• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

  • Beginning April 1st, and running through April 30th, there is a new 2024 BMW MOA Election discussion area within The Club section of the forum. Within this forum area is also a sticky post that provides the ground rules for participating in the Election forum area. Also, the candidates statements are provided. Please read before joining the conversation, because the rules are very specific to maintain civility.

    The Election forum is here: Election Forum

new rear drive

jkmolt

New member
I'm am thrilled to death with the new lower gear ratio I just had put in my rear drive for the R1100RT that's the tug for my EZS Summit sidecar. Only rode it home from the shop that did the work. It became obvious pulling away for the first time (up a slight slope) that slipping the clutch was a thing of the past. 32 mph @ 4000 rpm is perfect for riding in the city. Only got up to 50 mph for a short distance and while that's too slow for 5th gear it was obvious that using 5th gear at around 60 mph will definitely be possible. With stock gearing, starting up almost any incline needed the clutch slipped. On the highway, 4th gear was necessary to run 60 to 65 mph with had the engine running at 4500 to almost 5000 rpm. To actually used 5th gear I needed to wind it up to approximately 70 to 75 mph to be able to use 5th without feeling like it was almost lugging the engine (maybe not the correct word). Basically it was just working the engine way too hard for my liking.

Even though temps here are still in the 30's it's supposed to get warmer to the 40's in the next few days. When it does, I'm going riding to find out what the 5th gear really feels like.

This is one of the earliest Christmas presents I've ever given myself.

Absolutely love this rig.
 
New final drive

What is the new FD ratio? Who did the work?

Sorry to have to tell you that I don't know the new ratio. I have great faith in Cheshire Motorsports here in Portland, OR. Simply told Daric what I wanted and left it to him. His only comment is that the RD was now quite close to what the old BMW's designed for sidecar use had.If your anywhere near Portland, OR I highly recommend Cheshire Motorsports.
 
Sorry to have to tell you that I don't know the new ratio. I have great faith in Cheshire Motorsports here in Portland, OR. Simply told Daric what I wanted and left it to him. His only comment is that the RD was now quite close to what the old BMW's designed for sidecar use had.If your anywhere near Portland, OR I highly recommend Cheshire Motorsports.

I believe to 850 oilheads had a lower rear drive, also some of the GS models had different ratios.
 
Fyi

My wife has an '04 R1150R with an EZS chair. Granted it has the six-speed tranny, but she runs the motor for hundreds of miles at a time around 5000rpm's. If she drops below 4500, she downshifts. She finds that's where the bike runs best.... although the gas mileage does suffer a little bit.
 
new rear drive gears

My wife has an '04 R1150R with an EZS chair. Granted it has the six-speed tranny, but she runs the motor for hundreds of miles at a time around 5000rpm's. If she drops below 4500, she downshifts. She finds that's where the bike runs best.... although the gas mileage does suffer a little bit.

My '99 absolutely loves 4500 rpm. Anything much less and it starts to act like the old VW Beatles. Hit the slightest grade and it's down a gear. 4500 rpm and almost all grades on an interstate are no problem.

I find that with the new gears I run at about 65 mph at about 4300 rpm. Still really enjoying the new ratios.
 
I replaced the final drive on my R1100R rig with one from a R850R. This lowered the ratio from 3:0 to 3:36. It made a huge difference. Before the change 1st and 5th were almost unusable. Now 70mph in 5th and I am only running about 4400-4500rpm. I still get about 34mpg with a fuel additive(ethanol equalizer). Fully loaded with boss monkey and her luggage and I can still pull off with no problem.
Bill D.
 
Back
Top