Crappy brakes on my 02KX250

[Bandit9]

I just bought this sweet KX250 w/ Eric Gorr 310 kit in it. I love the bike. The brakes just suck ass though. Is this a common issue w/ KX's?

[gowen]

"suck ass" does not give enough information about the brakes. I have a few KX's now, one being a '01 250 and a '90 500. Both have near perfect brakes, with the 500 about in the ok catagory.

[mikesmith]

You need to bleed the brakes often on the older 250's,you can go to an oversize rotor to.

[Bandit9]

GOwen, they are bled with fresh fluid, pads have plenty of pad left, rotors are not worn, lever+pedal are adjusted, and the brakes feel very weak (aka "Suck Ass"). I was wondering if this is common with with KX's from that year. Or do I need to not waste my time trying to get the stock setup to perform and just spend money on steel brake lines and other rotors and pads.

Mike, thanks for the info. How often are we talking here?

[Rowdy-Yates]

Bandit what year are we talking here? Is it front or back? A air bubble will give you that feeling also. Look for weak spots in your lines basically same as an air bubble.

[gowen]

Bandit, that sounds like you may have a small leak in your line, which usally indicates the calipers needing rebuilding. I do know my KX500 had horrible brakes for awhile and I thought I had bled them throughly, but it ended up having some air in the lines. I imagine that is the problem, but I would rebuild it anyway, just to be sure. WHat year is your KX?

[Bandit9]

The KX is a 2002. Rebuilding the caliper, hummm.....never done that before. How involved is this? Costs? Thanks for the help guys.

[KXcam22]

Bandit,
   I think a one or two finger lockup should be about standard braking power you should expect on a KX.  For a 2002 I doubt that you need to rebuild anything (but don't rule it out).  As everyone else has mentioned, it sounds like you have some air in there.  Sometimes it is pesky to get out.  Maybe try hanging the caliper overhead, tap the lines and master cylinder with a hammer (lightly) and leave for a hour before bleeding. That should get the air out.  Hope this helps. Cam.

[Bandit9]

Thanks Cam. I am going to bleed them again tonight.

[KaTooMer]

Rebuilding the caliper, hummm.....never done that before. How involved is this? Costs?

It's pretty easy, actually. Rebuilding the capliper is really just replacing the pistons and/or piston seals. The two pistons, or "pucks" as I like to call them, aren't really held in there by anything except the seals. With the caliper removed, grab the front brake lever and let it push the pucks as far out as they can go. Drain the fluid, then yank out the pucks (use something that doesn't bung up the pucks if you plan to continue using them, and prepare to get some brake fluid on you even though you thought it was all out of there). You can replace the pucks and the seals together, or just the seals. Unless you see something noticeably wrong with the pucks, I'd just replace the seals and see if that helps (and this would be after you try all the various bleeding techniques). The part numbers are on buykawasaki.com. Looks like the pucks are about $16 each on Ron Ayers and the seals are either $8/each or $4/each, depending on which one (looks like each piston has two different seals). I'd bleed that thing everywhich way before rebuilding the caliper.

By the way, Ron Ayers has never let me down...very good delivery times and pretty good prices. You can copy part numbers from buykawasaki.com and paste them into the "part number search" box. Brings up the item and the price.

[Bandit9]

I bled them this afternoon. They feel the same as before. I ran some sandpaper on the rotors. A guy in another forum mentioned that the rotors might be glazed. It was dark, so couldn't test them out. I ordered some stainless steel brake lines today, so if the bleeding, scuffing, steel lines  doesn't help, then I will be rebuilding the caliper. Thanks for the replies.

[John]

I had the same problem, check out this thread;

http://www.pitbull-racing.com/index.php?name=PNphpBB2&file=viewtopic&t=392

//John

[Bandit9]

Interesting. Thanks John.

[Rick]

Use only original KX pads.  Nothing else compares.  The KX250 should stop just fine once the air is out, the pads are stock, and the rotor is not glazed.

Rick

[KaTooMer]

Use only original KX pads.  Nothing else compares.  

I agree with that completely. I tried EBC sintered metal and they took a long time to break in, never did give me the same stopping power. The KX pads aren't cheap (over $30), but it's sort of a safety thing for me. I want to stop when I want to stop, not 10 feet later.

And while we're on this subject, loc-tite the front brake pin!! My '03 KX250 doesn't have the plastic cap thingie like the rear caliper has. You'll know rather quickly when the pin is gone.