RC51 Brake Measurement Needed - Wrist Twisters
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post #1 of 4 Old 11-15-2015, 05:26 PM Thread Starter
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RC51 Brake Measurement Needed

Hi all,

People say my posts are sometimes too long winded. So. . .

Short Version:

Will someone please measure the horizontal distance on an RC51 front brake lever/master cylinder from the OUTSIDE (right side) of the bar clamp to the innermost end of the head of the banjo bolt?


Long Version:

I've been doing a bit of work on my '07 lately. After the new Power 3s solved my horrible handling problem, I figured the next thing should be working on my position. I've had Renthal Lows, but my really tall body and long arms made those not quite right.
As such, I got a pair of steel Emgo drag bars. The new position is magical. The only issue is that my brake master cylinder configuration won't allow me to rotate the brake lever down into a comfortable position because of interference with the top triple. I think a new brake with a remote M/C is the fix- probably a full RC51 setup. At any rate, I'm hoping someone can measure their RC51 lever/master cylinder and confirm for me that it'll help.
I measured my stock M/C setup, and found that the distance from the OUTSIDE of the clamp horizontally to the farthest edge of the banjo bolt on the inside of the M/C is 94mm.
For a brake to work, I think this distance will need to be 85mm or less.

Anyone able to measure this for me?


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post #2 of 4 Old 11-17-2015, 06:28 AM
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post #3 of 4 Old 11-20-2015, 12:40 PM
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The RC51 master is a conventional axial type, so the length is going to be more or less the same as the stocker. Plus, of course, it is misproportioned for the stock calipers, requiring the entire front brake setup to work properly.

An alternative is the master cylinder for any post 2004 CBR1000. It will be a radial which places the outlet right under the clamp, and takes up much less handlebar real estate. That is the setup I am using with the stock calipers and it works very well.


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post #4 of 4 Old 11-20-2015, 03:54 PM Thread Starter
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Thanks very much for the tip. Funnily enough, I researched a bit more (including some of your posts re: CBR1000 lever), eBay'd a $50 2007 CBR1000 radial M/C unit with a scratched up Chinese Pazzo lever replica, and got it all mounted up and whatnot last night. In ordering, I'd suspected that the actual lever portion of the Pazzo levers are universal, with only the "bases" being model specific. I also banked on the Chinese replicas being a carbon (not the fiber) copy of the real deal. Sure enough, I removed the Chinese lever from it's base on the CBR M/C and installed my current real Pazzo lever that I'd had installed on the stock M/C unit. I had to cut the lever adjustment spring a touch (the spring hole on the Chinese one was drilled a little deeper), but everything matched up well and I've still got matching Pazzo levers! As I assume you did, I fabbed up a different mount bracket for the reservoir.
I don't really feel a whole lot of difference in the braking action; so I guess it feels fine. At any rate, I got out for about an hour of riding today; might be the last one for a while, and it sure was a good one!

Thanks for the help today and the delayed help from your posts several years ago about levers, M/C bore/ratio/etc.

Until next time,

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