unclejemima wrote:So, I'm going to be converting my tadpole trike to electric real quick...only problem it has 120mm dropouts, and a SRAM 3spd internal hub gears...and no front de-railer.
The 120mm drop out is no prob, as its just a steel frame, so I'm going to just bend the frame to 135mm.
It appears that I probably cant put a rear de-railer on the back either, becuause it does not look like my bike has the proper mounting brackets on the back?
Those are very ordinary front opening horizontal dropouts. To fit your trike with a derailleur, you just need to get one with an integral hanger claw. They are cheap and easy to find.
If you want to install a nice quality derailleur instead of the cheap kinds that have integrated hanger claws as an option, you'll need an adapter claw. You bolt the claw onto the frame, and attach any bolt-on derailleur to it.
Do I need any gears? I guess if I go DD hub, I can still pedal until the speeds get stupid fast...
It borders on insanity to consider going fast on that trike. It's set up entirely wrong for fast travel. Too high, too narrow, can't lean into a turn. The thing will throw you right onto your head the first time you try to turn at 20mph. What you have there is a weird grandpa trike-- keep safe by limiting yourself to weird grandpa speeds.
Are there any electric hub motors with a internal gear system, or CVT?
The SRAM Sparc, now long out of production, was a 5 speed internal gearhub with two small electric motors built in. It was lightweight, but not very powerful (250W), and it had a top speed of around 16mph. That's more than fast enough for your deathtrap, but acceleration and climbing would not be very impressive.