Exhaust drilling?
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Exhaust drilling?
I am wondering if I drill 1 or 2 holes in my exhaust pipe would it be harmful, helpful, or both?? I've got a 1989 Elite E and (as you know by now) am trying to get more performance from it. I am thinking of either sticking a long drill bit into the end of the pipe and go through a good section that way, or putting a couple of holes in on 1 side. I just want to know if that is a terrible idea, and if I will have to up-jet (probably, right?)
I've got a scooter
Re: Exhaust drilling?
its not going to do anything but make more noise and slow it down. you want more power out of that motor, mill the head .030 to up the compression. those motors are rated at 7to1 compression ratio which is low. milling the head the .030in will bring it up to about 9to1 ratio which will increase the torque and rpm
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Re: Exhaust drilling?
If you do this, start using premium fuel because these compression numbers are close to limits of regular fuel's ability to prevent detonation.bakaracer wrote:its not going to do anything but make more noise and slow it down. you want more power out of that motor, mill the head .030 to up the compression. those motors are rated at 7to1 compression ratio which is low. milling the head the .030in will bring it up to about 9to1 ratio which will increase the torque and rpm
Why do people think louder equates to more powerful?
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Re: Exhaust drilling?
I am getting taz's BBK with a head already machined, I guess that takes care of that
I've got a scooter
Re: Exhaust drilling?
NO, his heads are machined to match the bigger bore diameter. They are not milled to up the compression.scootinroundatlanta wrote:I am getting taz's BBK with a head already machined, I guess that takes care of that
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Re: Exhaust drilling?
Ok yeah that didn't fully register at first, I do plan on having the head coming with the kit machined around 0.30 to increase compression. I already use premium, its so danggg cheap for a bike with a 1-gallon gas tank . Also, would it be prudent to also start adding a dollop of octane booster to the premium fuel if I was indeed running a milled machine head with a BBK?
Are there any clutch grab springs available for the Elite E? stiffer ones, I understand, offer a minor improvement in takeoff speed?
And is there anyone out there with an Elite ES pipe that is willing to part with it? It is known as being slightly less restrictive than the E's and that makes me WANT IT!
Are there any clutch grab springs available for the Elite E? stiffer ones, I understand, offer a minor improvement in takeoff speed?
And is there anyone out there with an Elite ES pipe that is willing to part with it? It is known as being slightly less restrictive than the E's and that makes me WANT IT!
I've got a scooter
Re: Exhaust drilling?
You are aware, aren't you, that increasing the bore size will increase compression to start with and with a .030 cut you could be into 11-12 to 1 and even premium pump gas will not handle that and for d*** sure the electric starter will not crank the thing over without using at least 12 volts.scootinroundatlanta wrote:Ok yeah that didn't fully register at first, I do plan on having the head coming with the kit machined around 0.30 to increase compression. I already use premium, its so danggg cheap for a bike with a 1-gallon gas tank . Also, would it be prudent to also start adding a dollop of octane booster to the premium fuel if I was indeed running a milled machine head with a BBK?
Are there any clutch grab springs available for the Elite E? stiffer ones, I understand, offer a minor improvement in takeoff speed?
And is there anyone out there with an Elite ES pipe that is willing to part with it? It is known as being slightly less restrictive than the E's and that makes me WANT IT!
Bear 45/70
'83 Aero 80 X 3
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'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
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Re: Exhaust drilling?
Alright so you're saying I shouldn't go past .025 or even .020?
That's why I mentioned octane booster, its a really cheap way to fake nice gas and I was wondering if that is at all accepted when tinkering with lil old 2 stroke scooters.
I guess I will be using the electric start only to supplement the kick, good thing both work.
That's why I mentioned octane booster, its a really cheap way to fake nice gas and I was wondering if that is at all accepted when tinkering with lil old 2 stroke scooters.
I guess I will be using the electric start only to supplement the kick, good thing both work.
I've got a scooter
Re: Exhaust drilling?
scootinroundatlanta wrote:Alright so you're saying I shouldn't go past .025 or even .020?
That's why I mentioned octane booster, its a really cheap way to fake nice gas and I was wondering if that is at all accepted when tinkering with lil old 2 stroke scooters.
I guess I will be using the electric start only to supplement the kick, good thing both work.
Octane Booster = blown engine, this is from personal experience when they took the lead out of gas. Either by race gas, AV gas or lower the compression. My advise is do the latter, experience on this board has shown that 140 PSI is about the max you want to run on an street motor and that is pushing it a bunch.
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Re: Exhaust drilling?
Ok ok all very good advice, thats why I'm posting on my favorite forum...
What is the ideal milling to get to a compression of about 130? From what I understand, the stock compression for my bike is supposed to be about 70, so we are talking massive increases.
Also, does anyone think that putting a drill bit through the end of my tailpipe will result in any improvements?
What is the ideal milling to get to a compression of about 130? From what I understand, the stock compression for my bike is supposed to be about 70, so we are talking massive increases.
Also, does anyone think that putting a drill bit through the end of my tailpipe will result in any improvements?
I've got a scooter
- scottinscotty
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Re: Exhaust drilling?
Nope... tried it... and welded them right back up... exhaust drill = FAIL
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Re: Exhaust drilling?
ROFL I think I can put this question to bed then...
Lookin for an Elite ES pipe to throw on my E, if you have one give a PM!
Lookin for an Elite ES pipe to throw on my E, if you have one give a PM!
I've got a scooter
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Re: Exhaust drilling?
Don't drill your pipe!scootinroundatlanta wrote:
Also, does anyone think that putting a drill bit through the end of my tailpipe will result in any improvements?
I will make it louder......that is about all.
Some people have reported speed increases.....but those peoples pipes may have had massive carbon build up.
Throwing your pipe on th BBQ or in a camp fire will give better results.
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Re: Exhaust drilling?
I soaked it in lye (draino on crack) and some buildups did exit the pipe, however I have read that people have done both and both have removed carbon on the same pipe, so I think I will try fire as well.
I've got a scooter