Yes, a bit of drag, but more than normal. Basically when I spin the wheel it turns about 3 or 4 total revs and then stops because of the drag. Do you think under normal riding conditions this would be different?

 

Sounds a little more grabby than normal. I'd probably ride it a bit and see if it loosens up, but that's just me. Make sure you don't have too much fluid in the system. Does it get worse when the brakes get hot?

Worst case, I'd recommend removing the whole front brake from the bike including the master cylinder off the bar, move the whole assembly to the bench and mount the master cyl in a vice, while stretching the caliper out so that it is roughly level or slightly below the master cylinder. Remove the pads. Clean up the caliper real well removing any dirt. Take the top off the fill reservoir, make sure you have some new brake fluid, then start pumping the lever, never let the fluid level go too low such that it sucks air into the line.

This will pump the pistons completely out of the caliper. You may have to hold one back so that they both come out evenly.

Go ahead and remove the pistons. Clean them up real well. Brake cleaner works well. Be careful with that stuff, though, it can blind you if you get it in your eyes. Inspect the calipers around where the pistons go, make sure there is no damage to the seals. Keep pumping fluid in from the master cylinder until it is overflowing out of the caliper wells. Then pour some fluid in just to be sure they are completely 100% full, you don't want any air bubbles in there.

Reinsert the pistons back into the caliper wells, start them slowly. Use a C clamp with an old brake pad to slowly push them back down in together, both at the same time. You might want to place a bucket under the master cylinder as this will force brake fluid back through the lines and out the master cylinder, it will also remove any air that might have been trapped in the line.

After you get the pistons all the way seated, clean up the fluid off the caliper, reinsert your brake pads, then start pumping the master cylinder again to close them up, adding fluid again to the master cylinder as necessary - like before, do not let it drop so low that it sucks air.

As the pads get closer to together, insert a 5 or 6mm allen wrench in between and let it clench it. This will keep the pads far enough apart that you can slip them back over the rotor. With the allen held in place, continue pumping the master cylinder, and top it off with oil. That's going to be very close to the correct oil level, put the cap back on the master cylinder.

Reinstall the master cylinder and caliper on the bike. With the wheel installed as well, and the rotor now in between the pads, pump the master cylinder until the pads grab the rotor.

That's a pretty full brake service. I've done it to my KTM a time or two, it does wonders for the brake feel, should do the same for the KLX. If it is still grabbing after that good cleaning and fluid replacement, then perhaps one of the pistons is damaged? Or maybe the cylinder well or o-ring seal is damaged? But that's about all you can do without taking it to a professional or buying new parts.

Here are some photos of what I'm talking about, hope it helps:

 

Dang man, that's a right up. Thanks for that. It sounds a little intimidating but your pics make it look a little easier. I will give this a shot this weekend when time permits. I will let you know how it goes. Thanks again, Daniel.

 

Another diagnostic question for you... are your brake rotors really hot after you ride for a while, in addition to the noted squeaking? If one of the pistons, or the master cylinder is a little sticky and creating mentionable friction, that should result in some pretty good heat. I wouldn't touch the rotor obviously, but you should be able to just hold your hand near it and feel if heat is radiating off of it. On cars with a sticking caliper you can feel heat nearly a foot from the outside of the wheel, you'd have to be much closer in this case, but if there's no heat at all, I'd look for alternate sources of squeak.

Oh, and great write up on that brake service "Nobrakes" <(kinda ironic, yes?) almost makes me want to do a brake service just because it's there!

 

Dirt or corrosion on the caliper pistons making them not retract properly. This is not uncommon if a rider does much off roading and dirtier riding, then powerwash the bike. Blows water past the external seals. I don't know if that fits you, but even if it doesn't that can still be the problem. It's happened to me before, very similar caliper too. I don't pressure wash my bike either.

 

Nice write up and I like the method of fully bleeding the brakes but can you replace it on the bike without haveing to remove the hose from the mastercyl(Potentily introducing a little air again)? I had to drive the truck to work today due to heavy rain or I would go look. But I am pretty sure I could not remove/replace my brakes as a sealed unit.

I had sticking pistons on my F150 and had to replace the entire calipers both sides about 6 months apart. Like mentioned above I got a lot of heat buildup from the brakes sticking. I could spit on the rim and it would sizzle. Hope you can sort this out without replaceing pistons and calipers.

Cheers Jim

 

Just my thoughts: I'm pretty sure this whole problem is due to sticky caliper pistons. Normaly they are pushed back a bit by the minimal warp which is in all rotors. Also: to get both pistons to come out simultaneously is hard to achieve. They would both need the exact amount of resistance. If piston 1 needs 30.0 psi of pressure to move and piston 2 requires 30.5 psi of pressure to move, guess which one will move first. Good luck and I'm sure you'll get this sorted out in no time.

 

Okay, I went back and cleaned around the pistons with brake fluid, instead of that teflon crap. I think the teflon crap is too sticky in such a small space that exists between the pistons and the housing of the pistons. The brakes do seem a little better noise wise, but there is still a drag when trying to spin the front wheel when it is in the garage. So I am, not sure i solved anything. I only rode a little bit and it seems to ride fine, but before I had the squeel only after riding it for a period of about 5 to 10 mintues. Anyhow, another longer test ride to come. Although, now with trying to bleed the brakes a bit I don't think they are as responsive. I am thinking maybe I just need to top of the master cylinder. Although, the fluid level looks good in the window on the master cylinder so I don't know. I suppose the front brakes shouldn't work so good that your front wheel skids, otherwise I imagine you would lose the ability to steer. Is that a correct assumption. And I would guess that the rear brake is a faster braking caliper as it will lock up the back wheel, if needed. Are my evaluations correct?

No brakes, I didn't go to the extent that you described but I did use the trick with the clamp to get the other piston to extend out for cleaning, very helpful. When I pushed them back in I could feel the resistance resolving as if they just may have needed a really good cleaning.

 

dacoontz, you're right about braking power front and rear. The rear can be fairly mediocre and still have enough power to lock up. And on dirt, frankly I don't want a super quick and powerful braking action front and rear. On a groomed motocross track or tacky, loamy soil, I guess it's not as big an issue, but where I ride in rocky, often loose terrain, grabby, super powerful brakes aren't a big plus. A good, firm but linear brake power is ideal for me on dirt. I use the front brake probably 80 to 20 over the rear brake on both pavement and dirt, but I'll take a nice linear, moderately powerful brake over a super powerful one any day for my use. Now, super motard guys or bikes that are used predominantly on pavement benefit from really powerful brakes...as long as the tires are decent. Everything's a compromise...and then of course there's always the issue of preference.