Replace Stock Exhaust with Straight Pipe? By massivegood (Read 2,626 times)

[massivegood]

Hello Folks,
Preamble - (the rear bracket on my Roketa M54 250B seems to have cracked and the rear wheel nut came off and the wheel come loose while I was going 60 down hill - I am lucky it just mushed out and lost power and didn't spill me and kill me - not sure i f the nut came loose first and the wheel shifted off the axel and cracked the bracket - or the bracket cracked and then the nut came off...) anywhoo
160 dollars later (a new bracket came last Friday from roketa.com in two days no problem - all you need is cash)
While replacing the rear bracket I seemed to have overtightened one of the exhaust manifold nuts holding on the exhaust - because yesterday I noticed a much richer exhaust note, more power? is that possible? and an occaisional backfire - sure enought one nut is gone and the muffler pipe/gasket is kinda loose at the exhaust manifold. I am in the process of getting mentally ready to remove it all and see if I can replace the stud and I started to wonder - can I put on a straight pipe or some little pipe stub or ?? and get that throatier 'roar' and more power - or will I kill my 250CC engine?
Cheers
rob

[benellibob]

you want to have enough pipe to get past the fan, then you will probably be ok as far as not burning the exhaust valve. you just dont want cold air to be able to hit the closed exhaust valve.

depending on the engine, reducing exhaust backpressure can actually lose power, but i dont know that this is true on these little engines.

also, it will be unbearably loud. you might need earplugs. HAVE FUN!

[massivegood]

i lucked out and the stud was clean gone but the threads seemed to be still be sorta there in the manifold. It was doubly cool that in my box of metric doodads was the exact correct metric stud and two metric nylon lock nuts for it - I screwed the stud gently into the manifold and bolted the muffler back on. i put on lock washers to see if that will help keep it all from vibrating loose. I will also make it a habit to peer through the side cover after every ride and make sure all is snug in the manifold bolt department. I rode into work 40 miles up the mountain over Sam's Gap (3743 feet altitude) and the Roket M54 worked flawlessly. I still want to know more about 'gutted' exhausts and straight pipes and such. thanks, rob

[Alleyoop]

Get a SupperTrapp Muffler Performance muffler they are built rock solid and will out last your scoot. You can ADJUST them for your needs, more Restrictive or more Free Flow just by adding Discs on the End of the MUFFLER.
This is the one I have on my TRIKE.
Alleyoop
www.supertrapp.com/product_sections/cat.asp?CatID=34

[benellibob]

get rid of those nylocks and get real metal lock nuts

[speedracer]

Hey Alley the one made for the ATV sounds awesome. Which model did you actually purchase? Was it an easy install?

Thanks

[madcollie]

Massivegood, gotta agree with Benellibob. Go with with steel.

Alley, that exhaust looks awesome. Can you you give more of a review of it (maybe your own thread) and let us know what it sounds like, easy of install, power differences...

Inquiring minds and all. ;D

M/C