Need help please ..... 83 cafe build speedometer install from r68

Have 1983 R100RT, Buying a r68 Speedo to install in a slash 2 bucket. My question and help I need please

1. What is my driveline ratio on my 83 R100RT please anyone know ?

2. the R68 speedo - veigel 0-180 kph W=.95 35/9 final drive R6, this speedo will only read accurately with a 35/9 final drive. That is a ratio of 3.8888
(That is quite a bit different that 2.9 and it will be wildly inaccurate.)


3. Is there anyone in the Toronto Canada area that can help with this?

From one website, the final drive ratio on an '83 R100RT is either 3.00 (33/11) or 2.91 (32/11). The speedometer ratios that would normally go with those are 0.691 (in kilometers) or 0.67. Not sure how you can cobble something like that together. I think you'll need final drives from the R45 but there will still be some problems.

In so much as BMW motorcycle speedometers are not terribly accurate, Just hook it up and learn to read the offset.

James.A said:

In so much as BMW motorcycle speedometers are not terribly accurate, Just hook it up and learn to read the offset.

Click to expand...

best idea ever ? LOL thanks

But I do want it somewhat accurate at minimum sir

The least costly solution is likely to be just having the speedo recalibrated by one of the well-known instrument shops. The shop will likely want you to provide a cable rotation number, which involves clipping a partially unwound paper clip to the end of the speedo cable, then with tires properly inflated and loaded pushing the bike through one exact full rotation of the rear wheel (as marked on ground and tire). You’ll be asked to record the number of rotations of the paper clip over that distance, down to the fraction or percentage on the last rotation. With that info the speedo shop can recalibrate the speedo to dead-on at a given speed, usually 60mph.

I had to go through this procedure a couple of decades ago with my R80ST, and it ended up being the most accurate speedo I’ve ever had on a bike.

Best,
DG

20774 said:

From one website, the final drive ratio on an '83 R100RT is either 3.00 (33/11) or 2.91 (32/11). The speedometer ratios that would normally go with those are 0.691 (in kilometers) or 0.67. Not sure how you can cobble something like that together. I think you'll need final drives from the R45 but there will still be some problems.

Click to expand...

Thank you very much sir

Robbie

Speedo issue

Need your help if you do live in this area.

http://www.foreignspeedoinc.com/contact

Fermont at Foreign Speed needs to just run a quick speedo test on you bike ( 52 feet of rolling the bike along to see the amount of turns in your speedo cable ) 30 minutes of your day, I will pay you for your time. Reason for ask is I am sending him my r68 speedo from Toronto Canada and he needs a quick test to read amount of times speedo cable goes around and calibrate it for my 83 R100RT.


Address:
Foreign Speedo Inc.
2246 1/2 University Ave.
San Diego, CA. 92104

Phone:
(619) 298-5278


If there is anyone out there kind enough to give me a hand I would be extremely grateful. Please private message me

Robbie