Front brakes - help

[1887]

I am a newbie, I have already done some research to get to this point, here is my dilemma:

The front brakes were dragging, I removed one caliper and the other side dragged as well. I took the other side of and put the first caliper and it still dragged.

I performed the spooge hole remedy. I pulled apart the front MC and cleared out the hole with a .012" wire (high e string on an acoustic guitar) but could not fit a .016 wire (the b string). How far is the wire supposed to be able to drop down? It went about 1/2" before hitting something solid. The rubber diaphragm on the top of MC looks like it is in good condition.

The pistons looked corroded, one was worse than the other. I replaced the pistons (bastards to get out), seals, boots and bled the brakes. The draggy noise is still there!

I loosened the axle, took the fender off and spun the wheel - still dragging! I pulled the calipers off again , to determine if it is one or both. Both sides are dragging.

Am I safe to assume the problem lies in the MC? Got any advice?

[bikerphil]

I replaced the pistons (bastards to get out), seals, boots

On the calipers, did you scrape the corrosion out of the grooves the seals sit in? They need to be very clean for the pistons not to bind.

[motoman]

I am a newbie, I have already done some research to get to this point, here is my dilemma:

The front brakes were dragging, I removed one caliper and the other side dragged as well. I took the other side of and put the first caliper and it still dragged.

I performed the spooge hole remedy. I pulled apart the front MC and cleared out the hole with a .012" wire (high e string on an acoustic guitar) but could not fit a .016 wire (the b string). How far is the wire supposed to be able to drop down? It went about 1/2" before hitting something solid. The rubber diaphragm on the top of MC looks like it is in good condition.

The pistons looked corroded, one was worse than the other. I replaced the pistons (bastards to get out), seals, boots and bled the brakes. The draggy noise is still there!

I loosened the axle, took the fender off and spun the wheel - still dragging! I pulled the calipers off again , to determine if it is one or both. Both sides are dragging.

Am I safe to assume the problem lies in the MC? Got any advice?

Only fluid return retracts the calipers, and they do 'drag' on rotors. No different than automotive, unless theirs wire spring clips that help that return, in which case their is no 'drag' as is the case with all four disc on my F-350 diesel.
I presume wheel spins freely without calipers?

[1887]

yes, I did clean the grooves out, they look pretty good. There is more frag than there should be.

How big is the spooge hole? I am going to go clean it out again.

[mack]

did you ensure

the respirator holes are clean at the front of the plunger assembly in the m/c. If the fluid can't bleed back through those holes the brakes can't release. I don't have one handy but if I remember there is something like a spring loaded star plate covering them that can't be removed. Ultra sonic cleaner or submerged in a pot of boiling water for several minutes may clear the holes.(remove the rubber stuff first)

[1887]

Yeah, Mack I think you are right. everything else is clean

[WMarshy]

Heres a little How-To on the caliper rebuild part but, it sounds like you have to clean the master cylinder.

http://www.xs11.com/forum/showthread...ht=front+brake

[crazy steve]

You'll never eliminate all of the drag as that's a characteristic of disc brakes. When the front wheel is off the ground, if giving the wheel a good hard spin results in the wheel turning around three or more times before stopping, you're good.

Do make sure that the caliper is free to move back and forth in it's mounting bracket. If it's not 'floating' properly, you can get extra drag. I like to use some rubber grease on the rubber bushing installed in the caliper body that the attaching bolt goes through. Also make sure this area is clean; corrosion here will inhibit free movement.

[1887]

It took me a little while (busy with other projects) but here is what I did over the weekend:

Rebuilt the front Master Cylinder, it was dirty and nasty inside and the snap ring was a bit$! to get off. I can see why I had to clean out the spooge hole every 3-4 rides, you could grow potatoes in the MC bore - all kinds of crap in there. I cleaned it out the a softwood dowel and steel wool, put a new rebuild kit in and bench bled it. I also put new stainless lines on and cleaned out the splitter block. I already rebuilt the calipers with new pistons and seals. I filled it up with dot 4, vac bled it and presto - I have brakes.

This weekend I will do the rear.

[BowlingSS]

I am glad you got it working great again. Where did you get the rebuild kits?

Bill

[1887]

I bought everything from Parts N More simply because they are located in Canada and its cheaper shipping. Any thoughts regarding this vendor?

[MaximPhil]

Hi 1887,
I have deal with Patys & More many times. I have been satisfied with the parts supplied. Much of their stuff comes from Taiwan. Market pricing and shipps within Canada makes it positive for me.
Phil

[1887]

I am glad to hear that.