Two strokes, rev limiters, and gearing (Rok GP in this case)

I’m accustomed to non-rev limited gearing choices, including the option to overrev on the straights in order to have more aggressive gearing in the tight stuff. Is this also the way to think about gearing choices with a rev-limited two stroke - meaning that just depending upon the track and objectives it is common/advisable to just ‘ride the limiter’ for a bit of the straight or is that always going to be a bad choice? (and if so, the reason(s) why would be appreciated). Thanks!

Based on all of the onboard footage I’ve seen from Rok GP, those guys are begin to be on the limiter anywhere from 50-75% down the straight, depending on how slow the slowest corners are.

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Great idea to try looking at footage, and I even found a clip of a top driver with his Rok GP at the track I was at today, but honestly am having a hard time discerning exactly when the engine is tops out (all I hear brrrrrrrrrappppp, lol :grin:). It does seem like it, but not a very precise read by me.

I guess all I really need to know is whether I would damage the engine by running against the limiter for any reason, and I guess if not then it’s all up to preference…

It’s not a hard limiter, ignition timing just goes from 23 to 3deg advance at 14500 to 1500 so the engine just falls flat there and won’t pull anymore.

It’s a very mid-rangey engine too from all accounts, so gearing might be a tricky balancing act if you have a wide range of speeds to achieve.


Thanks Mark, that’s very helpful and specific. Looks like I’ll be adding a tooth or two to the rear sprocket.

At the risk of sounding like I’m stating the obvious… Start by selecting a gear that allows you to have a tolerable exit from the slowest corner on the track. Don’t gear for the longest straight, you’re not there long enough relative to the rest of the track.