The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Milo_357 on September 27, 2011, 05:07:24 PM

Title: 1983(ish) R65LS Riders, can you help me out???
Post by: Milo_357 on September 27, 2011, 05:07:24 PM
Hey gang,

My efforts to transfer the dual front brakes from my 1983 R65LS to my 1982 R65 has run into a snag.

The lower fork sliders of the two bikes are exactly alike.  I mounted the second caliper with not problem.  Unfortunately, the brake discs do not seem to be lining up properly into both calipers when I mount to tire.  Looking at the wheel from the front of the bike, the left side brake disc does not fit into the left side caliper.

I have two of the shallow carrier discs on the wheel.  

The wheel IS the 19" snowflake, not the 18" from the R65LS.

The axle shafts are exactly the same between the two bikes.

R65LS riders.  Do you have extra spacers on your bikes? The wheel SEEMS to almost want one shallow and one deep carrier, but I know that is not right...

Is the 18" wheel a wider wheel???  IS this where I am failing?  How could it be wider though and use the same axle shaft...?

If anyone is willing to send me a photo of their front wheel from the front and side I'd appreciate it.  Or post it here better yet.

Any thoughts on what forest I am missing for the trees?

Thanks,

Dell
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Bob_Roller on September 27, 2011, 05:36:00 PM
The 19 inch wheel, is not for an R65, most likely for an R80 or R100, whether it will work or not on an R65, I don't know .

I've got two LS's and neither of them has any spacers between the rotor and wheel .
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Milo_357 on September 27, 2011, 06:36:01 PM
Quote
The 19 inch wheel, is not for an R65, most likely for an R80 or R100, whether it will work or not on an R65, I don't know .

I've got two LS's and neither of them has any spacers between the rotor and wheel .

Just another thing the PO did that is screwing me up!!!  >:(

Went and double checked.  It's definitely a 19 inch diameter wheel.  No wonder I've had problems with this conversion.  Argh!

Still, I wonder what is keeping me from having the proper width on my brake discs on the wheels...???
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Bob_Roller on September 27, 2011, 07:35:38 PM
I measured the front wheel on my '84 LS, forgot I have the rotors removed .

It measured 2.64 inches at the bolt holes, with one of Harbor Freight's 'finest' digital micrometer !!!!!!!!!!!!!!!
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Milo_357 on September 27, 2011, 08:01:46 PM
Quote
I measured the front wheel on my '84 LS, forgot I have the rotors removed .

It measured 2.64 inches at the bolt holes, with one of Harbor Freight's 'finest' digital micrometer !!!!!!!!!!!!!!!

Bob,

How long are the through bolts that hold your brake discs in place?  

Thanks!
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: tvrla on September 27, 2011, 08:07:50 PM
I've never measured the different dimensions of the different wheels - LS, R65 and R100 etc snowflakes. I'd imagine the snowflakes, whether 18" or 19" are the same at the hub. However, the shallow discs only work with the LS. The snowflake requires the deeper R65 rotor.

I'd imagine that a 19" snowflake will require the deeper R65 brake discs.

I also think there's enough room under the fender for the larger wheel and tire. I've seen it done and no modification were needed.
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Bob_Roller on September 27, 2011, 08:36:40 PM
There are different bolt lengths for the single disc I believe they are 70 mm, I want to say 90 or 100 mm for the dual disc setup.
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Bob_Roller on September 27, 2011, 08:42:36 PM
I finally found an 18 inch diameter front snowflake wheel from an '80 R65 I had in the garage, the hub thickness is 1.67 inches at the rotor bolt holes .

So a 'ballpark' figure of about 1 inch difference in thickness .

I don't know the dimension of a 19 inch wheel .
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Milo_357 on September 28, 2011, 06:21:25 AM
Quote
I finally found an 18 inch diameter front snowflake wheel from an '80 R65 I had in the garage, the hub thickness is 1.67 inches at the rotor bolt holes .

So a 'ballpark' figure of about 1 inch difference in thickness .

I don't know the dimension of a 19 inch wheel .

An inch difference between the 18 and 19 inch wheels?

Wow.  I had not idea.  That makes a lot of sense though. Like the IDIOT I am I got rid of the old 18 wheel before I was finished with what I was doing.  The through bolts from the R65LS wheel must be an inch or so longer than the originals from the R65 standard.

Now, the $64,000 question... Get an 18 wheel, or chuck the entire plan and sell eveything, and maybe get a 4 piston caliper to improve may braking performance?

Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Bob_Roller on September 28, 2011, 07:59:11 AM
I don't know what a 19 inch wheel thickness is, the 18 inch wheel has a thickness of 1.67 inches, a standard LS wheel has a thickness of 2.65 inches .

So there is a difference of about an inch between a standard 18 inch snowflake wheel and a standard LS wheel .

You need to measure your 19 inch wheel to see what dimension you get .
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Milo_357 on September 28, 2011, 08:26:11 AM
Quote
I've never measured the different dimensions of the different wheels - LS, R65 and R100 etc snowflakes. I'd imagine the snowflakes, whether 18" or 19" are the same at the hub. However, the shallow discs only work with the LS. The snowflake requires the deeper R65 rotor.

I'd imagine that a 19" snowflake will require the deeper R65 brake discs.

