New Brake Issue
Whether the bike is cold or hot rear brake behaves the same.
At highway speed I have to pump the brake. If I use the front brake without touch the rear and slow down to 10 mph before touching the rear brake it will work perfect. As I accelerate back to 40 mph + it startes getting soft and by the time I get up to 60+ I have to pump it again.
My gut feeling tells me to follow up on what Twizted Biker and AngrySailor are thinking. I will investigate that and report what I find.
As far as fluid, both front and rear brakes were 100% rebuilt. Calipers were the only parts NOT replaced, but completely rebuilt and cleaned in the process. Cleaning consisted of stripping down the calipers and washing with hot soapy water and a soft tooth brush. Then wiping/air drying, then wiping down inside with acetone and Q-tips, again blow drying with compressed air. I'm very **** about my brakes. Been that way since a childhood experience on a '69 Honda CL350.
At highway speed I have to pump the brake. If I use the front brake without touch the rear and slow down to 10 mph before touching the rear brake it will work perfect. As I accelerate back to 40 mph + it startes getting soft and by the time I get up to 60+ I have to pump it again.
My gut feeling tells me to follow up on what Twizted Biker and AngrySailor are thinking. I will investigate that and report what I find.
As far as fluid, both front and rear brakes were 100% rebuilt. Calipers were the only parts NOT replaced, but completely rebuilt and cleaned in the process. Cleaning consisted of stripping down the calipers and washing with hot soapy water and a soft tooth brush. Then wiping/air drying, then wiping down inside with acetone and Q-tips, again blow drying with compressed air. I'm very **** about my brakes. Been that way since a childhood experience on a '69 Honda CL350.
Club Member
Joined: Mar 2009
Posts: 66,110
Likes: 51,396
From: Niles Canyon Ca.
Whether the bike is cold or hot rear brake behaves the same.
At highway speed I have to pump the brake. If I use the front brake without touch the rear and slow down to 10 mph before touching the rear brake it will work perfect. As I accelerate back to 40 mph + it startes getting soft and by the time I get up to 60+ I have to pump it again.
My gut feeling tells me to follow up on what Twizted Biker and AngrySailor are thinking. I will investigate that and report what I find.
As far as fluid, both front and rear brakes were 100% rebuilt. Calipers were the only parts NOT replaced, but completely rebuilt and cleaned in the process. Cleaning consisted of stripping down the calipers and washing with hot soapy water and a soft tooth brush. Then wiping/air drying, then wiping down inside with acetone and Q-tips, again blow drying with compressed air. I'm very **** about my brakes. Been that way since a childhood experience on a '69 Honda CL350.
At highway speed I have to pump the brake. If I use the front brake without touch the rear and slow down to 10 mph before touching the rear brake it will work perfect. As I accelerate back to 40 mph + it startes getting soft and by the time I get up to 60+ I have to pump it again.
My gut feeling tells me to follow up on what Twizted Biker and AngrySailor are thinking. I will investigate that and report what I find.
As far as fluid, both front and rear brakes were 100% rebuilt. Calipers were the only parts NOT replaced, but completely rebuilt and cleaned in the process. Cleaning consisted of stripping down the calipers and washing with hot soapy water and a soft tooth brush. Then wiping/air drying, then wiping down inside with acetone and Q-tips, again blow drying with compressed air. I'm very **** about my brakes. Been that way since a childhood experience on a '69 Honda CL350.
Club Member
Joined: Mar 2009
Posts: 66,110
Likes: 51,396
From: Niles Canyon Ca.
Ok, the big banana caliper with the two pin mount that we all put the spring under to stop the rattling ? If so when the mount holes wobble out that caliper ***** to one side and the pads wear funny and rattle. You'll dick with it and the pedals great, go a good ride with steady highway and bam no rear brakes all of a sudden or you have to pump them to get something.
Hit the pedal and watch the caliper, it moves any you've found the biggest contributor to your issue.
Hit the pedal and watch the caliper, it moves any you've found the biggest contributor to your issue.
Rear disc is not warped, so I can eliminate that.
Brake fluid seems a little murky for only having between 3k and 4k miles. Did seem a little low so I added some. DOT5 used when brakes were re-assembled after cleaned and rebuilt.
There is just over 1" between the MC and the front header. Having trouble believing this is close enough for the heat to effect the MC while at highway speed, but I'm trying to keep an open mind. I double checked the brake line all the way back to the caliper to make sure it doesn't come close to the exhaust. It's tucked (and zip tied) on the other side of the frame tube to keep it away from the exhaust.
Brake fluid seems a little murky for only having between 3k and 4k miles. Did seem a little low so I added some. DOT5 used when brakes were re-assembled after cleaned and rebuilt.
There is just over 1" between the MC and the front header. Having trouble believing this is close enough for the heat to effect the MC while at highway speed, but I'm trying to keep an open mind. I double checked the brake line all the way back to the caliper to make sure it doesn't come close to the exhaust. It's tucked (and zip tied) on the other side of the frame tube to keep it away from the exhaust.
Stellar HDF Member
Joined: May 2018
Posts: 2,170
Likes: 435
From: australia
new master cyclinder. a hd mech once told me there a throw away part .he was right fixed my problem
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Yep, almost there. These forward controls have always been a little difficult. Luckily the previous owner kept the originals, I just need to replace the MC as it's a ball of rust at this point. I don't want to spend too much money right now as I'm saving up to send my transmission to johnjzjz this winter ( if the storms haven't washed him away )