Subject: RE: Exhaust & Carb Tuning
Author: joe jump
Date: Jul 20, 2005, 9:56 AM
Post ID: 1719181768
halc-@comcast.net wrote:
| Joe After a quick peruse of your email I came up with general approach to your problem. Do the easiest thing first. Carbs. Is it gas starved at mid-range? Move the needles up a notch. |
I'm prety sure my needles are raised to max, but I should check
again, and while I'm at it I'll get all the present jetting data.
Though I believe it is a cross over issue. Going from memory, not alway a good thing, I remember my experiences with and w/o x-overs. Without the x-over
So I put on a crossover and ran less restrictive cans (OEM dunstall mufflers) That ended up giving me plenty of UMPH throughout the RPM range. And a louder exhaust. |
So maybe I'm onto something here. Seems that the H-pipe style x-over was
effective on the T-Bikes and continues to be popular with the late-model
injected Tonti tuners too. My previously described idea for a x-over is
basically an H-pipe, but will be located farther down stream than where
it's placed on the later machines and the early LeMans used a x-over up
close to the heads, as did Norton & BMW. Do you think location of the
x-over matters greatly? Also, do you think the diameter of the pipe that
crosses over is critical?
| I believe Guzziology has a write up about the effects of velocity stacks and exhausts. |
I failed to mention my air filters; K&Ns slipped over a set of stacks
that I believe came from a Convert, that have been turned down smooth to
slip into the filters. These stacks are about 2 1/2" - 3" long.
I also didn't mention my dist, which is the standard loopframe single
point unit. Recently I did replace the heavy loop-ended advance spring
with a second lighter spring as recommended by Mark in an effort to get
a linear advance curve more similar to that of a dual point dist. But
I'm pretty sure the advance is maxed out by 4000rpm.
Thanks for responding and appreciate any more insight.
Joe in St Louis
"Junkyard"
850T-Powered Ambo