Both 2 and 4 stroke. I will tell you if you race the Cat 90 removing the governor is a good bit faster than stock but the inexpensive replacement variators have completely different angles on the face and will outrun a bike with a stock unrestricted variator by a bunch on takeoff and midrange like maybe 2-5bike lengths in the first 75 feet and out of every low speed turn. I'd recommend this under $100 mod to even trailriders as we get a lot more grip from the perf variator and dont chuck belts even on our 90cc Cat stroker dragbike. The stock one doesnt let the bike actually be in the lowest gearing ratio nor the highest gearing possible in the clutching trust me I know we used the stock ones for 2 years. Now Happy [img]i/expressions/face-icon-small-smile.gif[/img]

 

looks like I got some work to do.