Bleeding brakes on Fat Boy
Intermediate
Joined: Mar 2013
Posts: 25
Likes: 0
From: wesley chapel fl
Stellar HDF Member
Joined: Nov 2012
Posts: 2,620
Likes: 1,091
From: Eastern IA
Speed bleeders are great if the system is full, if you replaced a line or caliper you need to flush fluid through so there's little to no air before speed bleeders work well or work at all.
I just went through this most hated job ,flushing the lines, tried the Mityvac , tried reverse bleeding , speed bleeders ,couldn't get a good lever no matter what.
Finally realized that my (front ) caliper pistons weren't getting full travel or hanging up. My bike is low mile and it sat alot before I got it. Pulled the caliper and sprayed it down with brake clean, scrubed around the pistons w/ toothbrush. I compressed them then pumped em back up until they started moving nice. Then I finally started getting some lever.
I picked up one of those pneumatic style bleeders from HF for $25 , works good and is better quality than you might expect. I also zip tied my lever back for 24hrs when I was done flushing , that does make a difference. Now it's rock solid with an inch or less travel.
I just went through this most hated job ,flushing the lines, tried the Mityvac , tried reverse bleeding , speed bleeders ,couldn't get a good lever no matter what.
Finally realized that my (front ) caliper pistons weren't getting full travel or hanging up. My bike is low mile and it sat alot before I got it. Pulled the caliper and sprayed it down with brake clean, scrubed around the pistons w/ toothbrush. I compressed them then pumped em back up until they started moving nice. Then I finally started getting some lever.
I picked up one of those pneumatic style bleeders from HF for $25 , works good and is better quality than you might expect. I also zip tied my lever back for 24hrs when I was done flushing , that does make a difference. Now it's rock solid with an inch or less travel.
Stellar HDF Member
Joined: Mar 2006
Posts: 2,395
Likes: 153
From: Utah
When you evacuate the system, power bleeding works but it can be a messy proposition. The best approach with power bleeding, in my opinion, is to fill the system from the caliper which forces the air up to the master cylinder. The problem is that you have to be very careful with the fluid that is filling the master cylinder or you will end up with a rat bike paint job on your bike.
I think that a good compromise is to pump the lever for as long as you can get air to rise up in the master cylinder, then bleed the caliper until no air comes out of the bleeder screw. Put the master cylinder lid on without screwing it down and let the bike sit over night. Repeat the same process. This should get you some brake. Reinstall the cover and go for a ride (reasonably long) and let the bike sit over night again. This will accumulate all of the little bubbles into bigger ones. Repeat the same bleeding process with your lid removed. Make sure you always keep an eye on the fluid level. This should get you a good lever. You can repeat the process one more time if the lever seems a little spongy. There is no silver bullet to getting air out of an evacuated motor cycle brake system I don't think. On a car a power bleeding (pushing or vacuuming) works great but you don't have to worry about the mess so much.
Just my buck fifty.
C#
I think that a good compromise is to pump the lever for as long as you can get air to rise up in the master cylinder, then bleed the caliper until no air comes out of the bleeder screw. Put the master cylinder lid on without screwing it down and let the bike sit over night. Repeat the same process. This should get you some brake. Reinstall the cover and go for a ride (reasonably long) and let the bike sit over night again. This will accumulate all of the little bubbles into bigger ones. Repeat the same bleeding process with your lid removed. Make sure you always keep an eye on the fluid level. This should get you a good lever. You can repeat the process one more time if the lever seems a little spongy. There is no silver bullet to getting air out of an evacuated motor cycle brake system I don't think. On a car a power bleeding (pushing or vacuuming) works great but you don't have to worry about the mess so much.
Just my buck fifty.
C#
Thread
Thread Starter
Forum
Replies
Last Post
