RS 80 Carb question

Troy, the 28-29mm carb is what comes on an RS125. I think a carb that size would horribly overcarburate an 80. When I ran the 80 with Tom Hoover (tuner extraordinaire and owner of TECC Racing and YSR Express-three mini endurance overall championships and a long-held (until recently) 80 sprint lap record), I think we ran a 24mm Keihin PWK. Too big a diameter causes too low an intake flow velocity and, subsequently, compromises the Venturi Effect and proper fuel atomization that makes a carburetor work properly.

Troy, the 28-29mm carb is what comes on an RS125. I think a carb that size would horribly overcarburate an 80. When I ran the 80 with Tom Hoover (tuner extraordinaire and owner of TECC Racing and YSR Express-three mini endurance overall championships and a long-held (until recently) 80 sprint lap record), I think we ran a 24mm Keihin PWK. Too big a diameter causes too low an intake flow velocity and, subsequently, compromises the Venturi Effect and proper fuel atomization that makes a carburetor work properly.

Quote:

Originally posted by Chuck Ergle:
Troy, the 28-29mm carb is what comes on an RS125. I think a carb that size would horribly overcarburate an 80. When I ran the 80 with Tom Hoover (tuner extraordinaire and owner of TECC Racing and YSR Express-three mini endurance overall championships and a long-held (until recently) 80 sprint lap record), I think we ran a 24mm Keihin PWK. Too big a diameter causes too low an intake flow velocity and, subsequently, compromises the Venturi Effect and proper fuel atomization that makes a carburetor work properly.

Memory fails you, I think, CE. The GP 125s come with 38mm carbs - Mikuni TMXs with PJs on the TZs, and Keihin 38s with PJs on the RSs.

On the 80s we ran (granted, finishing mostly runner-up to you guys, except in '97 when we won the c'ship), a 28mm Mikuni flat slide for a while and then switched to a 28mm PWK Keihin for later years. As you know from first hand experience, CE, our bike never had perfect carburation -- but using a 24mm carb on an 80 motor will be choking it.

What works best and most reliably? Well, after many years on the bikes and bunch of top finishes (and some wins and DNFs thrown in there, too), I cannot answer this question for sure.

Quote:

Originally posted by Chuck Ergle:
Troy, the 28-29mm carb is what comes on an RS125. I think a carb that size would horribly overcarburate an 80. When I ran the 80 with Tom Hoover (tuner extraordinaire and owner of TECC Racing and YSR Express-three mini endurance overall championships and a long-held (until recently) 80 sprint lap record), I think we ran a 24mm Keihin PWK. Too big a diameter causes too low an intake flow velocity and, subsequently, compromises the Venturi Effect and proper fuel atomization that makes a carburetor work properly.

Memory fails you, I think, CE. The GP 125s come with 38mm carbs - Mikuni TMXs with PJs on the TZs, and Keihin 38s with PJs on the RSs.

On the 80s we ran (granted, finishing mostly runner-up to you guys, except in '97 when we won the c'ship), a 28mm Mikuni flat slide for a while and then switched to a 28mm PWK Keihin for later years. As you know from first hand experience, CE, our bike never had perfect carburation -- but using a 24mm carb on an 80 motor will be choking it.

What works best and most reliably? Well, after many years on the bikes and bunch of top finishes (and some wins and DNFs thrown in there, too), I cannot answer this question for sure.

Chuck,

The PWK 28 is what all the motocross guys say to run on the 80. Your right Linz, the 38 is what the 125 runs.

Anyhow I think I am gonna call my boyz for some tuning help here pretty soon now that I have all the peices to make this thing work.

Brett...Dusty... are you guys out there???

Chuck,

The PWK 28 is what all the motocross guys say to run on the 80. Your right Linz, the 38 is what the 125 runs.

Anyhow I think I am gonna call my boyz for some tuning help here pretty soon now that I have all the peices to make this thing work.

Brett...Dusty... are you guys out there???

Duhhh. They say the memory is the first thing to go...

Duhhh. They say the memory is the first thing to go...

Who's Chuck Ergle????

Who's Chuck Ergle????