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2000 KX 250 Brake Problems

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I have a 2000 KX 250 and the front brake lever during my last ride became hard to pull and the front brakes don't have very good stopping power. It appears that the problem is somewhere within the lever. I removed the caliper and cleaned everything very well and everything appears to be working properly on that end. Any help? Would like to ride this week but need front brakes.

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I've had to replace the plunger on the lever end before, but it was on a Yamaha. You may want to take it apart and clean it out....but don't use parts cleaner or gasoline or anything but soap and water. Chemicals will swell the rubber parts and you'll have to buy new ones.

Karl

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I've used fresh brake fluid too. Along with a bowl and your brother's tooth brush. Give it a try.

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I've used fresh brake fluid too. Along with a bowl and your brother's tooth brush. Give it a try.

LOL, Britt!

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C'Mon guys how about some help here??? I took my master cylinder off the bike tonight and once the brake line was removed it took the stiffness out of my lever. What should I be looking for in the cylinder and if this doesn't work what should I examine next?

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I had the same type of problem on my 01 250 and it was the brake pads. Dont know if this is your problem but you never know.

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C'Mon guys how about some help here??? I took my master cylinder off the bike tonight and once the brake line was removed it took the stiffness out of my lever. What should I be looking for in the cylinder and if this doesn't work what should I examine next?

Does it feel like the piston on the brake pad/caliper end isn't moving? You may need to take the assembly apart and look to see if there is crud built up behind the piston's seal. If it does have dirt or crud behind it, then that can cause your piston to stick and not move your brake pad against the rotor.

Let us know if the piston is moving freely or if it's sticking or binding.

The plunger I was talking about in a previous post is in the master cylinder. It's what the brake lever is pushing when you apply force. If it looks like the plunger is clean and moving freely, then it's probably the piston in your caliper. Dirt can get behind it and cause corrosion and problems.

Your brake pads are good, correct?

Karl

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Does it feel like the piston on the brake pad/caliper end isn't moving? You may need to take the assembly apart and look to see if there is crud built up behind the piston's seal. If it does have dirt or crud behind it, then that can cause your piston to stick and not move your brake pad against the rotor.

Let us know if the piston is moving freely or if it's sticking or binding.

Karl

I think this is my problem. I just picked up my new to me 1999 KX250, and noticed the front brake Not working i.e. no pressure at all, so I asked the previous owner about it, he said it prolly needs fluid, well, I took the caliper apart and there's so much built up fine dirt all over that it actually stained the caliper, yup, it has light brown stains..no funny comments please:p

I'll have to put some compressed air into the caliper tomorrow, and look at the pistons, my guess is there's a ton o crud in there..:applause:

Other than that, I like the bike..:applause:

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I think this is my problem. I just picked up my new to me 1999 KX250, and noticed the front brake Not working i.e. no pressure at all, so I asked the previous owner about it, he said it prolly needs fluid, well, I took the caliper apart and there's so much built up fine dirt all over that it actually stained the caliper, yup, it has light brown stains..no funny comments please:p

I'll have to put some compressed air into the caliper tomorrow, and look at the pistons, my guess is there's a ton o crud in there..:applause:

Other than that, I like the bike..:applause:

Good deal. It's probably just crud and unless the piston is corroded really badly, you may just need new seals. I'd order those now so that they can be on their way....chances are you'll need those replaced. They're relatively cheap, too.

Karl

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Thanks kargo...did the same thing on my gixxers..for some reason the seals in the pistons would go bad in a hurry...think I'll grab some new brake pads while I'm ordering the seals..

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You may want to price a new piston too if they can get you one. Those things are considered disposible just like your pads only no where near as often. Maybe they have a rebuild kit you could get, that would be even better. Use DOT 4 as your assembly lube too unless the kit comes with special grease. Oh yeah, blow out your brake line and check the rear while your at it.

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Welp, it turned out to be a bad master cylinder, so I rebuilt it, cleaned the crap outta the brake system, and installed new pads. Works great now..:applause:

BTW, mrsracing, sorry if I sorta highjacked your thread:cheers:

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The black bulb (don't know proper name for it) in the bottom of the master cylinder. Should this "bulb" move up and down? I have the assembly apart and when I squeeze the handle it doesn't move. I'm working today on it to see what I can come up with. I'm going to take the caliper off again and see what everything else looks like.

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The black bulb (don't know proper name for it) in the bottom of the master cylinder. Should this "bulb" move up and down? I have the assembly apart and when I squeeze the handle it doesn't move. I'm working today on it to see what I can come up with. I'm going to take the caliper off again and see what everything else looks like.

Hmmm, it's been a while since I've looked at a master cylinder and I've never taken the one on my KX250 apart. Could you post a pic of the parts in question?

There should be a spring connected to the plunger and it will typically be enveloped by a rubber sleeve at one end. That's where your brake lever will push the metal center. It should move back and forth at the bottom of your master cylinder. That's what compresses the fluid to move your caliper's piston and finally, the brake pad against the rotor.

Karl

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Excellent! What parts in the master cylinder did you replace, Hammer?

Karl

It's the internals, i.e. the plunger thing with the spring and black rubber gromets, that goes inside thew master. I didn't replace any parts that connect to the lever, as they were in good shape. I replaced the pads with DP MX Pro's..next I'll replace the stock brake line with a Galfer braided line.

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It's the internals, i.e. the plunger thing with the spring and black rubber gromets, that goes inside thew master. I didn't replace any parts that connect to the lever, as they were in good shape. I replaced the pads with DP MX Pro's..next I'll replace the stock brake line with a Galfer braided line.

Greg,

Very good! So it was the plunger after all. Was it gelled up and sticky? That's how mine was. It means that it's seen some moisture.

The inside of the reservoir of mine was a bit corroded, too. I can tell you a fix for that so that you don't have to meticulously scrape and then sand all the crud out.

For swimming pools, there's an acid and I can't remember what the type was, but I don't think it was hydrochloric. I think it was sulfuric. Anyway, I dipped my reservoir in a bowl of it for a minute or two and it ate the corroded areas without touching the good metal. I've also used that treatment for a lawnmower carb that was left out in the rain. Better living through chemistry! :applause:

Karl

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Kargo, mine looked pretty good, so I didn't have to anything but replace the parts. Now as for some of the other parts on the bike, welp, that's another story, and needs a completely new thread..lol

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Kargo, mine looked pretty good, so I didn't have to anything but replace the parts. Now as for some of the other parts on the bike, welp, that's another story, and needs a completely new thread..lol

Greg, I'm with ya, bud. Been there, done that, got the receipts!

Karl

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