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Rupai
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Join Date: Jul 2012
Posts: 3

Front Disk Brake Busted After Collision

07/26/2012 11:03 PM

I had a minor collision with the motorcycle I was riding with and the front brake stopped working. What haopen is, my biker friend suddenly stoped and I hit his rare with the front of my bike. As a result I lost control and dropped the bike. The collission happen at an intersection while waiting for traffic in front to move. So the collision wasn't very hard at high speed. Anyway, after I lifted the bike, everything seemed fine no scratch nothing. The engine started and I could move to releive the traffic behind me. But right away I've noticed that the front disk brake was not working any more. Interesting part is that, the brake seems work while the bike is at halt. At stop the when I pull the brake lever I can feel the regular pressure like before. Its only when the bike starts to move there is no pressure when I pull the lever. As if there is no breake fluid. I checked for brake fluid leakage but in my untrained eye, I couldn't find any. Has anybody have any idea? Please help. I would like to fix it myself before going to a mechanic. By the way mine is a Harley davidson about 500 pound. But I believe, not sure though, that the front disk brake is not stock brake, as it was modified before it became mine. Thanks in advance.
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Pathfinder Tags: Front disk brake problem Motorcycle.
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lyn
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#1

Re: Front disk brake busted after collision

07/26/2012 11:40 PM

Get local, professional help.
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BDThompson
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Join Date: Jun 2006
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#2

Re: Front disk brake busted after collision

07/27/2012 2:03 AM

Let's change the scenario slightly.

If you knew someone who had an "untrained eye", would you trust them to correctly repair your motorcycle even if they had been told what was wrong?

As unfamiliar as you are with the machinery under you, please find a fully qualified mechanic to troubleshoot the problem and repair it. The lives of you and the people around you could depend upon it.
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Rupai
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Join Date: Jul 2012
Posts: 3
#4
In reply to #2

Re: Front disk brake busted after collision

07/27/2012 6:29 PM

Yes I would take pro help. My intention was to just see if its a minor issue that can be fixed by an untrained person, eg. a loose screw or things like that. Moreover, why not be a little more curious, so that life becomes fun. I love to learn new things and tinkering with machineries. But thank you anyway for your advice and concern and taking the time to post.
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charsley99
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#3

Re: Front Disk Brake Busted After Collision

07/27/2012 12:48 PM

Sounds like you may have pinched a metal tube to the calipers. As previously stated, get a qualified mechanic to check it out. 90 % of your breaking is with the front brakes, especially with a panic stop. Don't take chances with your neck or others.

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K_Fry
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#5

Re: Front Disk Brake Busted After Collision

07/28/2012 2:55 PM

If the brake works when stopped but not when moving, then it is likely that the disc has been slightly bent. Then the disc will knock back the caliper piston(s) with each revolution, causing a lot of travel at the brake lever to take up the gap.

The other obvious possibility is that there is air in the system (from the master cylinder being on its side) and this will make the first pull on the handle ineffective.

But this is the sort of problem that should be diagnosed and repaired by a professional. Do not ride the bike without a fully functioning front brake -- the rear brake cannot stop you quickly.

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bob c
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#6
In reply to #5

Re: Front Disk Brake Busted After Collision

07/28/2012 9:20 PM

That would be my guess from what I read. To test, put the front of the bike on a stand so the front wheel spins freely. Spin the wheel and watch for warpage, or bent rotor.

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brettj1au
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#7

Re: Front Disk Brake Busted After Collision

07/29/2012 3:04 AM

To me it sounds like the brake lever was squeezed when the bike was on it's side & put air into the system, some times pushing the pistons in the caliper all the way back into the caliper can push the air back into the master cylinder reservoir from the line. Then you pump the lever a couple of time to push them out, make sure you pump them out to normal operating position before trying to ride the bike. If that doesn't help & you are capable, I would suggest bleeding the brake system to get rid of any air. Make sure you top up the reservoir while bleeding so as not to add more air.

If that doesn't fix the problem seek assistance from some one experienced in bike brakes.
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brettj1au
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#8

Re: Front Disk Brake Busted After Collision

07/29/2012 3:30 AM

Just a note to add to my previous post when pushing the pistons in the calipers back be carefull as the fluid will leak from the reservoir if it is too full try to set handle bars in a position that allows the resevoir to sit as leval as posible . Also while working on brakes & useing brake fluid be carefull not to get the fluid onto your paint as it will destroy your paint ,wash it straight away with water if it does happen.
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xanasax
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Join Date: Dec 2010
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#9

Re: Front Disk Brake Busted After Collision

07/29/2012 10:25 AM

As Lyn said, get professional help, never try to repair brakes yourself, and never trust a friend to either, remember your life depends on your brakes, so call in a professional..!!!
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Envelope Guy
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Join Date: Mar 2011
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#10

Re: Front Disk Brake Busted After Collision

07/30/2012 9:30 AM

What you really should get is some professional riding instruction before you ride again.
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Rupai
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Join Date: Jul 2012
Posts: 3
#11

Re: Front Disk Brake Busted After Collision

08/05/2012 4:57 PM

Like some suggestion before, yes it was a dent in the disk. I took the bike to a mechanic, changed the disk and everything is fine. Thanks to everybody for their time and suggestions.
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Users who posted comments:

BDThompson (1); bob c (1); brettj1au (2); charsley99 (1); Envelope Guy (1); K_Fry (1); lyn (1); Rupai (2); xanasax (1)

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