best expansion chamber

I only have experiences with the SBP expansion chamber, and I can tell you it really makes a huge difference. Once you hit your power range it's like a turbo hitting boost and really kicks you back. I just changed the SBP expansion chamber for a snake pipe and have yet to run that, but I can say the the SBP expansion chamber made the biggest difference out of all mods I did

the sbp is a complete pocketbike exhaust. the banana pipe is missing half the exhaust and its from a pocketbike aswell. the sbp is prone to melt/ leak/ fall off after 20 minute rides. welding it together is the best way.

That's an open ended question.
The best pipe for your bike is one tuned to your needs and engine build.

Motor-bike80- Hello.
So, in general, as the piston covers the intake ports inside your engine, the expansion chamber bounces back some exhausted gas, into the engine, providing a 'super charge' effect. At least that's close.
Why this matters is because the engineering of different pipes will play upon each engine differently.

What engine do you have? How do you ride? These are some things to consider. There are folks here who can give you some real world experience depending on your application.

Good luck!

There is so much more to it than just bolting an expansion chamber to the engine.
My best advice is to study , study , study.... It's all here.
Use the search, Before you spend money.
I have 2 very well balanced stock engines . Both running 44 tooth sprockets.
Both on similar cruiser frames.
#1 bike runs a long torque tube exhaust ( Quiet ).



#2 runs a small pocket bike expansion chamber ( tolerable but not so quiet )



Sounds like your dirt bike.

Both bikes hover around 38 mph WOT.
Both have good torque and manners.

#1 , The quieter of the two , actually gets slightly better economy .
and runs cleaner. At this point.

#2 , to be fair , isn't broke in yet. But seems to have a bit more torque.
Once broke in it is the engine that I will mod.
Ports / head / fine tune the pipe etc.

Now to the most interesting part:

Bike #2 is the bike that gets pulled over.

Never been fined , but it garners the wrong kind of attention from the police....

All the attention that bike #1 get's is thumbs up ' s and smiles ..... Something to think about.

The easiest BOLT ON, in my opinion, expansion chamber is the SBP expansion chamber kit. It comes with what you need to put it together, but I personally welded pipe up. The BEST pipe I think is the snake pipe. I just fabricated one on my most recent build and it's absolutely wonderful and looks great too. I don't have many miles on the snake pipe, but it had a wonder power range, but honestly it was a pain in the butt to make it work because you have nothing to go off of. Arrow motorized bikes sells a bolt on snake pipe, but it's ridiculously expensive.

Edit: forgot to mention with most expansion chambers a longer header gives you more low end while a shorter header gives high end, but you can have TOO short of a header that puts the power range out of reach.

the poopoo exhausts have a nice expansion chamber and price but there is 3 styles.

Very hay with my Voodoo Expansion Chamber. $40. Sounds great (quieter than stock), improved response, top-seed, and fuel-economy. The ONLY issue I ran into was the weld at the head-flange: mine failed there within a couple of weeks of use, but I was able to jury-rig a sleeved-connection between the new (broken) pipe, and a salvaged flange from the stock-muffler. This nearly eliminates induced-vibraiton and I haven't had a problem for over a year of use. I got mine from BoyGoesFast on eBay, but here's another vendor: http://www.jnmotorsbikes.com/product_p/jnm1254.htm

Depends on how well built the bottom end is, but so far I haven't heard of anyone blowing up their engines... most teh failures I've seen are running too lean and burning up a piston or if a pin clip lets go it can ruin an engine really quickly.

I run mine at 10k rpm for a mile each way when I go on my morning taco runs from the shop to the resturaunt and back. i need to keep it at full speed (42mph) the whole time going both directions so I can keep up with the traffic on that street and no problems.

My pipe is a modified KTM50 dirtbike pipe so the bike sounds a lot more like a dirtbike and it's fairly loud but I have the stinger pointing to the ground to help tone down some of the noise. I've gone by the cops a few times but they usually just smile and wave or give me a thumbs up, but where I'm riding I'm not speeding at those speeds, I'm not too slow for traffic, and I'm not so loud that they want to pull me over to tell me to put a muffler on it etc...

motor-bike80 said:

nice, what about the banana pipe, i bought one yesterday, some people say they have baffling in them is that true? if so it it possible to remove it?

