Front Brake is Soft - Honda RC51 Forum : RC51 Motorcycle Forums
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post #1 of 4 (permalink) Old 05-28-2016, 06:36 AM Thread Starter
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Front Brake is Soft

Good Morning,
This past winter I replaced the front brake pads and flushed the front brake system with Motul RF600 DOT 4 fluid. All was well.

After about 200 miles the front brake was getting soft despite the lever adjustment at 1. I bleed the front brakes again and all was well.

Now after another 200 miles they are getting soft again. I will bleed them again.

I see no leakage and the fluid level is at the normal level.

Do you think the master cylinder needs rebuilding? Is there a kit.

I appreciate any suggestions.



PS I have a 2004, completely stock and would like to keep it stock.
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post #2 of 4 (permalink) Old 05-28-2016, 10:04 AM
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It's likely the caliper piston seals. Lots of reports of such on the RC51. Evidence of a slow leak can be observed by pulling the pads out of the caliper and looking for moisture or excessive brake dust buildup. Do all of them.

Last edited by kwtoxman; 05-28-2016 at 10:14 AM.
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post #3 of 4 (permalink) Old 07-21-2016, 08:07 PM Thread Starter
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I want to end the story. I checked the calipers, they were dry. I purchased a rebuild kit for the master cylinder ($35) and the brakes have been fine for the past two weeks. Found dirt and the main piston seal in the master cylinder looked worn.

Thank you

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post #4 of 4 (permalink) Old 07-22-2016, 09:13 AM
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got my m/c rebuild and the brakes are still actting up. well the lever is. so i got a brembo m/c iam going to try. wish i had the same luck you did with your rebuild kit

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