Pre chamber length....

[Pablo]

Yesterday I tried my bike with the pre-chamber length reduced from ~13" to about ~10". Mainly in an effort to gain high RPM power - shift the power band up.

BIG mistake - I lost ALL low end torque, had nothing midrange, took forever to come on the pipe.....and even didn't really seem to have extra power. I even took my new muffler off. No really help. I was very surprised how much a pipe , or rather the pipe tuning effects the pipe.

So I put it back the way it was +3/4".

I guess I got a little wild.

 

[Ghost0]

Guess I should have been a little clearer when I said shorten your pipe to gain more power in the higher RPM range. Just so you know when we were racing Karts we would change pipe length in 1/4" increments not 3" at a time.

 

[jasonh]

lol. Baby steps, Pablo

Seems like a slip fitting would make it easy to adjust to what you're looking for. You could even mark settings out so if you wanted a lot of torque for motoring up a mountain one day, you could easily set it. Or if you just want to go fast another day, another easy change. Once you've got it all figured out that is

 

[Pablo]

Guess I should have been a little clearer when I said shorten your pipe to gain more power in the higher RPM range. Just so you know when we were racing Karts we would change pipe length in 1/4" increments not 3" at a time.

That just makes too much scientific sense. I was messing with aligning the darn thing and trying to keep it from hitting the pedal, the tire, etc. I got the silly muffler back on (you didn't laugh).....I just ate some left over Korean beef, I'm going for a ride after I get caught up on the web.

 

[Pablo]

And we know how this story ended....bike ran like crap regardless....it wasn't the length, it was fuel gone bad....