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Re:master cylinder bore size question.
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TOPIC: Re:master cylinder bore size question.
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jd750ace (User)
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Gender: Male jd750ace Location: Waxahachie Texas Birthdate: 1969-10-30
Re:master cylinder bore size question. 4 Years ago  
http://www.vintagebrake.com/mastercylinder.htm

Settle down for reading and math buddy! Give this a good going over and see which will give you the better ratio, but I'm willing to bet the smaller bore is a better feel. Too large of a master cylinder gives that "wooden" feel. If you ever feel a wooden brake you'll understand that term immediately.

My XS had a crappy front brake before I went from a 13mm down to an 11mm master cylinde. Now it's great.
 
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Last Edit: 2014/02/03 21:56 By jd750ace.
 
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zip1700 (User)
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Re:master cylinder bore size question. 1 Year, 4 Months ago  
I know this is an old thread but It is an important question. Believe it or not, it works in reverse to our thinking. A 14mm 0r 9/16 works best for two four piston calipers, obviously, because it is used for most of those applications. A smaller orifice will have a feeling of more pressure, or a touchy break that is easily locked up. I did this when I bought a front brake cylinder for my Warrior and went with a Arlin Ness front break set up. Had to do a slight ream at a shop so the brake was not so quick and touchy causing lockup.
 
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BOBJO (User)
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Re:master cylinder bore size question. 9 Months ago  
HI , I have a 2002 RS I have installed a New Single PM 6 piston front caliper and am using the stock RS 2002 front MC.
Front rotor is a stock RS OD ,floating one from RC.
Front wheel is a 19 inch.
Brake Feel is " Hard as a Rock, You have to really squeeze hard to get bike to slow down. Thinking of trying to find a 12 or 13 mm front MC. Any suggestions ?
Thanks
 
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texasscott1 (User)
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Re:master cylinder bore size question. 8 Months, 4 Weeks ago  
Look a couple of posts up at the link JD provided. It doesn't list any 6 piston calipers so you would have to calculate the total area of the pistons and divide that by the area of the different size master cylinders until you came up with a ratio of about 25:1.
 
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#1012419
HotRodStar (User)
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Re:master cylinder bore size question. 8 Months, 4 Weeks ago  
BOBJO wrote:
HI , I have a 2002 RS I have installed a New Single PM 6 piston front caliper and am using the stock RS 2002 front MC.
Front rotor is a stock RS OD ,floating one from RC.
Front wheel is a 19 inch.
Brake Feel is " Hard as a Rock, You have to really squeeze hard to get bike to slow down. Thinking of trying to find a 12 or 13 mm front MC. Any suggestions ?
Thanks


Try to pick up an 04 or newer 14mm MC for cheap and try it first. I am running 2 6 piston calipers on my 02. I actually had to step up in size to the early 15mm as mine was WAY to touchy with the 14mm 04 and newer. Works much better now, but would still like to find one with a slightly larger bore to tone it down a bit more even.

Rod
 
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#1013451
NickJFerro (User)
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Re:master cylinder bore size question. 8 Months, 3 Weeks ago  
I have a 2000 XV1600 and my stock master cylinder has 5/8" stamped on it.
 
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BOBJO (User)
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Re:master cylinder bore size question. 5 Months, 4 Weeks ago  
Hi Frosty , What year are are your bikes ? I am looking for a 9/16 / 14 mm front master cyl.

Thanks
Bob
 
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BOBJO (User)
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Re:master cylinder bore size question. 5 Months, 4 Weeks ago  
Hi,
I would like to keep the MC stock as possible so I can still use the factory brake switch and mirrors.

Thanks
Bob
 
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