2 stroke exhaust....

[jmr3394]

Can someone explain to me how having a muffler with an expansion chamber improves performance? Also how much are they usually and where can i get on for a 66cc china? Thanks, JMR

 

[Venice Motor Bikes]

Check 'Sick Bike Parts' (they have a ad on the side of this page) they sell the pipes & will explain how they work.

 

[bairdco]

this guy can explain it best: http://www.kreidler.nl/artikelen/performance-tuning-graham-bell/performance-tuning-graham-bell.pdf

 

[MxG]

witch one would b better for a gt5 80cc

sbp one
Sick Bike Parts


or this one from spookytooth
Expansion Chamber Exhaust

 

[BarelyAWake]

I've run them both... well sorta lol - I've the SBP one and a buddy has the Spooky and I can tell ya this, the Spooky one is LOUD! There's also the problem with the Spooky one that w/o a head pipe there's no real easy way to adjust it to fit your bike if it hits the pedal crank. Expansion chambers also need some length of head pipe for maximum performance... how much this effects it I'm not really sure because although my engine and his are identical, his is stock other than the pipe *shrug* The Spooky one is easier to mount, it's just a "bolt n'go" if it fits... whereas the SBP one is a true full-length exhaust system that requires a little customization (trimming pipe length, routing) - but it's nice that you can customize it...


Both of them do provide some performance gain, but given the problems with the Spooky one (may not fit, no headpipe, crazy loud, no rear support) I'd vote SBP - but you may like loud and it might fit perfect on yer bike - your call, ANY expansion system is better than the stock can

 

[Tim_B_172]

If you can weld, go to Ebay and search for "pocket bike exhaust". There are a few pipes with chambers for sale, but the pipes are weird shaped and so you would need to cut and weld to make it fit on you're bike. It's cheaper that the SBP pipe and some of the chambers appear to be about the same shape as the SBP one, that's the only reason I suggest it.

I'm just waiting for pay-day to buy one.

 

[sajoe]

I have the SBP. I got it to where it fits perfectly on my bike and welded it up. The performance increase was unbelievable and not too loud.

 

[Kevlarr]

If you can weld, go to Ebay and search for "pocket bike exhaust". There are a few pipes with chambers for sale, but the pipes are weird shaped and so you would need to cut and weld to make it fit on you're bike. It's cheaper that the SBP pipe and some of the chambers appear to be about the same shape as the SBP one, that's the only reason I suggest it.

I'm just waiting for pay-day to buy one.

One of the things you can do with an ebay pipe, the original exhaust, a welder and some imagination.

 

[BarelyAWake]

http://motorbicycling.com/f3/29-ebay-pipe-hour-welder-11950.html#post114495 Kevlarr's thread for the above

http://motorbicycling.com/f13/expansion-chamber-1467.html Some good readin' & summore examples;

http://motorbicycling.com/f13/pocket-bike-expansion-chamber-60cc-engine-9831.html

http://motorbicycling.com/f13/pocketbike-pipe-48cc-works-excellent-2491.html

Expansion chambers are about the best bang for the buck yer gonna get in performance mods on these two-smokers