Fixed my sticking front brakes today FINALLY!

I absolutely hate when I cannot fix something, it just eats away at me as an unfinished project.

Last night I pulled all the lines off my front brakes and flushed them to be sure they were clear, this is after a week of rebuilding calipers, polishing pistons, thinking my rotors are slightly bent, rebuilding the master cylinder, running wire thru that tiny hole numerous times. Bleeding them over and over. All to no avail.

I finally decided parts for this bike arent that hard to find, mainly the master cylinder I was so hesitant to modify, so I bit the bullet and drilled that teeny tiny hole out, with the smallest machinist drill bit I have (no idea what size). It is still considerably smaller than the large hole in the MC, and Whallah, my brakes are fixed.

I disassembled and cleaned that damn hole like 4 times now. It was definitely clear. I could previously get the brakes to lock in my shop by just pumping them, then I would pop a bleeder, or a banjo bolt and they would free.

They now even lock to a stop in the lever, I remember my brother in law telling me how SS lines make your brakes lock firm when you pull the lever after pointing this out on a Ducati I owned, my VFR's front brake now has a real stop in the lever like that or close.

And they also bleed much better, I guess that tiny hole didnt let much fluid thru before when the master was at rest.

Im satisfied now, I can sleep again. I've owned ALOT of bikes, new and old and I've never heard of this problem.

I thought I would post this in a new thread in case anyone is hesitant of doing this. The bit I used is less than a 1/16th inch, I can tell you that much. I put 80 miles on the bike tonight, and trying my damndess to get them to heat up, lock up, no luck! Thank God.

This whole brake project reminds me of a 78 Trans Am I restored awhile back that I could not get to the brakes to bleed. It had a rusted rear brake line that would allow air in, but not leak fluid out. Whoever would of thought that could happen! Again after I replaced everything else first.

 

Took a while for you to listen but glad it is fixed

 

Could you elaborate? Which yr., model of bike? Which hole? Any pics?

 

TOTALED TL------------Its on my 86 VFR700, in the brake master there are two holes in the bottom of the reservoir, one is open to see, the second is covered by a shiny steel deflector that is pressed into the recess of the open hole you can see. This second hole under the deflector is really really tiny, I drilled it larger slightly and it solved my locking front brakes.

What finally led me to drill this was, in the past when I've bled bike brakes, there is usually some kinda fluid pumping splashing action going on in the master when I've bled brakes, my VFR with sticking calipers, did not do this at all. I drilled out that tiny hole, and now when you pump the master something is definitely doing something inside there. I cant explain it, the tiny hole was clear before I drilled it out, no idea at all. They must be made to work with the tiny hole, mine didnt.

Sorry no pictures, when im on a roll, I always forget the camera LOL

 

Mastercylinders all have the tiny bleed hole, nothing special about the VFR cylinders, rear is the same as well

 

all same concepts, I would be careful using drills to increase holes, they have them for jets which can play havock when your trying to re-jet someones elses problems. I use plastic and wood to clean delicate parts and use a drill only to reem out crud that accumulates in hoes (holes) under magnification. Anyway, servicing brakes is a chit job, but the pay-offs are sweet as you experienced for yourself.

 

I did the same to my clutch master last year. Seemed like the way to go to me.

 

If you're gonna drill, the mc should be disassembled first to avoid damage.

 

Was a vigorous discussion on the Supersport forum a few months ago about drilling the hole bigger. I think it ended up about 50/50

 

I'm glad you got it taken care of. I'll be sure to check mine, although I'm pretty sure they just need rebuilt.

I also found that an ultrasonic cleaner is simply outstanding for cleaning hydraulics. I've heard that some ultrasonics can damaged machined aluminum, but I've never seen that with my high frequency ex-dental cleaner.

 

We had a nice ultra-sonic cleaner with its own "juice" in it. It was a good unit with a heater and agitator. I used to stick my gold wedding band in there with no ill consequences. This bastard/idiot/hack-mechanic that we had working for us who had one lung from cancer broke it though. His personal facts just make the story that much better :loco: Nowe its busted and the management won't fix it! I would hazard to believe that it would not damage un-machined aluminum.

What I plan on doing in the future regarding brake service is one: remove front wheel; two, remove rotor/carrier - mask carrier and use the glass bead/walnut air blast cabinet to prep the blade for the new brake pads. Just doing this for chits and grins basically, because there is no real grease or goop on the blade. Anyway, brakes are often neglected until they need major over-hauls. I would not use a drill to open up a hole in a master cylinder either too. Unless there was severe crud in there and then, if I did, I would do it under excellent magnification :crazy: thats just me though. eace: