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Discussion Starter · #1 ·
06 springer with performance machine master cylinder and calipers.
When I bought the bike I noticed that the rear brakes were pretty soft. Road it for a bit and wasn't happy with the soft rear brake. So I decided to bleed em. After countless hours of trying to bleed I decided that is order up a master cylinder rebuild kit. Installed it and still not building a firm pedal. The only way for me to get decent enough pressure is to put a hose on bleeder, fill the tube and slowly bleed all the air out once I get a little bit of pressure I close the bleeder. I tried to pump, hold, open bleeder and repeat with no luck. I've gotten to the point where I have enough pressure to have the rear brake light light up, but still really soft pedal an little to no rear brake. Kind of lost on what to do next. It has stainless brake lines and if I take the cap off the master cylinder and pump the pedal I don't see any air bubble in the reservoir.
Any suggestions on where to go next?
 

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I wish I had a bigger compressor I think it would work better.

Also check and see if the caliper looks real dirty inside. You may have to pull it off and and get the pistons more exposed but NOT all the way out of the bores , and spray them off with brake clean and scrub the area with a tooth brush, and spray it off again , spray the pads off too.

I pull the pads off and get some wooden door shims to put between the piston faces , once your done cleaning you can pound the shims together , adding more as you go to re-seat the pistons in the caliper.

Taking the rear caliper off is a PIA if it's the same as mine. Gotta pull the rear wheel because the axle go's through the caliper.

Make sure the pistons are moving in and out smoothly using the brake pedal before reassembly , keep some shims in to prevent them from popping out while doing this.
 

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Try bleeding the rear brake switch, bubbles of air can get trapped in the line at the switch. After that go to bleeding at the caliper.
 
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The Fighting Chicken
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I like bleeding my brakes using the syringe method.

Get a large syringe, I think 100cc, with a long rubber hose. Fill the syringe and hose with brake fluid, attach the hose to your bleeder valve. Loosen the valve and push fluid through the line until you don't see air bubbles in your brake fluid or your fluid comes out clean in the master cylinder.

A second syringe to suck the extra fluid from the master cylinder will be needed.

I got my syringes and hose from Tractor Supply Co. for a couple bucks.
 

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I like bleeding my brakes using the syringe method.

Get a large syringe, I think 100cc, with a long rubber hose. Fill the syringe and hose with brake fluid, attach the hose to your bleeder valve. Loosen the valve and push fluid through the line until you don't see air bubbles in your brake fluid or your fluid comes out clean in the master cylinder.

A second syringe to suck the extra fluid from the master cylinder will be needed.

I got my syringes and hose from Tractor Supply Co. for a couple bucks.
I do this on the front brakes , works pretty good :thumbsup
 

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Discussion Starter · #8 ·
Thanks, I'll give that a shot today. It's been driving me nuts not being able to bleed the brakes. I hate getting defeated by simple mechanical issues.
 

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The Fighting Chicken
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Thanks, I'll give that a shot today. It's been driving me nuts not being able to bleed the brakes. I hate getting defeated by simple mechanical issues.

Schmidty is a great mechanic and if he says to pull the switch off to check that I'd do that first, then bleed them again.

Good luck!
 

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go to a hardware store & buy a
1`qt. pumper oil can,
a automotive plastic vacuum "T"
about 8 ft. of plastic spegatti
drain resvior of brake fluid.
open your bleed valve on the disc & let it drain overnight.
you clean out the new can with MEK.
for dual disc, you use the "T"and cut it off at appopiate length
so you pump fresh brake fluid thru a short length of hose say 2'
to the bottom of the "T", the fluid then goes thru the schrader
valves into the caliper & up the OEM hard lines to the resivor.
stop pumping when you get it 1/2 full.
remove spagetti & give the brake lever 1 squeese then tighten bleed valve.
you can go to speedbleed.com & order valves for cars & bikes that have a check valve in the bleed screw.
hope this helps
i also use ATE super blue DOT 4 fluid it has a higher boiling piont
etc. i order on-line.
 

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Try bleeding the rear brake switch, bubbles of air can get trapped in the line at the switch. After that go to bleeding at the caliper.
I just replaced the pressure switch on my 04 XL1200 and went about bleeding the lines, seemed to work for a few then it stopped coming out now I have zero brakes. Can you please explain how you can bleed the switch itself? Didn't want to start a new thread so I replied to this one. Thanks.
 

