I have a set of stock CBR1000 forks that have the Penske piston kit installed. The kit was installed by Scotty Ryan with Trackside Suspension and Engineering(full rebuild was about $450) The spring rate is a 1.075 and is suitable for someone between 180-200 lbs. This is an awesome upgrade from stock and will be perfect for any racer or trackday enthusiast. These cartridges should fit Honda CBR1000 2008-2011. Six one eight 52zero eight040
I only know that they fit Honda cbr1000 2008-2011 Honda changed the fork in 2012 and I don’t think they will work