I have a 06 Heritage. I put new wheels & floating brake rotors on about 1500 miles ago. When the rotors had about 1000 miles on them I added a 6 piston HHI front brake caliper. I used the correct spacers to center the caliper over the front rotor. I then back bled the brakes. The instructions stated to ride about 200 miles of town riding to allow the pads to properly seat. I have put about 400 miles of town riding on them.

When I first put them on I noticed the brake lever got hard immediately but didn't provide a lot of stopping power (maybe half that of the old HD caliper). I didn't get on them hard & kept using them for the 200 mile in-town break in period. They didn't get much better. I took the top off the master cylinder insuring all the brake lines were running uphill. I tapped on the caliper & fittings while squeezing & releasing the brake lever. I did notice one air bubble but that was all. I then took it for a test ride getting on the front brake hard at 40 to 45 mph. The lever doesn't feel quiet as hard but you have to get on the lever very hard to make an emergency stop. I couldn't lock the front wheel if my life depended on it (I don't want to lock it but I do want it to stop quickly). It stopped better with the old HD caliper. I hope I am overlooking something.

Any advice will be appreciated. Thanks

 

Bump..

 

I wonder if your master cylinder pushes enough fluid for the new calipers?

 

If your stock front brake caliper was a four piston and you switched to a six piston caliper, I would change out the master cylinder .. I had to when I went from a four to six piston caliper.