I also think there's enough room under the fender for the larger wheel and tire. I've seen it done and no modification were needed.

Oh, please don't tell me that I actually needed two of the DEEP dish carriers to pull off this conversion instead of two shallow dish... argh....
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: steve hawkins on September 28, 2011, 09:32:11 AM
Yep

Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Milo_357 on September 28, 2011, 10:43:29 AM
Quote
Yep


Would it REALLY work??? I mean, do you know if it was designed that way?
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Bob_Roller on September 28, 2011, 11:27:08 AM
You need to measure your 19 inch wheel and see what dimension you get for thickness .

I remember when I was replacing the OEM rotors on my '81 R65, I spent a lot of time researching the EBC catalog, part numbers for the rotors for the R100 bikes, which have 19 inch diameter snowflake wheels were different than the part numbers for the rotors for the R65 with the 18 inch snowflake wheels .

Did I mention you need to measure your 19 inch wheel, before you go any further !!!!!!!!!!!!!!!!!!!!!!!!
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Milo_357 on September 28, 2011, 12:59:40 PM
Quote
You need to measure your 19 inch wheel and see what dimension you get for thickness .

I remember when I was replacing the OEM rotors on my '81 R65, I spent a lot of time researching the EBC catalog, part numbers for the rotors for the R100 bikes, which have 19 inch diameter snowflake wheels were different than the part numbers for the rotors for the R65 with the 18 inch snowflake wheels .

Did I mention you need to measure your 19 inch wheel, before you go any further !!!!!!!!!!!!!!!!!!!!!!!!

Yes Sir!  ;D

You'd think, after living a life by the seat of my pants, I'd have learned such a lesson by now.   But nope.   Maybe some day...
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: tvrla on September 28, 2011, 10:28:00 PM
It's true, the bikes with 19" snowflakes use the shallow brake disc, while the R65 snowflakes take the deep one. And if the two snowflakes (18", 19") are the same thickness at the hub, then no matter which one you go with, you'll need the deep disc discs.

I don't know what the difference is, so don't ask me! Doesn't make any sense, but that's just the way it is. :)

I might have an 18" snowflake I'd sell. Nice and straight, but don't recall condition of the paint.
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: steve hawkins on September 29, 2011, 09:19:25 AM
Interestingly enough when I put wire wheels on my 1982 R100, I had to use R65 deep carriers for the disks.  I was then able to use the existing R100 fork spacing with the brembo brakes......

The wheel was a 19 incher 2 rib hub from a R80 ST, so the hub was slimmer variety as fitted to the R65......Spacers required on the Brembos......

Note: This has nothing to do with pre 81 ATE sliding caliper stuff though.
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: tvrla on September 29, 2011, 10:12:52 AM
Steve - Thanks for posting that! Those are unusual discs - I've never seen the deep dish solid like that - no holes. Are they stock BMW parts?
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: Milo_357 on September 29, 2011, 12:11:27 PM
Quote
It's true, the bikes with 19" snowflakes use the shallow brake disc, while the R65 snowflakes take the deep one. And if the two snowflakes (18", 19") are the same thickness at the hub, then no matter which one you go with, you'll need the deep disc discs.

I don't know what the difference is, so don't ask me! Doesn't make any sense, but that's just the way it is. :)

I might have an 18" snowflake I'd sell. Nice and straight, but don't recall condition of the paint.

Well, to show that I am fully vested in my "box of rocks" syndrome, I called the guy I bought the parts bike from to catch up with him (he'd been out of town), and told him the problems I was having.  His response?

"Did you check that extra 18" wheel that was in the parts boxs to see what the difference is?"

Que crickets...

Well, long story short, went home, tore apart garage, found said wheel, took off disc from 19" snowflake and held wheels side by side.

(No Bob, I haven't found my micrometer to measure yet!  :D  I WILL have a chance tonight!  ;))

Just eyeballing the two, it is obvious the 18" (what DO you call the non-snowflake, aluminum wheels?) is wider at the hub.  Guessimating 3/4 or so.

I'm gonna mount that sucker with a michelin I have & see what happens...  :o

I'll report back. Gotta find an inner tube that will fit & hoping theres one in town someplace.

Dell
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: tvrla on September 30, 2011, 12:31:37 AM
Quote
Just eyeballing the two, it is obvious the 18" (what DO you call the non-snowflake, aluminum wheels?) is wider at the hub.  Guessimating 3/4 or so.
Not sure how to answer that - there's the 18 and 19 inch snowflakes, the LS wheels, and the wire wheels. Are you asking about the LS wheels (non snowflakes)?

It makes sense the LS wheels are wider than the snowflake since the LS takes the shallow discs where the snowflake takes the deep.
Title: Re: 1983(ish) R65LS Riders, can you help me out???
Post by: steve hawkins on September 30, 2011, 02:41:08 AM
The discs are not BMW items.  They are pfm cast iron discs.  

They were originally fitted to a set of shallow carriers when I had the standard snow flake on the bike.  

I had a set of Grimeca R65 discs that had warped on my R65 Cafe Racer, so I nicked those deep dish carriers for this setup.  

I have a single EBC disc on ther Cafe Racer now.....cos I am cheap.... ;)

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