Author Topic: Brake Question  (Read 2139 times)

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Offline alan

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Brake Question
« on: April 17, 2013, 08:43:32 AM »
I have been having a strange problem with my KFX700 front brakes. I know this is a bike site but the master cylinder is the same except for dual calipers and a pressure sw for the brake lites.

So when I let it set the front brakes get pressure and lock up when the temp gets cooler it releases. I have totally replaced the brake fluid and bled the brakes at the calipers lots of times. DOT4 fluid. And still it gets locked up when the temp goes up. I have never had this problem on any disc brake system before.

Any Ideas?
Sand - Dirt - Dunes = Fun
       04- 700V - 01- KX500
        08 TeryX 2012 KX450F

Offline sandblaster

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Re: Brake Question
« Reply #1 on: April 17, 2013, 09:49:35 AM »
Hi Alan.
I have not seen that problem specifically but have you removed the calipers and pulled the pistons out?
It's amazing what you can find in these things and they are suppose to be spotlessly clean...
Same goes for the master cylinder.
If you haven't done this it might be a good place to start.
Also, what does your manufacture recommend for the fluid?
I'm assuming Dot 4 but it could make a difference.
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline fivehundo

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Re: Brake Question
« Reply #2 on: April 17, 2013, 12:04:52 PM »
I would check the compensator port (hole between reservoir and master cylinder bore) in the master cylinder, sounds plugged.

Offline sandblaster

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Re: Brake Question
« Reply #3 on: April 17, 2013, 12:13:27 PM »
You see, I didn't even know there was a compensator port on your bike... :-o
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline wierdo

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Re: Brake Question
« Reply #4 on: April 17, 2013, 12:30:13 PM »
use new brake fluid not stuff thats been opened and sitting on the shelf for ages. it absorbs moisture with time.

Offline alan

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Re: Brake Question
« Reply #5 on: April 17, 2013, 02:41:28 PM »
Yep compensator port! That must be it! Thanks guys! :-D :-D :-D :-o :-o
Sand - Dirt - Dunes = Fun
       04- 700V - 01- KX500
        08 TeryX 2012 KX450F