HarleyTechTalk

Technical Forums => General => Topic started by: WhipLash96 on June 09, 2021, 01:35:38 PM

Title: 99-07 Rear Brake Master Cylinder vs. 08 and Up Rear Master
Post by: WhipLash96 on June 09, 2021, 01:35:38 PM
I just scored a good deal on a new braking system for my 01 Road Glide. In the deal I got a new Brembo rear caliper. I have heard that when making the conversion that the rear master cylinder needs to be upgraded? What is the difference between the stock MC and the supposed upgraded one?

Thanks!
Title: Re: 99-07 Rear Brake Master Cylinder vs. 08 and Up Rear Master
Post by: klammer76 on June 09, 2021, 09:20:31 PM
 Bore size
Title: Re: 99-07 Rear Brake Master Cylinder vs. 08 and Up Rear Master
Post by: road-dawgs1 on June 10, 2021, 03:22:03 AM
I believe the newer rear masters are made of plastic as well aren't they? They appear that way anyhow.
Title: Re: 99-07 Rear Brake Master Cylinder vs. 08 and Up Rear Master
Post by: WhipLash96 on June 10, 2021, 03:30:05 AM
Yes, they are made of plastic for the 08 and up and I subsequently found out the 08 and up master's mount differently than 99-07's. Harley revised the 99-07 master's which ends in 99F. Anyone know what that revision was?
Title: Re: 99-07 Rear Brake Master Cylinder vs. 08 and Up Rear Master
Post by: klammer76 on June 10, 2021, 08:38:50 AM
Rear Brembo MC is 5/8" bore. Stock Kelsey Hayes is 11/16" bore. On my 2002, I initially used the Kelsey Hayes mc and never got the feel and power to the brake that I thought it should have. Cut the mount for the OE mc off the frame and fitted up the 2008 oem mc for the brembo set up. Works well and way easier to remove the rear wheel/tire. Stock Kelsey Hayes can be reinstalled if a mount from early triglide is sourced. I initially used an EBC rear rotor with harley pads (sintered). Hard on that rotor. Switched back to a late model oem rotor with EBC HH sintered pads and have very good brake. EBC EP pads would give even more bite.

To do the rear correctly, the following needs to be done:
-Brembo anchor need to be honed to accept the 1" axle (from 25mm)
-2008 right side non abs axle spacer needs to be honed for 1" axle and machined to 0.710
-2008 non abs rear brake line
-2008 and later rotor
-2008 up mc

To get the best performance from the fronts, the correct brembo mc should also be used, again, different bore size. Others here have used the older, kelsey hayes mc's and are satisfied with them. I never liked the way they felt.

I also used dot 5 (after complete disassembly of the Brembo calipers and master cylenders and cleaned with denatured alcohol and electrical cleaner). Others have done the same. If I was doing it all again I would consider staying with dot 4 but I go back and forth. I use Harley floating rotors on the front with EBC EPHH pads. Bike stops on a dime. I initially used the oem, 2008 rotors but they didn't hold up.

I detailed the removal of the rear mc mount here on htt after getting questions about it.
Title: Re: 99-07 Rear Brake Master Cylinder vs. 08 and Up Rear Master
Post by: WhipLash96 on June 18, 2021, 06:43:35 AM
Quote from: klammer76 on June 10, 2021, 08:38:50 AM
Rear Brembo MC is 5/8" bore. Stock Kelsey Hayes is 11/16" bore. On my 2002, I initially used the Kelsey Hayes mc and never got the feel and power to the brake that I thought it should have. Cut the mount for the OE mc off the frame and fitted up the 2008 oem mc for the brembo set up. Works well and way easier to remove the rear wheel/tire. Stock Kelsey Hayes can be reinstalled if a mount from early triglide is sourced. I initially used an EBC rear rotor with harley pads (sintered). Hard on that rotor. Switched back to a late model oem rotor with EBC HH sintered pads and have very good brake. EBC EP pads would give even more bite.

To do the rear correctly, the following needs to be done:
-Brembo anchor need to be honed to accept the 1" axle (from 25mm)
-2008 right side non abs axle spacer needs to be honed for 1" axle and machined to 0.710
-2008 non abs rear brake line
-2008 and later rotor
-2008 up mc

To get the best performance from the fronts, the correct brembo mc should also be used, again, different bore size. Others here have used the older, kelsey hayes mc's and are satisfied with them. I never liked the way they felt.

I also used dot 5 (after complete disassembly of the Brembo calipers and master cylenders and cleaned with denatured alcohol and electrical cleaner). Others have done the same. If I was doing it all again I would consider staying with dot 4 but I go back and forth. I use Harley floating rotors on the front with EBC EPHH pads. Bike stops on a dime. I initially used the oem, 2008 rotors but they didn't hold up.

I detailed the removal of the rear mc mount here on htt after getting questions about it.

Ok thanks. That answered a couple of other questions.