wow, so many topics touched on here that im struggling with at the moment i'm not sure where to start.
you hit the nail on the head with the difficulty in getting a small wheel dh bike - i am currently looking at dh dual crown forks (marzocchi juniors) but they have a 20mm "through axel" - i worked out that my frame headset will take the forks no problem, is a straight fit so not too much bother there.i intended to keep the original frame i have as it has large triangle to fit my lipo's, i think you will find that unless you have the ability to break/remake battery packs (which you do you lucky swine) you won't find a suitable dh frame to mount with. secondly on that front dh frames are heavy!! most have the 20m through axel on the forks too.im not sure what they have on the back but would be surprised if a hubmotor would drop straight in? dh frame and forks are a heavy combination - i think too heavy for a hub to power well, although that said you may get an xc frame with good travel (4") that would do the job "giant reign" bike for example.
Anyway after looking into it i thought that i would keep my limited travel frame and go with the marzocchi forks, however after speaking to a bike shop today they gave me good news and bad news.
good news was that they could build me a front 20" wheel with the rims i want (halo sas combat 36hole) and use a 20mm through axel hub allowing me to drop it straight on the marzocchi's and use my disk no problem. i had planned on getting a rim only again 36h and sending it to mark to lace in my puma.
Bad news is the guy at the bike shop told me that he thought although it could be done, really the marzocchi's need a 26" wheel (maybe 24") as if you run 20"s once under load it would be very hard work for the frame headset post not to snap once the fork travel kicked in
its difficult to marry parts from various bikes, thats even before you consider the electrics!!
i see - i cannot wait to hear how your bike runs on knoxie's lipo's as i said they really can put out some power and seeing your hill climb at 20a 35a should be outstanding to the point of you struggling to keep the front end on the floor!!
wondered about your dual crowns also - are they 1 1/8" steerer tube?
my bike is currently in bits and although i want a similair setup to ypedals thoughts i'd really like to stick with 20's - i find that the clearence issue is totally gone with my shortened crank and im really happy with the way it pedals too so no problem there.Also the torque on the puma is also very acceptable so you may find that you are able to go back to 20's too with the extra power?
An exciting time - cannot wait to see how evryone's bikes turn out - im still looking for the dream bike like Ypedal so i'll get some pics up once it's built, then i'll be looking to you guys for some help in powering it right