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Hi Everyone,

I've searched the forums, but no one seems to have my problem. The front brakes seem fine, but after driving for 10-30kms the front brakes start to drag, slowly getting worse until eventually they lock. From when i notice the drag to lock could be no more than 500m, at which point the bike won't move anywhere. I fix this by releasing some pressure out of the bleed valve from one of the calipers (i've always done the left, but imagine the right would work as well).

I've bled the brakes completely, where heaps of brown muck came out, but now the fluid is nice and clean. A friend told me it might be the lower float pin (name?) as its actually brass instead of steel, and wears down faster, but if it was jammed on the float, releasing the pressure shouldn't help?

Any ideas??

Matt
 

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Check the owners forum for your model Honda.
 

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Sounds like the piston is not returning due to dirt or rust, maybe your pads have worn too much which would of caused the piston to come out too far
 

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Although your machine is smaller the same brake issues do present no matter what the engine size. What follows are a few links to brake related problems and there possible fixes. Note: do not pay any attention to the "LBS" or Linked Brake System comments as your machine does not include this technology. But the basic hydraulic operation and commentary will apply.

I'd guess that your dealing with a seized caliper piston issue. And so the calipers need to be torn down and cleaned and rebuilt. This would include (while your there) new piston seals and the like. Kits are available to do this. Also ensure that the machined grooves the seals live in are cleaned of the hard particulate ( "mung" as I call it) so that the new seals work correctly. It's not about the old seals leaking, it's about the seals being able to "rock back and forth a bit" which allows for the seal to pull the piston away from the brake disc just enough to disengage the brake pads from the disc. Also ensure the pistons are clean and do not contain any grit/grime on there outer surfaces that ;make contact with the new seals.

A secondary issue might also be a plugged "return port" in the mastercylinder. This small port allows the brake fluid to return to the MC when the lever is released. There are two posts in the MC..the larger one feeds the system..the smaller allows the fluid to return to the MC. If the fluid can not return then the brake lever pressure stays on the system and the brakes remain in the applied mode. As your fluid was dirty this is possibly one thing to look at also.

Here are the links:
http://www.cbrxx.com/suspension-tires-wheels-brakes/9260-put-new-brake-pads-front-right-caliper-now-rubs.html

http://www.cbrxx.com/suspension-tires-wheels-brakes/11622-caliper-repair-kit.html

http://www.cbrxx.com/suspension-tires-wheels-brakes/20051-problem-front-wheel-brake-wits-end.html

http://www.cbrxx.com/suspension-tires-wheels-brakes/14992-check-out.html

http://www.cbrxx.com/suspension-tires-wheels-brakes/7556-drag-rear-front-left-brakes.html


There are more posts on this topic if you do a search for them.

Tony
 

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just do it
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:door:Be Nice
could be a future xx candidate.
 

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:door:Be Nice
could be a future xx candidate.
I'm sure the members there know more about that bike than here. Inspite of being a Honda.
 
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