The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: NorR65 on September 13, 2017, 11:17:33 AM

Title: From dual ATE to single Brembo 38 mm
Post by: NorR65 on September 13, 2017, 11:17:33 AM

Hello. My R65 from 1981 has twin ATE calipers and 16 mm mastercylinder. The caliper pistons i rusty. I wish to replace the ATE calipers with one Brembo 38mm caliper and 12 mm mastercylinder. Can I choose which side I mount the Brembo caliper? All single disc R45 and R65 have disc and caliper on left side. Thanks

Title: Re: From dual ATE to single Brembo 38 mm
Post by: Barry on September 13, 2017, 12:09:30 PM

Good question.  While the vast majority of single disc airheads had the disc on the left the R80 GS and the R80 ST had it on the right.  I can't think of why it would make a difference.

Title: Re: From dual ATE to single Brembo 38 mm
Post by: mrclubike on September 13, 2017, 08:52:00 PM

I cant think of any reason either side will not work
Just need the correct caliper

Just remember that what side the caliper works on is also dependent if it is above or below the fork

Example the same caliper works on the left bottom or right top

Smart move going with the Brembo F08 38mm  caliper  and 12mm MC
That is what I did and it works great

I   replaced the original hose also
It was braking down and turning the fluid black
The brake lever got a lot firmer also

Title: Re: From dual ATE to single Brembo 38 mm
Post by: Tony Smith on September 14, 2017, 01:48:13 AM

Quote

Good question.  While the vast majority of single disc airheads had the disc on the left the R80 GS and the R80 ST had it on the right.  I can't think of why it would make a difference.

Depends on whether the caliper is fore or aft of the leg

Title: Re: From dual ATE to single Brembo 38 mm
Post by: Barry on September 14, 2017, 12:33:42 PM

Quote

depends on whether the caliper is fore or aft of the leg

I did wonder if that was the reason but the R80ST and R80G/S were both aft of the leg just like an R65

Title: Re: From dual ATE to single Brembo 38 mm
Post by: Tony Smith on September 14, 2017, 05:26:25 PM

Quote

Quote

depends on whether the caliper is fore or aft of the leg

I did wonder if that was the reason but the R80ST and R80G/S were both aft of the leg just like an R65

OK, the Brembo FO8 calipers were "invented' at the behest of Ducati and where fitted to the front of the forks. Hence the "left" or "right" handedness relates to their original fittment.

In our case we have a "right" caliper fitted behind the fork to the left side, and a "left" caliper fitted behind the right hand side fork leg.

This has caused ongoing confusion for as long as FO8s have been around.

Title: Re: From dual ATE to single Brembo 38 mm
Post by: NorR65 on September 15, 2017, 12:03:53 PM

Thanks
I hope I get new Brembo caliper and mastercylinder before spring 2018. We will see.