. It feels like you could drain a lake when you blow through the utility muffler so I'm not too worried about restriction. The through-put is roughly 5/8". Good luck with finding your solution.

Click to expand...

K.I.P. I like the new muffler keep us posted

Try some rubber blocks or short pieces of rubber hose in the cylinder fins.

And sheet rubber or an old mouse pad on the gearcase.

all of what these guys said is good advise, if i were you, id take the cap off of your exaust and use a big juice can with fiberglass insulation in it. The bigger your muffler the less restrictive it is and the quieter you can make it. Anyway, play around with it and im sure you can make a setup that will be both quieter and higher performance than stock.

Update and preliminary results. I finally reached the test run stage this week and got to do an evaluation of my exhaust set up. After brazing up a rupture in the manifold where the heat shield nut was welded on this system is incredibly quiet.

It did seem to be a little bit on the restrictive side however. I think the primary culprit was the stock muffler pea shooter tail pipe. I removed the end cap and drilled out the stock pipe. I replaced it with a stubby bit of stainless tubing brazed into place and seemed to have regained some power with virtually no increase in noise.

This set up is probably not for the performance minded but for those seeking stealth it works pretty darn well. I am running a 48cc slant. I have not run things enough to dial it all in but I am happy with the results. The last photo shows the stock tail pipe resting inside of the replacement tube.