[sub6]

This has happened enough times that it's gotten pretty annoying. When I bleed my Hayes, everything seems fine. The lever is firm, engagement point is spot-on, everything works.

But the next day, the lever pulls to the bar before the pads actually engage. I always get out the syringe, inject more fluid in thru the caliper, close it up (this isn't bleeding, just topping off the fluid), and from then on everything is fine.

Is there any reason why this happens, and any way I can get it to take enough fluid on the first try? I don't push my pads back while bleeding. I don't try to squeeze too much fluid in (i.e. pressurize the system) while doing the inital bleed b/c I'm afraid of rupturing the bladder, which Hayes has warned about.

oh ya one more thing - the only time I EVER bleed my brakes is when I'm replacing a hydro line, if that makes any difference to anybody answering this.

 

[Repack]

Try topping off at the lever using the bleed cone. Flip up the lever to the bleed position when doing this. Take out the screw, put in the cone, fill the cone with fluid and pump the lever until it won't take any more fluid. Repete process as needed. Push the pistons in with the screw still out. This will keep the system from becoming pressurized.

 

[llkoolkeg]

...me from hitting Wintergreen with you guys last time. We never found out definitively what the problem was but replacing the caliper and line eventually fixed things.

BTW, do you know how to rebuild calipers? I am reluctant to throw the old one out until I determine whether or not it truly is shot.

 

[mrbigisbudgood]

Originally posted by llkoolkeg
..
BTW, do you know how to rebuild calipers? I am reluctant to throw the old one out until I determine whether or not it truly is shot.

Buy a rebuild kit and a six pack and I'll rebuild it for you.

 

[llkoolkeg]

Originally posted by mrbigisbudgood
Buy a rebuild kit and a six pack and I'll rebuild it for you.

Well, the 23rd/24th is the next opportunity for me to ride somewhere besides Gambrill/Watershed. If we are able to hook up that w/e, you'll have yourself a deal. Too bad ya never get to make it up this way. We had such good trail magic this past Sunday. You could have appreciated it.

 

[Repack]

Originally posted by llkoolkeg
...me from hitting Wintergreen with you guys last time. We never found out definitively what the problem was but replacing the caliper and line eventually fixed things.

BTW, do you know how to rebuild calipers? I am reluctant to throw the old one out until I determine whether or not it truly is shot.

I have never seen a caliper wear out. You can get the piston kit for about $7 per side. A little teflon plumbers tape on the bleer nipple threads will also work wonders.
There's this insane guy who comes in to the shop I used to work at all the time. He rides his bike 365 days a year. He had a set of pistons completely seize from salt corrosion. New pistons fixed it.
This is the dude. No, this is not a joke. He suffered some sort of head trauma or mental breakdown, the exact nature of which is up for debate. The 2 most often qouted explanations were that he either crashed a motorcycle sans helmet while drag racing a car in the rain, or that the Air Force drove him nuts. And yes, that is a Mongoose mainframe with a home-made rear end. He has another bike with a massive dirt bike shock crammed into it.

 

[sub6]

Originally posted by Repack
Mongoose mainframe with a home-made rear end.

Oh my. The falling rate on that rear end is just TERRIFYING. Not to mention that it looks like the "seatstay" would fold into the "chainstay" if you so much as sat on the bike.

Is he a messenger by any chance?

 

[Rev.Chuck]

Have you tried (gently) pumping the lever as you bleed the system. If I remember the instructions, they either say you should not or don't need to but I did once when I had one that did not want to bleed out and "poof" ready to go. I have done it since and never need to rebleed.

 

[sub6]

thanks Chuck, I'll try that, maybe combined wth Repack's suggestion - I've never pumped the lever I guess that could well be the problem...

 

[Repack]

Originally posted by sub6
Oh my. The falling rate on that rear end is just TERRIFYING. Not to mention that it looks like the "seatstay" would fold into the "chainstay" if you so much as sat on the bike.

Is he a messenger by any chance?

He is not stable enough to hold any sort of job. I heard that he gets come sort of disability check from the government. All he does is ride his bike. 365 days a year. And he's always dressed the way he is in the picture. I feel bad for the guy. I think I only saw him once without a fullface on. At some point, at least 8 years ago, he took a welding class at a community college and still has access to the welding stuff. He spends a lot of time rebuilding frames. He still has some alignment issues though. The bike in the picture has no rear brake mount.

 

[llkoolkeg]

Originally posted by Repack
He is not stable enough to hold any sort of job. I heard that he gets come sort of disability check from the government. All he does is ride his bike. 365 days a year. And he's always dressed the way he is in the picture. I feel bad for the guy. I think I only saw him once without a fullface on.

Or is this a purely psychological phenomenon?

 

[Matt D]

Originally posted by Repack
The bike in the picture has no rear brake mount.

I don't think you'd want to put anymore forces into the equation with that bike

Sub6, You've probably checked already, but make sure you've done EVERYTHING according to the book. Lever at the correct angle with lever above the caliper, push the pistons in, tap the caliper/lever to release air bubbles blah blah blah.

I can't say I've had the same problem, but I've had a couple of "duh" bleeds where I've had to go back and do it again.

I haven't seen a caliper fail before, besides the spring mounts breaking. But I've seen quite a few master cyclinders develope problems.