stock pipes

the best pipe tht is bolt on is the mz65 replica. as for stock muffler mods, widen the stinger diameter to 5/8. you will have to drill through the baffles and the end cap to weld it on, but it will stay realitivly quiet and add a bit more power once tuned to the new flow. as for the mz65 pipe, you will want to add a muffler, they are loud. once you tune the carb to the mz65 pipe, you're gonna love the power gain. i buy the mz65 from zeda, an they are top notch. zeda doesn't sell them thin crap knock offs. their mz65 replica is nice and thick and chrome plated. i've had one tht has been through hell and back, and it ain't even rusting yet. so i keep buying them from zeda, an they ship to me with in a week every time. they do cost a bit, but for the power gain and the shipping speed, it's worth every penny. now you can also make your own, i do tht as well. jaugar has a super website tht has a pipe builder prog you can down load and cut your own cones from print outs you create with the program. it's pretty easy to use and jaguar gives you all the info you need to use it on his site.
 
Ok thanks to all who responded
Is what I did because my racing GT5 s**t motor was so guy less is removed the end cap just a screw on it take off
tap it pull out the guts. I get s**ty take offs but I get speeds of about 33MPH on slight slopes on flat land 26 to 28 sometimes over 30 MPH climbs steep hills on low end about 19 MPH so made a real improvement on performance until it comes to noise pollution it's real loud need to wear earbuds and a good radio station when taking long trips it will drive you nuts.
 
I took the stock pipe, removed the inside muffler tube and shortened it a bit just past where it extends past the baffles and I cut slits in it. The silencer part I drilled another hole on top. To be honest it did make a slight difference, it seems to get up to top speed a bit faster. For me it was a win, it does 31-32 mph with my weight on there 210lbs. no problem. I think on some warmer days I may commute to work on it...………..
 
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Ok, so reading 2 strokes need some sort of back psi. These expansion pipes I seen, are there anything in them? its just a hollow pipe that starts off small, graduates to a larger diameter then back, am I missing something? the key I guess is the length...…...
 
Ok, so reading 2 strokes need some sort of back psi. These expansion pipes I seen, are there anything in them? its just a hollow pipe that starts off small, graduates to a larger diameter then back, am I missing something? the key I guess is the length...…...
With expansion chamber pipes, the stinger is smaller diameter than the header and adds back pressure.
 
Ok, I got it...so really no internals in it, larger open volume then smaller exit pipe to add bp.thanks..
 
The larger part of the expansion pipe, also known as the belly, shoves the unburned fuel back into the jug that would normally pass over the piston at the end of the power stroke. You need to tune the header and stinger together, both are reliant on each other. There are many threads here on tuning exhausts, I'd rather not repeat something already typed out a dozen+ times.
 
Some people cut off the muffler to make it faster but it's really loud and you will get complaints from your neighbors when you start it up. I would definitely get an expansion chamber. It lets more burnt fuel out and then pushes it through the muffler which it's quite but you still get lots of torque.
 
It's not back pressure, If it was, you could increase your power by reducing the muffler tip to 1/8" I.D., which wouldn't work at all. :rolleyes:

Nearly all 2 cycle tuned exhausts work on reflected pressure waves created when the exhaust pressure pulse reaches the reduction cone which reflects back some of the original exhaust "POP!" noise and pressure wave back up the exhaust port, by pushing any air/fuel back into the cylinder in the equivalent to supercharging the intake charge. It also raises the compression ratio a little. It's hard to predict if your tuned muffler will give a broad or narrow torque and horsepower curve increase. A lot of it involves knowing about header length and expansion cone lengths. Tuned pipes take up a lot of room on a bike frame, and would be best on a larger bicycle frame
 
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