mntbiker_ken

I have a re-occuring issue involving the front brake on 3 different bikes now and can't figure out what is causing it or a definite way to fix it.

To transport my bike(s) I take off the front tire and lay it in the trunk, disc side up.
I put the rest of the bike in the back seat area...it has plenty of room....it bumps around a bit getting it in there...but no certainly no worse of a beating than it would take on a trail.

Then, when I get to my destination, I take my bike out, go to put the front tire in the forks and find that I can't get the front tire to go in because the distance between the brake pads have narrowed substantially and not enough room for the disc rotor to fit between. I don't know what is causing this!

With 2 of the bikes that use cables/mechanical disc brakes I had been able to pump the brake a few times and/or jiggle things around and it seems to get back to normal. One time I adjusted the cable to compensate.

But today, with a different bike that has hydraulic juicy 5 brakes......same thing. Went to go put the tire in and initially couldn't get it in due to the brake pads. I finally jiggled it in there.....but it was tight and the tire would not spin freely. I rode on it, thinking it would eventually work itself back....but it never really did.

Anyone know what could be causing this (in laymens terms please) and what I can do to adjust that when it happens?

Thanks much!
Ken

mntbiker_ken

ok...think I figured out my own question...which here it is....but now I have another....please read.

The brake lever probably was getting pumped a few times getting the bike in and out of the car. WIth no wheel in place, apparently the pads close together..........I did not know this!!

I need to get the spacers that go in between the pads when transporting without the wheel in place.

In the meantime, I understand you use a 10mm box wrench to push the pistons back in.
Anyone want to shed a little more light on this part? I don't have a 10mm wrench handy so tried using a screwdriver but the pistons don't seem to budge! Does the 10mm wrench make a lot more difference than using a screwdriver to push them back in? Are they supposed to be so hard to push back in?

Just to be sure.....the piston is that whole circular unit on each side and not just the little square shaft in the center right?

Thanks for the help!

mcoomer

Yes, the pistons are the circular peices inside the caliper. I've always used a large flathead screwdriver to force the pistons in. I've got one that has a short stubby handle with a wide blade that does the job very well. Leave the brake pads installed, get a wide flathead screwdriver, and firmly but smoothly force the pistons into the caliper. You shouldn't have to move them much to be able to get the rotor to squeeze in there.

Mike

ed 

I use a "mini flat bar" that is 3-4" long and ~ 3/4-1" wide:

Quick_Torch C5

Not trying to be mean, but not squeezing the brake lever with the tire off will solve all your troubles. My wheel comes off every time I transport, never had that problem.

mntbiker_ken

Quick_Torch C5

Glad to hear you have been so successful in transport. As mentioned, at first I didn't know WHAT was causing the problem. Now that I am pretty sure the levers were ACCIDENTALLY getting bumped around......of course I will try to make sure they won't get squeezed. Getting the spacer certainly won't hurt.
Thanks for the great advice and keep up the good work of not squeezing your levers!

born2bahick

Signature worthy example of PC reply!