These are the third generation design of our wildly popular 2WDW ZX6R Velocity Stacks that we developed a few years ago while building several engines for club level and Moto America racers alike! We have updated the design to utilize OEM-style rubber, which makes installation MUCH simpler than previous designs AND allowed us to further reduce the cost of these velocity stacks through mass production with our friends over at TST Industries! Installation is now just a simple as removing and replacing the OEM velocity stacks.
We were unhappy with the performance of the other velocity stacks on the market for these bikes. They either provided significant top end gains at the cost of equivalent midrange losses, OR they would provide decent mid range gains with virtually no top end performance improvements. Our velocity stacks are designed to offer the best of both worlds! With proper ECU mapping to match, you'll pick up 8-10hp at the very top of the RPM range with minimal midrange losses AND a much smoother power curve all the way to 15K RPMs.
NOTE: We do NOT recommend the use of ANY aftermarket velocity stacks on the 24+ ZX6Rs when the stock header is still installed. The new Euro 5 header is a MASSIVE restriction on the updated 24+ models, and using ANY shorter aftermarket velocity stacks will result in a MUCH larger bottom end and midrange performance LOSS when the stock header is still installed. Aftermarket velocity stacks should only EVER be used on 24+ ZX6Rs AFTER a full exhaust system is installed and the stock header has been replaced with a proper, high performance header.
NOTE: The above information does NOT apply to the 09-23 ZX6Rs, ONLY the 24+ models! The 09-23 ZX6R stock header flows MASSIVELY better than the newer, more restricted, Euro 5 design.
As always, if you have any questions, don't hesitate to send us an email at support@2wheeldynoworks.com. We're always happy to help!