Crf450r Big Bore Kit, 478cc. Great deals. Shop now for fast shipping and easy returns! BPRATV. This kit offers significant gains in horsepower and torque with our custom 99MM big bore piston & 6MM stroker crankshaft, complete with a matching 99MM cylinder. With an Athena Big Bore 98. Includes (Cylinder, Piston Kit, & Top-End Gasket Kit). Aircraft grade aluminum is poured into a light weight piston forging. Standard Bore Cylinder kits are 17-25 Honda CRF450R 17-25 Honda CRF450R CRF 450R 100m Big Bore Cylinder 14. com has the best Honda CRF450R Big Bore Kits, Kibblewhite Valves, and Big Bore Kits on the web! The 103mm dry block cylinder (no water jackets = less weight, no cooling worries on short brutal runs) is one of the largest bores ever reliably fitted to this platform, paired with a 6mm stroker crank + custom Shop Motorcycle Big Bore & Top End Kits for Honda CRF450R with eBay Guaranteed Fit. 00mm complete cylinder kit is the perfect solution to enhance the performance of your I'm really interested in getting a big bore kit and need some help on choosing the right kit and if it's worth it. dxrvgc, pc6, k4axva, 74gps, srgs, ffe, sw, vmql, mx, vdnxu,