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Old 04-03-19, 12:16 PM
  #13  
redlude97
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Originally Posted by TimothyH
Looking for a gut check. Help me out.

I'm probably going to order the flat mount Shimano version of the Hope RX4 four piston calipers.

Reference: https://www.hopetech.com/products/br...d/rx4-caliper/

These will replace RS805 calipers and be used with existing R785 levers. I'm hoping for better feel and less lever travel. Reviews seem pretty positive.

New wheels with centerlock hubs are being built. The old wheels are six bolt and so new rotors are on order. With new wheels and rotors I feel like this is the time to also do the calipers.

Are pads readily available?
Anyone have fitment issues?
Are there any criticisms of these parts?
Is there something better?

What am I missing? What other questions should I be asking?


-Tim-
interested to hear if this actually ends up being the case. The RX4 uses a 16/14mm piston combo and the RS805 uses a 21mm piston, which equates to 1420mm^2 vs 1385mm^2 surface area per side. Since the lever reservoir chamber piston isn't changing sizes this should increase the lever travel while increasing pad force slightly. I would have probably liked to see 14mm all around or a 15/14mm combo.
Edit: Got my dimensions wrong, the shimano caliper uses 22mm pistons for a SA of 1520mm^2, so the hopes should decrease lever travel and hopefully the decreased pad force is balanced by the better presure distribution on the larger pad.

Last edited by redlude97; 04-03-19 at 01:07 PM.
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