I show how I remove the carburetors and airbox in this write-up.
Since I am converting this RS model to an RT, the handlebar throttle and choke cables have to be longer and I show how to change the handlebar cables in the Bowden assembly. I installed them when I installed the handlebar perches as shown here.
I had the air box powder coated. Although the carburetor rebuild was a couple years ago, I rode the bike less than 1,500 miles after the rebuild and they have been off the bike for about two years. I inspected the o-rings and found they are in good condition so no need to do another carburetor rebuild.
Since I modified the engine to boost compression from 8.2:1 to 9.5:1 and had the heads bored for dual spark plugs, I have to change the carburetor jetting. This engine has the same configuration as the engine in my 1977 R100RS that has the CFO (California, Florida, Oregon) configuration, so I use the same carburetor jetting.
When I first got the bike, I rebuilt the carburetors and “updated” the pulse-air system that fed air to the exhaust ports as shown here.
- 13 BMW 1983 R100RS Rebuild Bing 94/40 Carburetors & Karcoma Petcocks
- 13 BMW 1983 R100RS Update Pulse Air System
Here is how I did the work.
And this is a video summary of the procedure.
VIDEO: 1983 R100RS Install Carburetors, Cables And Air Box
Here are a few pictures from the write-up.
Your comments and info on the carburetor slide needles helped me immensely. Thank you.
I actually have the same electrosport plastic slide caliper. Made me smile to see that is what you used.
After setting the idle Jets and then power balancing between the cylinders my r100 1977 is working wonderfully
Thanks from Rodney
Cool beans. I’m pleased this material helped you and the bike is running well.