This is the rear shock from my 2011 ZX-10R race bike. I used it for the last 2 races of the 2012 season. It is the factory shock, but it has a RaceTech spring installed on it and the valving has also been tuned by Traxxion Dynamics to greatly improve the rebound and compression dampening. This shock performs very close to an aftermarket shock at a small fraction of the cost. The spring is the proper rate for me, and I weigh 175 lbs without gear. It should be a good fit for anyone near that weight for track use and would be a good fit for a heavier person for street use. I have put over $400 of work and parts into this shock. The work was performed towards the end of last year so this shock still has fresh oil in it, which makes a big difference. Often times the stock shock is never serviced and that alone can cause serious suspension problems.
The stock spring on the 2011-2013 ZX-10Rs is very weak. Just changing the spring alone makes a world of difference in getting the bike to hold a line around a turn. However, it still lacks enough rebound dampening. The tuning Traxxion Dynamics performed on the shock cured that problem. The shock now performs well enough to be used on a racetrack. Want to know how effective this shock is: I won the National championship with this shock in WERA Open Superstock, beating a lot of people with Ohlins suspension. I dropped my lap times by 3 seconds at Road Atlanta after switching to this shock from the completely stock shock.
Race Tech spring = 11.6kg-114N, Tested/Verified By Traxxion to be 650lb spring
Traxxion Dynamics ReValve = Compression/Rebound Tuning, Shock Tested On Dyno, Fresh shock oil