Click to expand...

never heard it said that the banana pipes have baffling in them, but knowing the Chinese that are making all this stuff it wouldnt surprise me.

I have one of the smaller banana pipes myself but never run a wire in it to check for baffling, maybe i need to do that just to see now that you mentioned that.

Banana pipe is hardly a 'Genuine Expansion Chamber '.
Just a gimmick, and a noisy one, May give slightly better low down due to less restriction, but you won't get much of a power band compared to a real expansion chamber such as a KTM pipe.

i have a kx65 pipe im gonna get on a bike as soon as i can find the time to get it hooked up, im curious to see how it will act compared to all the other exhaust I've use on my bikes.

Theon said:

Banana pipe is hardly a 'Genuine Expansion Chamber '.
Just a gimmick, and a noisy one, May give slightly better low down due to less restriction, but you won't get much of a power band compared to a real expansion chamber such as a KTM pipe.

Click to expand...

Very true... Most the expansion chamber pipes available for these engines are too restrictive so they might give you a slight boost down low but due to an outlet that's too small it'll restrict top end power and rpm. I made mine out of a KTM50 pipe and it's stinger is nearly an inch in diameter compared to most others that are barely over 1/2 inch. The better expansion chamber pipes like the snake pipe and the SBP pipe are both modified pocketbike pipes that either have the header length modified to run best at a certain rpm range or slip joint fittings so the end user can "tune" it to match their engine's powerband.
There are a lot of moped pipes that can be made to fit which will give really good performance gains and the 60 to 80cc dirtbike pipes will also give you excellent power all the way past the 10,000 rpm mark, these will also give the bike a much more agressive dirtbike sound, even when silenced with mufflers they'll sound quiet but agressive.
if you can weld and have access to a welder, this is the best way to go, but if you need to buy an off the shelf pipe, the SBP is hard to beat. The snake pipe is another really strong pipe but it takes up a lot of space, but these are the only 2 esxpansion chamber pipes I'd recommend for performance other than a modified dirtbike pipe.

I have the SBP and two of the "Snake Pipes" which we used to call the Fatty pipes, the "Snake pipe" doesn't breathe a bit better than the SBP pipe unless the outlet is modified and the header pipe is big enough, I my fastest current bike I was running a low restriction exhaust that I built simply using a stock exhaust header that had the flange port match as well as possible the jug, then I took a large riding mower muffler and drilled the center baffle/diverter out of it and brazed the header pipe to in to make a shorty exhaust that is loud but flows really well, I put the SBP set up on the bike and it lost low down power, mid range pick up and top speed.

I built up the "snake Pipe" with what I was afraid might be a smaller than needed header pipe and I got same results as with the SBP set up after I had drilled six 5/16" holes if I remember right in the silencer end cap and I also removed all the packing from it.

I do believe the snake pipe will out perform the SBP pipe if its modified right but as it is coming out of the box..it isn't a bit better in my experience and I've done the comparison on two different bikes and two different engines, the snake pipe is huge and bulky but the inlet and outlet are still to small for it to provide good high rpm performance, they do work good when modified, Arrow Racing has proven that, but in its stock form it just a big hunk of metal that will be an under performer compared to even a modified stock exhaust, I put it on a bike that was doing 46mph on the flat and with nothing else changed my top speed on that bike dropped to a max speed of only 37mph.

I was very disappointed and knew straight away that it needed a bigger header and a bigger outlet.

the x2 pocketbike pipe or the clamp on proma grand prix get my vote for best pipes. but there is one more im calling the sasquach exhaust because its impossible to find complete. its the large banana exhaust with out a silencer. the stinger and silencer section is missing but complete its awesome. it comes on some bigbore dirtbikes or atv's. its awesome when you add the 16 inches making it completed. best pipe i had till i dented the **** out of it.

i want another to replace my dented one but the sasquach are hard to locate.