R1100 - Changing Gear Ratios

[Jim Moore]

Hi Guys,

 

My R1100 redlines (8K rpm) in second at about 72 mph. Unfortunately that's right where I'm about halfway through the exit of most of my favorite corners. I've tried 3rd gear, but that brings me down to about 6K rpm in the corners, which feels too sluggish. What I really need is for 2nd gear to redline at about 80 mph. In the (not entirely unlikely) event that I ever have the tranny out again, is there something I can change in the gearbox to accomplish that? Can I do something with the gearing in the final drive?

 

Thanks,

[dirtrider]

41 minutes ago, Jim Moore said:

Hi Guys,

 

My R1100 redlines (8K rpm) in second at about 72 mph. Unfortunately that's right where I'm about halfway through the exit of most of my favorite corners. I've tried 3rd gear, but that brings me down to about 6K rpm in the corners, which feels too sluggish. What I really need is for 2nd gear to redline at about 80 mph. In the (not entirely unlikely) event that I ever have the tranny out again, is there something I can change in the gearbox to accomplish that? Can I do something with the gearing in the final drive?

 

Thanks,

 

 

Morning Jim that is a difficult thing to answer without a lot of research.

 

Does your 1100S  have ABS brakes as that can change things.

 

I don't know how accurate my gear ratio chart is on the 1100S bike as those things are very difficult to pin down (my chart shows 33/12 so that would be 2.75 ratio).  Look on your final drive near the top vent to see if is stamped 33/12? If it's not 33/12 then you might be able to improve 2nd gear.

 

About the only way to go on final drive gearing is up  2.81 or 2.91 & that is directionally wrong to help your 2nd gear issue but could bring 3rd into use but that could ruin the higher gear usage for other corners.

 

Ideally you would like to only address 2nd gear but I don't have an 'S' bike trans gear ratio chart (maybe Try Anton as he might have, or know of,  the gearing that you need for 2nd.

 

[Jim Moore]

HI DR,

 

Sorry, it's an R1100RS. I totally forgot about the bikes in my sig line. Does that change anything?

[dirtrider]

30 minutes ago, Jim Moore said:

HI DR,

 

Sorry, it's an R1100RS. I totally forgot about the bikes in my sig line. Does that change anything?

 

Afternoon Jim

 

It might change things as the RS should have a 31/11 (2.81) ratio, the 1100 S  33/12 (2.75) would raise your 2nd gear speed slightly but would also raise the other gear ratios as well. (the positive effect on 2nd gear might be offset by negative traits in the other gear ranges)

 

The problem is: I'm not sure if the 1100S final drive would work as I don't know if the 1100S final drive would allow your RS ABS  wheel speed sensor to mount & work. The gear set should fit your housing (I think but can't even be positive on this).

 

You have one of those problems that will either take someone that been-there & done-that, or take a lot of research to find what will fit & give you the positive changes that you want without having a negative impact in other gear ranges.

 

Another option is to maybe use a real early RS final drive as I believe that is 34/11 (3.09) then try to figure if that will lower 3rd enough to get what you need (again that would also effect the other gear ranges)-  Like possibly give you a creeper 1st gear (or a wheel standing devil in 1st gear).

 

I do believe my first move would be to call Anton  as maybe he has addressed something similar before (at least that would be my starting point anyhow)