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Rear brake fade.

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What causes it and how do you fix it. I've never had the problem on a 250. Twice now on the 450. Yesterday coming down a 4-5 mile twisty steep fireroad they disapered again.

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👍 We have rear brakes?🤣

If your pads are still good, the first thing I'd do would be; replace the brake fluid and bleed the brakes.

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What does fluid,bleeding or air have to do with it? They work fine until they get really hot.Once cooled down they are back to normal. "Fade" not loss of brake all the time.different pads? Larger rotor?

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Brake fade occurs with over-heating of brakes from extended use. It might be worth your while to put on a rotor with more cooling lines and x-drilling on it. There are lots out there with far more cooling capacity than a stock, and I'm not sure about rear but I know they make oversize disc kits for the front. Also try a good set of pads, a softer pad will wear faster but will also stay sticky for longer whereas a hard pad will heat and just glaze immediately.

Fluid, bleeding and air shouldn't have anything to do with it as long as your brake feels strong coming on in the beginning and is just 'fading' away with use.

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What does fluid,bleeding or air have to do with it? They work fine until they get really hot.Once cooled down they are back to normal. "Fade" not loss of brake all the time.different pads? Larger rotor?

Sry must have misread your post.👍 I was thinking you meant all the time.

+1 on what Mulciber said.

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No prob james.

Mucilber: thanks for the info,I'll shoot ya some rep.So I did a little research,not sure if it pertains though.Honda threads: They say the master cylinder has a 2 seals and one of them is kinda week and fails.rebuild.Boiled brake fluid/use Motul 600 fluid with a higher boil temp and or softer pads.

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I haven't checked stallion, but I wouldn't be at all surprised to find the two are very similar or the same seeing as so many parts on all bikes are the same basic product. Now that you mention it the boiling fluid rings a bell too... Even on a normal basis brake fluid breaks down and loses it's effectiveness. So that makes good sense. I changed out all mine last year for that reason. You definitely don't need these kind of issues when you're running downhill for that long a stretch 👍 most uncool. Good luck and thanks.

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With new pads there is more material to soak up the heat before it fades.

There are pads with insulated backing that doesn´t transfer the heat into the caliper as bad.

Washing out the old brake fluid with fresh D.O.T. 5.1 raises the boiling point.

Remember, brake fluid is "hygroscopic" and draws moisture from the air, even through the M/C diaphragm with the cap on. New fluid twice a year makes wonders.

Removing the rear disc guard results in more airflow.

Or you could just brake with the front more:thumbsup: lol

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Had that happen to us last year, race motocross. Was using EBC Gold pads for most of season with no issues. Went to a track with very fast downhills & would lose BOTH brakes about 1/2 way through 2nd lap. After cooling down would be fine. They were still pretty new/thick pads. Tried lapping them, etc to get rid of glaze, no help. Rear rotor on KX250 was actually turning blue from trying to stop. Switched back to EBC red pads, no more problems. Had same problem same day, KX250 2 stroke & CRF250R, so don't think it is master cylinder issues. It did help with learning higher corner entry speed though!!!

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So check this out.Yesterday I go to the local Mom n' Pop Moto shop and wanted to get some new pads. I'm talking to the guy at the cash register as he's looking up the part number I'm picking his brain. He tries to sell me some 20.00 pads without ceramic backing.The young mechanic comes out and helps him out.I like this guy,He's pretty knowledgeable from other times I've talked to him.I told him I want the EBC red lable pads and would higher temp fluid work better. He suggest the pads first before changing fluid. So I go about ordering them but not sure if that's what I'm getting.So as I'm trying to make up my mind the guy at the counter goes about telling me that Higher temp synthetic fluid won't make a differance when the Owner comes out and the guy ask him why he thinks my break fades.Boss man goes on to say I'm either rideing the break, not using the front enough, or I have a bent Rotor and boiling fluid has nothing to do with it, as his shit don't stink.Well this kinda pissed me off as none of the above was true.If anything I might not be using enough front but prefer not to wash out in the sand or rock I was riding in. So at that point I said no Thank You I'll just order my parts online.So I'll wait till I need enough Items and order some where else.

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Jusr read a recent article about on of the top off rider and his brakes. He uses an extra brake pad on the caliper side to act as a heat sheild. There is no braking material on the pad just the metal portion

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I bled my rear brake on the -09 for the first time today. And I always preach to do it often...👍

The fluid was really dark, almost black. And there was black gunk in it.

Wish I would have done it sooner...

The pedal felt firmer afterwards.

A brake bleeder catch bottle is handy:

19-146_l.jpg

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Cool!what about a breast pump?

How did you know that that´s my area of expertize?

swing3.jpg

But the brake bleeder bottle is good, I only use it as a catch bottle. I don´t trust those checkvalves...

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