Rotax RPM 14000

Running Rotax Evo Sr and getting to 13200 rpm max on the straight right before the first corner. My gearing is good for the size track. Should I be hitting 14000 or does the performance drop over 13000?

I think for any engine, performance drops are going to happen at some point in the rpm band. The Real Question is how is it out of the Corners and does it still Pull all the way down the straight. If going up a Driven Tooth causes the rear to step out on corner exit, then you are close. If the Pull down the Straight is lacking, then maybe go up a tooth or two on the Driven sprocket. Its always a balance and can change with track layout, grip levels and driving style. You can always adjust your throttle application to compensate for rear grip (or lack of) on corner exit, but you cannot change your gear on track for straight line pull. You can change your line to roll off the corners for higher exit speed and allow you to run a lower driven gear and hit peak rpm. Just have to play with it and see what it does. Some of the fastest guys will be banging off the rev limiter at the end of the straight, while other fastest guys never touch it. See what makes you Fast and work from there.

It’s still pulling at the end of the straight and feels good all around so I’ll try a tooth up.

most probably gearing. In Australia we run a restrictor plate and I seldom get over 12000. Also don’t just mash the pedal on the final corner, feed it in slowly.

I’ll try a tooth up considering the straight is uphill. Is your restrictor in the exhaust pipe? I thought the evo allows you to mash the throttle unlike the pre-evo?

yeah in the exhaust. Nope you still have to feed it in gently.

Do consider track conditions have an impact on high RPM also. I normally hit 15900 at my local track, last week after some sandstorms the track condition was less than great, I barely reached 15k, just because I couldn’t carry so much speed through the last turn. A few days later after they ran a 60 minute rental endurance I’m hitting 15900 again.

That’s not a Rotax Max though I assume?

1 Like

Lol no, same would apply though just different numbers

1 Like

I’ll have to get use to being light on the pedal. I came from 4 cycle where you can hit it hard. You scared me for a second when you said 15,900 but I get what you mean, thank you

I can’t remember from whom I got this tip but it works for me.

Imagine your go pedal is a wet sponge, press on it as though you’re squeezing the water from it.

1 Like

As you can see HP drops off at 115002014_11_28_fact_sheet_rotax_125_max_evo-3graph

Interesting…so I shouldn’t be too concerned about not getting to 14,000 then. Thanks for sharing

1 Like

I think what you should be trying to find out is if others on the same gearing are getting more revs than you.

The short answer is yes, the engine should easily be able to go beyond 14000 rpm if geared and jetted properly. If you have uphills etc then all this throws in different combinations.

On my pre-evo rotax I can easily hit the limiter at 14200 so I see no reason why the evo can’t do the same at 14800.