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Author Topic: Replacement Caliper?  (Read 1599 times)

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NJ750K1

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Replacement Caliper?
« on: July 10, 2006, 07:47:14 AM »
On my K1 CB750, the front brake caliper is frozen (piston stuck in caliper). I've soaked it in penetrating fluid, tried putting a screw into the pad and pulling it, and tried blasting it out with a compressor- to no avail. My air compressor tops out at 120psi. Would a more powerful compressor make a difference? Are there other options such as machining out and replacing the piston that I can explore? If all else fails, is there an aftermarket caliper that I can put on?

Also, I've got a set of tires on that are about five years old. Does the compound start to go bad? I've got them inflated properly, and it seems like the back tire locks up very easily when I hit the rear brake hard (compensating for no front brake). I've been driving a car with very good braking characteristics for the past couple of years, so let me know if I'm just spoiled and it's normal to be able to lock that back tire up, or if the tire is past it's prime.
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Offline csendker

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Re: Replacement Caliper?
« Reply #1 on: July 10, 2006, 07:54:09 AM »
Try using a grease gun - unscrew the zerk fitting from the end of the gun and thread it gently into the port for the brake hose.  They're not the same thread, but close enough to get a turn or two in it.  Then pump up the grease gun to pressurize the piston.  Worked for me.  Otherwise, I've picked up a spare or two used ones off e-buy, or see if elcheepo has anything, he's listing K1 parts --> http://www.anubiscycle.com/
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Offline Mark M

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Re: Replacement Caliper?
« Reply #2 on: July 10, 2006, 08:03:55 AM »
I find pushing in with a G clamp to break the seal, the piston will normally be partly extended from the back of the caliper. Then hook it back up to the master cylinder and pump it out, with some old fluid as it will go everywhere when the piston pops out.

 
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Replacement Caliper?
« Reply #3 on: July 10, 2006, 09:44:47 AM »
The grease gun was my last resort and it worked amazing well. It was very easy. Air compressor at 120 did nothing. If it had worked it could have sent a high speed projectile when it popped.   
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Offline csendker

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Re: Replacement Caliper?
« Reply #4 on: July 10, 2006, 01:04:41 PM »
Probably because grease is not very compressible... ;)
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NJ750K1

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Re: Replacement Caliper?
« Reply #5 on: July 10, 2006, 06:35:39 PM »
Just got home from work and tried the grease gun and it worked!  :o

Thanks for the help.
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Gabus

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Re: Replacement Caliper?
« Reply #6 on: July 11, 2006, 10:15:01 AM »
Your caliper question was very timely for me too, had read about the grease gun method before but didn't like the idea of screwing something of the wrong thread into a caliper.
Picture says it all..will never even try any other method.

« Last Edit: July 11, 2006, 10:28:06 AM by Gabus »
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