BMW R100RS Jim Cray Keihan mufflers.wmv

1981 BMW R100RS using Jim Cray mufflers, by Keihan.
The oem 160 main jets replaced with 165's, oem air filter. Mixture screw at near 0.75 turns out from stumble. It was at a 0.5 turn with touring Staintunes on, and the 160 main jet.
Note the popping on deceleration. I'm trying to decrease that, whilst tuning the carbs. I have since tightened the exhaust system a little more. Testing will continue.
Fiimed with a MD-80 spycam clipped to the belt of my jacket and as you saw, facing rearwards. The sound of faster acceleration isn't quite so harsh with a helmet on when riding. They don't sound too obnoxious whilst cruising either, and my neighbours are yet to complain of me waking them at 0630 am when I often leave for work.

Category:

Autos & Vehicles

Tags:

• BMW
• R100RS
• Jim
• Cray
• Keihan
• mufflers

[sandmdoyle]

I turned to mixture screws out to one full turn from the 0.75 turn, and the burbling/popping on decel is gone. Back in by the width of the screwdriver blade and the popping is "just" there, very mild though.

Awaiting arrival of 170 main jets, as that is what the designer apparently suggests is the only jetting change required, then tuning the carbs in the normal way to best effect.