Burris is pleased to announce the release of our new updated “Gen ll” XR stainless valve kit for the Yamaha YF200. Made in the U.S. of the high quality forged stainless steel on CNC machines to exacting tolerances and feature hard chrome plated 5.5 mm stems and hardened tips to insure long life and performance. The 26mm intakes are swirl polished (our experience has shown this size is adequate for current F200 applications) and the 24mm exhaust has a race flow stem relief for better flow and machined for 7 degree radiused locks. The Gen ll upgrades include longer valve stems to allow for more clearance between the guide and retainer at full lift and relocated lock grooves that reposition the retainer to give about 10% more seat and full open spring pressure without the use of shims. (For added insurance the kit comes with hardened steel wear caps for the stem tips.) The kit now includes the tried and proven XR valve springs to compliment the new Gen ll spring retainers which are now made from hard anodized, Teflon coated aluminum (versus chromoly for the Gen l). The lighter weight reduces the acceleration/inertia loads on the valve train and also allows for more rpm’s (approx. 300/400) without valve float. To compliment the longer valves, longer chromoly tubular push rods are supplied to correct the rocker arm geometry which in turn allows the valve to open closer to the .275” maximum lift than with the Gen l kit.

The Gen ll kits contain 2 ea of the following; valves, valve springs, retainers, locks, push rods, wear caps, spring shims and rocker stud spacer washers.

The new kit is a “bolt in” and only requires a slight resizing of the guides. No other machine work required!

                                           Pt # F21-415-10