Hello again Thank you for your comments. Very helpfull. Dirk, you are right, I was thinking on 5 mts full turn, 2,5 mts radius... my mistake and my bad english. :). Anyway, very good news for me. Jürgen, my inseam height is about 84 cm, wich I suppose will be enough to a 26" front... well, at least it works for a thinner, low profile tire (1"95), bus I want to use a "fat" one (2"0 low pressure). Why? because "Smooth road" is almost an unknown concept in Portugal... Sometimes it would be better riding off-road. A set of 20" wheels (as I have on my trike) can be very uncomfortable above 30 Kmts/h, I think a set of 26" ones will be much better, as I want to build a rigid frame. The measures I've been taking yesterday were not conclusive; I'm afraid I will have to raise the BB about 2"or so to use a 26" front - Is it possible without compromising the overall performance (stability)? I suppose there must be some kind of relationship between the horizontal distance between the pivot, contact path and BB. I just don't want to use a 24" front because in Portugal there are very few tire types to choose to this size. One question: how faster a python can be? (average and top speed). And did anyone found any relation between the total weight (bike+rider) and the maximum speed? Thank you very much, Jaime Alexandre