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Hi. I'm new to Harley's. I noticed the comment....bleed at the rear brake switch. I know this probably sounds stupid...but where is the rear brake switch.....and how do you bleed there?

T.
 

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Hi guys. I’m new to this so I hope that I don’t step on any bodies toes but I have a problem. I have a 2005 Ultra Classic Moto trike conversion. I recently replaced the rear drum and shoe brake system with disc brakes. I had a hard time bleeding the rear brakes so I purchased new steel brakes lines, a new tee block and new flexible brake lines for the two calibers and the master cylinder. I’ve tried pressure bleeding, I’ve used one man bleeders (from Harbor Frieght) and Evan tried back bleeding. I still can’t get any brake peddle. I purchased a new master cylinder from Harley. That didn’t work so I then purchased a rebuild kit which didn’t work. Recently, I purchased a aftermarket master cylinder just to try to get some types of peddle. Nothing is working. Anyone have ant ideas.

Thanks
 

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trying to shove brake fluid in from both ends is going to leave a huge air pocket in the middle! Pick one direction and stick with it! Now that you have replaced every component of the brake system, obviously now it needs fluid.

If you are adding the fluid via the reverse bleed method: (from the calipers to the master cylinder)
Using a LARGE syringe: Do NOT use any vacuum to "pull fluid" This will create air pockets in the fluid. However, the vacuum is very handy to prevent overfilling the reservoir when pushing the air out of the lines.

1. Ensure the bleed ports are closed and the reservoir is open or uncapped.
2. Fill the syringe and servicing tube with brake fluid then place the tube onto the bleed port.
3. Crack open the bleed port.
4. While holding light pressure on the syringe plunger, slowly open the bleed valve, just enough that the plunger can be slowly pressed.
5. As the plunger gets near to the bottom of the syringe, CLOSE the bleed port to stop the flow of fluid.
6. ONLY AFTER the bleed port is CLOSED, remove the syringe to refill it by drawing fluid into it from the tube, DO NOT top fill it!
Allow get the air out of the tube and syringe before placing the tube back on the bleed port.
7. REPEAT 1 through 7 until the reservoir is 1/2 tp 3/4 full.
8. Now move to the 2nd caliper... This time use the master cylinder to apply the flow, while bleeding the air from the brake caliper. DO NOT ALLOW the Reservoir to draw in any air!
9. Repeat step 8 until resistance is obtained.
10. Install the cap on the reservoir. Slowly very slowly pump the brake until resistance is felt. Then service the reservoir to the full mark and close the cap.

At this point, prepare a way to apply brake pedal or hand lever (whichever applies) to hold NOT MASHED, just applied, overnite. This allows the mico bubbles to free up from the fluid and escape into the reservoir. Re verify fluid level before operating the vehicle.

The main idea here is DO NOT GET FRUSTRATED AND RUSH THIS... Brake lines are small. Fluid runs slow, take your time! Rushed brake jobs NEVER WORK!
 

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trying to shove brake fluid in from both ends is going to leave a huge air pocket in the middle! Pick one direction and stick with it! Now that you have replaced every component of the brake system, obviously now it needs fluid.

If you are adding the fluid via the reverse bleed method: (from the calipers to the master cylinder)
Using a LARGE syringe: Do NOT use any vacuum to "pull fluid" This will create air pockets in the fluid. However, the vacuum is very handy to prevent overfilling the reservoir when pushing the air out of the lines.

1. Ensure the bleed ports are closed and the reservoir is open or uncapped.
2. Fill the syringe and servicing tube with brake fluid then place the tube onto the bleed port.
3. Crack open the bleed port.
4. While holding light pressure on the syringe plunger, slowly open the bleed valve, just enough that the plunger can be slowly pressed.
5. As the plunger gets near to the bottom of the syringe, CLOSE the bleed port to stop the flow of fluid.
6. ONLY AFTER the bleed port is CLOSED, remove the syringe to refill it by drawing fluid into it from the tube, DO NOT top fill it!
Allow get the air out of the tube and syringe before placing the tube back on the bleed port.
7. REPEAT 1 through 7 until the reservoir is 1/2 tp 3/4 full.
8. Now move to the 2nd caliper... This time use the master cylinder to apply the flow, while bleeding the air from the brake caliper. DO NOT ALLOW the Reservoir to draw in any air!
9. Repeat step 8 until resistance is obtained.
10. Install the cap on the reservoir. Slowly very slowly pump the brake until resistance is felt. Then service the reservoir to the full mark and close the cap.

