Originally Posted by Aeroplane

Riding the conversion with 170's, this technique is bomber. Instead of leaning the whole bike, you just put your body where it would be if you leaned, and leave the bike standing up.

What I would do, to see if you need new (shorter) cranks, is ride around on them and see how easily you can hit the pedals to the ground. If it's super easy, pony up. If it's nigh impossible, you'll probably be fine with the existing cranks.