Its been way too long from my switch from Engg student to biz owner .. can you help me out with this?(adsbygoogle = window.adsbygoogle || []).push({});

If I haven't given enough info below - the bike is a 2009 KTM 690 SMC.

I'm trying to figure out the instantaneous torque required to wheelie my bike in order to develop gearing proper to roll on 2nd/3rd gear wheelies.

In first - it will wheelie after 4k rpm with ease. Bike makes 63hp @ 7500, 47 lb*ft tq @ 5900. At 4k, its around 40 ft lb. With the gearing - 1st gear is 2.5:1, and final drive is 2.625:1. So first gear peak tq is 328 lb ft assuming no drive train losses.

Bike weighs 320lbs, I'm guessing CoG is 24" high. I weigh 180 with gear, my CoG on bike would be about 48" high. So together - roughly 30" high you have 500lbs CoG.

Wheel diameter is 24.56" - so from center of wheel to CoG(total) is 24" across, and 18" higher.

From this can you calculate the req'd tq to wheelie and show me how you did the calculations?

Thanks a bunch!

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# Tq required to wheelie

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