At this point, prepare a way to apply brake pedal or hand lever (whichever applies) to hold NOT MASHED, just applied, overnite. This allows the mico bubbles to free up from the fluid and escape into the reservoir. Re verify fluid level before operating the vehicle.

The main idea here is DO NOT GET FRUSTRATED AND RUSH THIS... Brake lines are small. Fluid runs slow, take your time! Rushed brake jobs NEVER WORK!
trying to shove brake fluid in from both ends is going to leave a huge air pocket in the middle! Pick one direction and stick with it! Now that you have replaced every component of the brake system, obviously now it needs fluid.

If you are adding the fluid via the reverse bleed method: (from the calipers to the master cylinder)
Using a LARGE syringe: Do NOT use any vacuum to "pull fluid" This will create air pockets in the fluid. However, the vacuum is very handy to prevent overfilling the reservoir when pushing the air out of the lines.

1. Ensure the bleed ports are closed and the reservoir is open or uncapped.
2. Fill the syringe and servicing tube with brake fluid then place the tube onto the bleed port.
3. Crack open the bleed port.
4. While holding light pressure on the syringe plunger, slowly open the bleed valve, just enough that the plunger can be slowly pressed.
5. As the plunger gets near to the bottom of the syringe, CLOSE the bleed port to stop the flow of fluid.
6. ONLY AFTER the bleed port is CLOSED, remove the syringe to refill it by drawing fluid into it from the tube, DO NOT top fill it!
Allow get the air out of the tube and syringe before placing the tube back on the bleed port.
7. REPEAT 1 through 7 until the reservoir is 1/2 tp 3/4 full.
8. Now move to the 2nd caliper... This time use the master cylinder to apply the flow, while bleeding the air from the brake caliper. DO NOT ALLOW the Reservoir to draw in any air!
9. Repeat step 8 until resistance is obtained.
10. Install the cap on the reservoir. Slowly very slowly pump the brake until resistance is felt. Then service the reservoir to the full mark and close the cap.

At this point, prepare a way to apply brake pedal or hand lever (whichever applies) to hold NOT MASHED, just applied, overnite. This allows the mico bubbles to free up from the fluid and escape into the reservoir. Re verify fluid level before operating the vehicle.

The main idea here is DO NOT GET FRUSTRATED AND RUSH THIS... Brake lines are small. Fluid runs slow, take your time! Rushed brake jobs NEVER WORK!

Thanks 1/2 Ton. I’ll try in the morning. I need to get the bike back on the road because as we all know, A happy wife makes a happy life.
 

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Thanks 1/2 Ton. I’ll try in the morning. I need to get the bike back on the road because as we all know, A happy wife makes a happy life.
Your better off playing with it tonight, so the bubbles can rise overnight. But who wants to spend a Saturday night wrenching, besides me? Right now, I have the fairing back off of my Ultra. Readjusting the bars. The Mrs is taking the Grandkids to her Mom's for a visit tomorrow. So if its not too muggy, just maybe i can sneak in a ride over the Ortegas (Hwy 74) for a lunch at Cooks Corner (A Cali famous Biker Bar). They make some KILLER Sammiches! And the Ocean Breeze flows up that canyon.
 
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This is a pieced together system, so there is a possibility that the bleeder is not at the highest point on the caliper depending on how it is mounted. If it isn't there will always be air above the bleeder screw. Remove the caliper, insert something between the brake pads so the pistons don't get popped out, tip the caliper so that the bleeder is at the top and bleed. Reinstall when all air is bled from the system.
 
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This is a pieced together system, so there is a possibility that the bleeder is not at the highest point on the caliper depending on how it is mounted. If it isn't there will always be air above the bleeder screw. Remove the caliper, insert something between the brake pads so the pistons don't get popped out, tip the caliper so that the bleeder is at the top and bleed. Reinstall when all air is bled from the system.
Thanks JLR. You are right. The passenger rear bleeder is not at the highest point, so I’ll take it off and turn it to the highest point, make sure that the brake pads are secure and bleed it then. Hope for the best.
 

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Let us know how it turns out.
 
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