Hi all,
Ok so my brakes start to bind after they warm up a bit, to the point where they start to stop my bike from moving. I wait on the side of the road for 10-15 minutes and they let up and I can start using them normally again. But the bike cools down and the next day it's the same issue. I had to switch to the backup bike in the mean time.
So I was looking for brake parts to buy either a rebuild kit or just everything separately and I couldn't really find a rebuild kit for our specific bike. I have a 93 BTW. SO I take a look at the part numbers using several different sites and what I found was that the same seals, boots, bleeder screws and their caps, pistons, etc. Very many parts were exactly the same for newer bikes (way to economize Honda). Although, it just goes to show it's good stuff huh?
Anyways my questions are the following:

1: Would it be a plausible idea to order a rebuild kit for a newer bike that uses the same part number seals (such as a Goldwing or a cbr250r)? Unless of course one of you smart fellows can show me where to find a rebuild kit.

2: In the case where I might just decide to buy everything separately, what parts should I replace when rebuilding the calipers?

3: This is a caliper rebuild job isn't it? I've read elsewhere it might be the MC....

Just for added info, the brakes were functioning fine but I refurbished my forks due to a leak and found the pads were sorely worn so I replaced them and I got air in my system due to carelessness. When I bled the system and put everything back together I found I had this problem so I was just assuming a piston might've popped out of it's seal without my noticing. Anyways I don't want to cut corners when it comes to my brakes so I thought I'd ask for advice before continuing.

Thanks in advance!

 

The "accordion" seal on the piston is merely a dust seal, the actual pressure seal is the rubber ring between the piston and the caliper, if the piston would pop out of that you`d know. Is it a caliper or a MC job depends on what condition are your pistons, if they are rusted or pitted you might have to replace the pistons as well, a little surface rust can be brushed away with some fine steel wool or the likes, but if the pistons are badly pitted they will continue sticking after a thorough service. Most brakes I`ve serviced have been on cars (way more piston movement) but almost every time if a pushed in piston starts to stick it`s because it`s rusted from the tip and when pushed in jams there.

For the #1 Q I do not know the answer but am interested to find out if someone else does.

 

My brakes were sticking so bad that when I backed my bike down the loading ramp the front wheel was locked up, due to hard trackday braking pad material buildup. So what I did was remove one caliper at a time, squeeze brake lever to force out pistons mostly but not all the way remove pads then scrub caliper and pistons with hot soapy water and blew dry with compressed air. Then lubed piston with a drop or 2 of brake fluid and squeezed pistons back in. Put everything back together. No more sticky brakes.

 

Thanks for the info guys,
I'm willing to try replacing with alternate parts only because the part numbers match but I peeking into the brake pistons edges and they were rather brown with rust although nice and shiny towards the insides. I don't know if they're pitted through but I'll try coalminer's idea and try to just remove the surface rust using the same dust and oil seals. If it works, great, if not, or if the pistons look bad enough, I'll crack the calipers open and replaced all rubber parts and if necessary the pistons as well. I'd probably get to this next week as I don't have the parts nor am I willing to jurry this job up.
I'll be sure to update in case anyone else has this issue but Mattson's thought of rust blocking movement seems to me like the most likely.

 

Wow, just had the same problem yesterday when riding. One of the caliper kept seizing and was hot as h**l. The other one was just fine. Solved it by letting out a few drips of fluid and releasing some of the tension of the bolts securing the caliper to the bracket. A kick or two and I was good to go, for the moment. I'll do a proper service once winter kicks in for real.

I bought my rebuild kit off eBay: banks.motorcyclemailparts on eBay

 

a kick or two always solves everything right?
IDK why that had me laughing so much.

anyways yea I tried banks.motorcyclemailparts on eBay but they have 0 items on sale right now....I sent an email in case he gets any new ones but thanks for the intel.

 

I forgot to post back last week, (in case anyone was waiting) sorry...
Anyways, decided to take the calipers off the bike and clean them up and realized that there was quite a bit of rust beginning to build up on the pistons (see pictures).

I popped the pistons out of their sockets and took a peek inside and as I suspected (and as someone else had suspected above me as well), after several years of not caring for them, sludge begins to form between the pistons and the reservoir. This is: old brake fluid, probably absorbed moisture, rust, dirt, brake dust who knows!? But it's there and It just needed a bit of cleaning. Before installing the new break pads everything was working fine so I figured the same seals would still work OK, and they have been up until now, 2 weeks later. The rust that was building up had been either sticking to one or both of the seals (and would've torn them had it continued, or the sludge in there had finally said "screw it lets clog this bike up for good!"

BTW, I didn't use anything to clean them other than paper towels or a dry clean rag (which ended really dirty). Anything else in there seemed like a contaminant. Just kitchen paper and elbow grease. The pictures show a good before and after of how most of the pistons looked before I cleaned them (and obviously how they ended up) and the junk inside the pistons.

If this helps any one in the future then great!