Motorcycle Repair: Front brake dragging, honda cb400t, cylinder body

Question
Hi Bill,

     I bought a 1981 honda cb400t Hawk not that long ago and haven't been able to get the front brake working right. The caliper won't release all the way which causes the brake to drag. So far I have put a new caliper on and changed the brake fluid but that still didn't solve the problem. If you could give me any input at all I would really appreciate it.
                             Thanks Alot...JIM

Answer
Jim, if you put a new caliper on and the mounting system is all okay, then you have a blocked bleed port in the master cylinder... not surprising after 23 years.

Remove the master cylinder and clean the reservoir especially at the bottom where all the crud collects. Towards the front of the cylinder (hose end) you should see two ports that supply fluid the the cylinder and the forward one is to bleed back the trapped fluid when the plunger is released. I would really recommend disassembly of the master cylinder, installing a fresh kit after you have inspected and cleaned the old cylinder body thoroughly.

The caliper mount should have some sliding pins that allow the caliper to center itself over the disc. Be sure that it can move back and forth, as a final check.

Bill Silver