Will '85 R80 Brembo caliper fit R65?

[Mucci]

Would the '85 R80 Brembo caliper fit the '83 R65?

They look identical however it doesn't appear part numbers match. Are they actually different?

R65 Caliper:



R80 Caliper:



I have the provisions to mount a right hand caliper on my R65 forks and I could use the extra braking power. I assume I'll need the master cylinder and brake lines off the R80 as well.

[Bob_Roller]

Possible bolt hole centers my not be correct for an R65 .

[mrclubike]

 I am not sure if the caliper you speak of is A F08 or a F09
I have a feeling it is a F09 48 mm piston 
I do know the Brembo F08 fits perfectly and is very cheap
When my ATE needed rebuilding I got a standard Brembo F08 from  MG Cycles    in Minnesota  instead of rebuilding it
http://www.mgcycle.com/index.php?main_page=product_info&cPath=110_115&products_id=1034
 
113.00 USD They are brand new and come with new pads  and is far cheaper to service so for me it was a no brainer
You have to remember the right side from the Guzzi fits the left side on the R65    

The only difference   the OEM BMW Brembo and the Moto Guzzi F08 is the Bore dia
The Original  ATE and Brembo  is 36mm(the reason is so pricey) and the MG F08 is 38mm so you are going to have more effective braking

[mrclubike]

I just noticed you are adding a second caliper
The single 38 mm stops more than  I need to

I would check the bore dia of you MC some one may have installed  a larger  one
a single rotor bike should have a 12 or 13mm
It is better to have the 12
I am running a 12mm MC and the 38mm F08 caliper

[mrclubike]

I do not think that is a R80 caliper in the second picture
If it was I think the mounting holes should be threaded

[mrclubike]

After more digging
Max shows the dual disc having 38mm pistons  and the single having the 48mm pistons so who knows

I know for a fact the 36mm and 38mm are interchangeable with no modification or spacing issue

[georgesgiralt]

Hello,
On the R65, the right hand caliper has different mounting holes diameter than the left hand side one.
It is for a special washer and associated tube to be mounted. These washer are made of different thicknesses and are used to center the caliper above the disc.
This way you can adjust the discs position by using washer under them and finish with the special washer on the right hand caliper.
If the dia is not correct, it is not a big deal to make it bigger...
Parts number 14 for the caliper and 16 for the discs.
Hope this helps.
P.S. there is not much clearance between the two fork legs so adjusting things properly is paramount.

[Tony Smith]

The the OP the answer to your question is "probably not".

If the R80 from which the caliper was taken is from a "post 1985 update" machine, i.e. a single rear shock machine then the caliper will NOT fit a twin shock R65.

The reason is the relative spacing of the wheel/fork set. The twin shock wheel spacing harks back to the days of spoked wheels, whereas the spacing on the monoshock machines is significantly narrower as it is based on the clearance requirements of the cast wheel.

The spacing is why you cannot simply buy a set of Brembos from an early K100 and use those (they can be had from wreckers as low as $AU60  a pair.

The monoshock airhead uses the same wheel spacing as the K100 and the brake calipers are identical.

Only two of three days ago as I fitted a K100 front end to my R65 I had the left caliper formt he R65 and K100 in my hands and the light finally dawned why you cannot interchange them.

[Tony Smith]

I had to dismount the newly fitted K100 Brembos today so I took the opportunity to snap a photo of the LHS K100 edition next to the one that I took off when removing the R65 front end.

Have a look at the RHS "distance" of each caliper. That is why you can't just bolt a K100 caliper to a twin-shock R65. As far as I know the monoshock twin-piston Brembos are the same dimensionally as the K100 calipers, although the piston diameter may vary.

[Matt Chapter]

Tony is correct, the twiin shock and monoshock brake calipers are not interchangeable.  In addition to the physical size and mount points, the brake pads are different as well.

[Mucci]

I realized I never updated this thread with my findings. In short, do they bolt up? Yes. Can you use them? No. Here’s why: https://advrider.com/f/threads/will-r80-brembo-caliper-fit-r65.1336869/#post-35827925