Join Date: Aug 2006
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I had a GP Mk2 19x20 before my RCS Corsa Corta and I loved it, but the brakes are pretty much either on or off. Advanced users only.
When switching masters, you always need to make sure you're using a compatible piston size. If you're sure the R1 master has the same diameter piston as the 675's, no problem switching. Using a 19x20 would also be OK, but you'd get better feel with a 19x18. That's why the RCS is so nice - there are tons of combinations available to change the ratio.