I found a cheap Emoto G6 3000w scooter the other day. Came with SLAs which got hot when charging. Took them out and put in my 16s A123 9ah pack for some testing. Got 3400w peak and the weight reduction was huge. The scooter is now 180lbs or about the same weight my KE100 will be. I will have around 7kw peak on it, so it should have twice the performance (and 20mph higher top speed). Before I took the lead out, I rode it with my gf on the back. Performance was acceptable for city streets, though it didn't want to accelerate much from a low speed on a hill. I have no worries that my KE with 7kw, and 100lbs less weight will do just fine with my gf on the back. Of course, if I do get a battery capable of 30kw, that should be interesting!
One thing I noticed - the scooter doesn't use a contactor. With a controller shut down wire, it doesn't seem like it's needed, but not a bad safety.
Back to the KE - with the flipped swing arm, I decided to use the same suspension mount holes, which meant lowering it ~3". Seat height is looking like about 24" now! Enduro turned cruiser! Should be great for my frontal area reduction, and cornering. There should be just enough space for tire clearance, but if not I can raise the seat supports with some quick cutting and welding to make more room for the tire under suspension bottoming out. I should have the motor mounted this weekend. I picked up this $42 60v brushed controller. Reviews say it puts out 50-100amps or so. Not much functionality, but a cheap backup. I may also do a 2nd motor for ease of adding more of my small ebike battery. I just won't be able to power the same motor at the same time with both controllers.
http://www.ebay.com/itm/170937655932?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
Also got my RS232 - USB adapter for programming the Kelly controller. $3.24 on ebay, beats the $25 elsewhere!