Weak front brake

[xs650newb]

Hey guys,

I've installed a new SS brake line on my new to me 1977 XS650.

I bled the brakes and the lever action feels pretty good. It is solid and I can't squeeze the lever so that it touches the handlebar. I've compared it to my other XS650 which has a real great front brake action and they feel quite similar.

Anyways, I feel like my front brake isn't working as it should. when I go for a ride my stopping power is not that great (as compared to my other XS).

I have new brake pads in the caliper. Was I supposed to do something to those pads before I installed them? Roughen them up or something? Also, I've spilled brake fluid and oil onto the rotor a few times. I wiped it off with a paper towel but I'm sure there is still residue. Is there anything I can do to clean the rotor? Would carburetor spray work?

Best,
Adam

 

[jd750ace]

Did you disassemble and thoroughly clean the caliper? If it's not got all the gunk cleaned out from behind the seal groove, it don't work so well.

 

[xs650newb]

I did clean out the caliper. Might try it again because it probably got dirty when I first was bleeding the brakes with the old, very dirty brake lines.


Anyways, was I supposed to prep the pads before installation in any way? Roughen them up or something? Also, any good ways to clean the rotor because I definitely had some brake fluid on there.

Best,
Adam

 

[jd750ace]

You can clean the rotor with alcohol. As far as pad prep, no. The disc, I used a dual action (or random orbit) sander with some 120 grit to clean up the swept area of the disc. I also drilled ir, but not related. I have the standard 79 Special front caliper with SS 3/32 line and an 11mm master (Brembo) from a mid 90s Moto Guzzi and my front brake easily overwhelms the fork and frame. Fantastic feel and all the braking power it'll stand for now. Maybe after I get some worthy suspension under it they won't be as great to me but for now 2 finger braking works great.

 

[5twins]

What new brake pads are you using? I went with the Ferodo Platinums from 650Central because they were highly recommended and honestly, I don't care for them. The original stock pads stopped better. I will be re-installing them.

 

[angus67]

sounds like your pads are contaminated with brake fluid. They still work, it just somehow don't feel rite? I droped my bike off the lift, and it landed rite on the brake lever first, forcing fluid past the piston, on to the pads. I rebuilt the caliper afterward, and re-bled, but just somehow feels different. Just get the stock replacements.

 

[xs650newb]

Hey guys,

All good advice. Thanks.

By the way, the pads are from mikesxs.

So here is what it sounds like I should do.


Rotor: Lightly sand with high grit sandpaper.
Pads: Nothing can be done.

 

[XSLeo]

I use brake cleaner, comes in a spray can. It will clean the crud off the rotor and pads. If the pads are to soaked in fluid they won't come completely clean but should improve.
Leo

 

[jd750ace]

the pads are from mikesxs.

Oh.