R65LS Final drive

Discuss all things 1970 & later Airheads right here.
MotoD
Posts: 29
Joined: Sat Dec 04, 2021 12:26 pm

R65LS Final drive

Post by MotoD »

Hey all! I just wrapped up a 1982 R65LS with a 860 big bore. I love the get up and go but the gearing is a bit short. It currently has a 32/9 final drive. Ive got the double shock swing arm and drum brakes so would like to get something that'll mate up. Do any of you have an opinion on what ratio I should look for? Thinking something off an R80 or so...possibly 32/10 or 11. Thanks as always!!
MDG1.jpg
MDG1.jpg (1.82 MiB) Viewed 998 times
Attachments
MDG2.jpg
MDG2.jpg (1.93 MiB) Viewed 999 times
User avatar
gspd
Posts: 1041
Joined: Tue Aug 03, 2010 8:04 pm

Re: R65LS Final drive

Post by gspd »

:o
I was waiting for someone to chime in but everyone seems at a loss for words.
So here's my 2 cents...
Fitting a larger diameter rear tire would be the easiest way resolve your gearing issue.
(You might have to relocate the petcocks.)
Attachments
images.jpg
images.jpg (13.42 KiB) Viewed 951 times
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
MotoD
Posts: 29
Joined: Sat Dec 04, 2021 12:26 pm

Re: R65LS Final drive

Post by MotoD »

gspd wrote: Tue Sep 13, 2022 2:42 am :o
I was waiting for someone to chime in but everyone seems at a loss for words.
So here's my 2 cents...
Fitting a larger diameter rear tire would be the easiest way resolve your gearing issue.
(You might have to relocate the petcocks.)
Yeah…good stuff. Don’t want to change tires so I’ll figure it out. Thanks anyways
Rob Frankham
Posts: 1214
Joined: Thu Aug 26, 2010 2:11 pm
Location: Scotland UK, 20 miles from civilisation up a dead end road!
Contact:

Re: R65LS Final drive

Post by Rob Frankham »

I would guess that a 32/11 would be too high for you, you'd trade too much of the 'get up and go' for top speed which probably wouldn't be too comfortable on a bike with zero protection. I would suggest that a 32/10 or a 34/11 would be more in keeping... but the only way to really know would be to do it and make your own decision. Incidentally, I would expect a R65LS to have a 31/9 rather than a 32/9... but then, you don't say that the current drive is original I suppose.

Assuming the current drive is a stock twinshock drive, any unit, smooth cased or stepped cased, from a twinshock is going to bolt up to the swong arm but you might have issues with the brake. Not sure quite what the differences are... the cam seems to be common to other models but the brake shoes are unique to the R65LS.

Rob
ImageImageImage
barryh
Posts: 730
Joined: Fri Oct 01, 2010 12:30 pm

Re: R65LS Final drive

Post by barryh »

R65LS brake shoes are unique to the R65LS wheel being both wider and larger in diameter. As long as you keep the same rear wheel you will need to retain them. I don't know if the wider shoes means the same cam spindle or not but you would be able to transfer the old one if it's an issue.
barry
Cheshire
England
MotoD
Posts: 29
Joined: Sat Dec 04, 2021 12:26 pm

Re: R65LS Final drive

Post by MotoD »

Thanks for all the tips. I have a standard R65 in the shop as well also with the stock 32/9 final drive. It has the snowflake wheels VS the LS style wheels. I’ll try next week to pull both wheels and see if the stock 65 rear wheel fits ok onto the Ls setup. The final drives look identical but I’ll be interested to see and measure the brake setups. Thanks again.
MotoD
Posts: 29
Joined: Sat Dec 04, 2021 12:26 pm

Re: R65LS Final drive

Post by MotoD »

barryh wrote: Wed Sep 14, 2022 11:28 am R65LS brake shoes are unique to the R65LS wheel being both wider and larger in diameter. As long as you keep the same rear wheel you will need to retain them. I don't know if the wider shoes means the same cam spindle or not but you would be able to transfer the old one if it's an issue.
So are you saying I may be able to transfer over some of the LS bits to the possible donor drive? I found a good deal on a 32/10 setup from an R90s. The shoes maybe able to be swapped over which would be fantastic, I wouldn't be surprised if the cam spindle is the same across the board BUT could be wrong here...
MotoD
Posts: 29
Joined: Sat Dec 04, 2021 12:26 pm

Re: R65LS Final drive

Post by MotoD »

Quick look @ calmoto parts fiche part number: 35211454836 for the rear brake shoe cam appears to be shared by most airheads including the R90s so that is a good sign. The LS also uses a 200x25mm rear brake shoe which does a lot of other years/models so once I get this all sorted I will report back with my findings!

https://bmwparts.calmoto.com/p/bmw__R65 ... 54836.html
Seth
Posts: 275
Joined: Thu Aug 12, 2010 4:45 pm

Re: R65LS Final drive

Post by Seth »

MotoD
Posts: 29
Joined: Sat Dec 04, 2021 12:26 pm

Re: R65LS Final drive

Post by MotoD »

Seth wrote: Thu Sep 15, 2022 10:19 pm I thought all R90S had 33/11

https://bmwmotorcycletech.info/ringgears.htm
🤷 this is what one of the eBay listings I’m watching states

https://www.ebay.com/itm/234681069513?m ... media=COPY
Post Reply