Brake troubles continued.

Hi all,

A few weeks ago I posted about not getting a full brake lever.

It all started over a month ago, when I tried to get my bike inspected, and it failed because the brakes were dragging.

So I replaced the inner seal, and the dust boot on the front brakes and could not get them to bleed. I noticed fluid on the right side, and when I took it apart, a chunk of the seal was missing.

Replaced the seal. Still no full brakes.

I figured the rubber from the speed bleeders was gone and that could be my trouble. Tired teflon. nothing. Tried RTV, nothing. Tried new bleeder from the dealer $$$ nothing

I picked up a vacuum bleeder and ran 2 quarts through. Nothing.

I'm open to any ideas.

Any way to tell if one caliper is working more than the other? or better yet, is there a way to disable one side and see if I can get a full pedal with one brake, then try the other side to see if I can localize what caliper is causing me trouble?

Thanks

G

Some clarification may help regarding which caliper was dragging, and which brake components were worked on -- master cylinder (front and/or rear)? -- which of the three calipers? -- which seal(s)? -- which dust cover(s)?

Is the master cylinder failing to pump fluid into the brake line?

Good Fortune!

Thanks Patton.

My apologies for not being clearer. The front two calipers where dragging. I replaced the piston oil seal ( 43049-002 ) and the piston dust boot ( 49006-1043).

The master was rebuilt a few months ago, and I was able to get a full pedal prior to rebuilding the calipers.

Hope that helps.

G

Thanks.
Am understanding: new caliper seals and dust covers, with a properly functioning master cylinder.

Is the main issue at this time a lack of success in bleeding the front brakes to achieve a tight hard lever when squeezed?

Or is "brake drag" still a suspected problem?

Good Fortune!

It is the lack of success of bleeding the brakes. The best I could ever do is mild success just under where the lever touches the grip.

Lots of people do it in reverse. Get a syringe or another low pressure implement, and put brake fluid in through your bleeders. You need to fill it with clean brake fluid and then clear it of air, hook it to a open bleeder, slowly fill. Air will bubble up through the return port in the master, but you will also add fluid this way, so you need to be careful not to overfill the master.

Thanks Motor head. Any idea where to get a large syringe from?

got a dairy supply business close by? they will have some

ggenovez wrote: Thanks Motor head. Any idea where to get a large syringe from?

Walmart, Rite-Aid, Target, etc. Basically any place like a drug store. They should have more than just the Needle hypodermic size.

When filling the brake system with fluid, may use an inexpensive rubber ball style syringe with a short hose attached to the end which connects snugly over the bleeder nipple.

M/C reservoir is uncovered (to watch the fluid rise up inside).
Bleeder nipple is slightly loosened.
Brake hand lever isn't being squeezed.

Suck a load of fresh "unskaken" fluid into the syringe, remove from fluid and press out the air, and re-immerse and re-suck, repeat as needed until the syringe is almost full.

With the tube pointing upward, squeeze slight pressure on the syringe to expel all air (fluid is barely escaping from end of attached hose).
Holding it in this condition (no air in the syringe or hose), attach the hose onto the bleeder nipple.
Squeezing the syringe will now push fluid from the syringe through the hose and into the bleeder nipple.

Don't release squeeze pressure on the syringe while attached to the loosened bleeder nipple.

If more fluid becomes needed in the syringe, tighten the bleeder nipple before relaxing and removing the syringe.
Refill the syringe and resume the filling process as earlier described.

As fluid fills the system, it will eventually appear and rise up inside the master cylinder.

When the M/C becomes filled, tighten the bleeder, without having relaxed pressure on the syringe.
Then remove the syringe and hose.

Normal bleeding procedure should now expel remaining air from the brake system.

Good Fortune!

Good Fortune!

I found a nice sized syringe in Walmart in the oil section. It is for measuring small amounts of 2 cycle oil. It saved me a ton of work changing oil in the forks.
Wayne