making your own end can

[Biker_Dene]

on a 4 stroke do you need back pressure from the exhaust or is that just 2 pokes?

i want to make my own end-can for my bike and wondering would just a empty tube work or do you need pipes inside it?

i could open up my standard can and rip the indies out , it has loads and loads of criss cross pipes inside it but would this just make it worse?
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"RIDE LIKE A KNOB AND YOU'LL DIE"

K9 Suzuki Hayabusa

[0ddball]

It's not really back pressure you need it's gas speed.
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ZXR750L

[Biker_Dene]

hmm can you explain more please mate lol


so will removing everything out of my current end can make my bike perform worse or better and will this cause the can to melt or anything ?

lol

thanks
dene
____________________
"RIDE LIKE A KNOB AND YOU'LL DIE"

K9 Suzuki Hayabusa

[Milo]

[Biker_Dene]

WTF
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"RIDE LIKE A KNOB AND YOU'LL DIE"

K9 Suzuki Hayabusa

[Kickstart]

Hi

Main effect will be to make the bike far noisier. It might well change the jetting requirements.

The average race can is just a straight through perforated tube surrounded by some glass fibre (like loft insulation).

All the best

Keith
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[zx636]

I picked up a standard exhaust from Ebay for my R6 with the intention of ripping it apart inside.

Took ages to remove the internal pipework with lots of grazed nuckles.

End result.

Sounded like a harley with idigestion
performed like it was towing a harley with indigestion.

To set it up properly would have cost in Dyno time.

Far better to go buy an aftermarket exhaust where the manufacturer has done all the hard work for you.

[feef]

2 strokes don't have "backpressure" as such.. what they do have is a shockwave of pressure that echoes off the inside of the fat expansion chamber part of the exhaust, and bounces off the exhaust port just before it opens, causing an additional lower pressure in the exhaust which, in effect, sucks out the exhaust gasses more effectivley, meaning more fresh fuel/air is in the chamber.

in a 4 stroke, a badly designed exhaust system can do a similar thing the wrong way, as an open end can, with no baffling/wadding, can cause an echo to help prevent gas flowiung out.

an effective end can will allow maximum flow, for minimum echo, hence the wadding to act as a damping material.

(oversimplified, so no techies bite my head off here)

a
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[Biker_Dene]

ok thanks for all youe help guys

ill figure something out..
____________________
"RIDE LIKE A KNOB AND YOU'LL DIE"

K9 Suzuki Hayabusa

[quik_d]

i've been thinking about this for ages as i have a 600 bandit exhaust in my shed. I have a standard exhaust on my bike, and i had to re-rivit the end plate on after it worked loose. Now when i did this there is a little tube with holes in it that can be removed, is this a decibel killer kind of thing. There is a big box before the silencer which is the chambers etc so would it affect the bike if this were removed?

thanks guys
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LOOK AT DAT M8 WELL LUSH A PARROT INT IT

[Milo]

Apologies for whatever that post of mine was.
I cut down the quote to the needed bit and typed up a bit explaining that you'd need to re-jet the carb, etc, etc, and then submitted it.
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Shaft drives rule.

[dave172]

[sickpup]

Except it isn't back pressure it's pressure waves. Two very different things.

[SoND]

Since there is a hole in the side of my exhaust, I was thinking about cutting off most of the side, take out the packing and pipes and replacing it with a straight pipe with holes drilled in it. Then put in new packing and weld a new piece of sheet on the side to fix the hole.

Will this in any way help my bike go faster, If I get it jetted and a new air filter?



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[Johnny GSX-R]

Oh dear 'DENE'...............

Its really not that simple.

4 strokes DO require a certain amount of back pressure to be effective. When i had my stockcar dyno'd it was producing less bhp with no silencer than it produced WITH.

When i put the race cans on the XX it was less pokey than with the standard cans

Trust me on that one........ My brother makes his own cans for classic racers such as his MV Agusta 350 and Ducati 160's & 860GTS,, give him a call.

[ZZRman]

Want to burn valves then make your own can.....be very careful

[0ddball]