Arthur? ............. or anyone else? What's the diff between HPK's and the GP4-RX like the one's in the below link as they seem near identical in price? 09-14 Yamaha R1 Brembo 130mm GP4-RX Nickel Radial Caliper Kit | eBay
HPK means High Performance Kit, with calipers you have CNC P4.30/34, CNC GP4-RX, M4, CNC GP4-RR and CNC P234 rear calipers, they are all HPK calipers.
Yep, 1,000.00 plus lines 60.00, plus T drive 500.00, plus master 300-2000.00, plus Ti fixings, bleeders, pinch bolts and banjos or so, adds up to some good stopping power at the front, but my good man, when you hit the brakes you KNOW where your money went...lol