Very cool project. I don’t think the electric bike links provided by the 1st answerer describe your enclosed, monocoque body at all.

Gang, he’s looking for something VERY streamlined!

I wouldn’t trust a suspension that was bolted on. I suggest you weld the critical pieces. Use bolts to mount the motor etc.

How about “raiding” an existing motorcycle design (and parts)? They’re proven and you could “cherry pick” to fit what you want.

Hydraulics are a problem. They require an HPU etc. And what if it sticks, leaks, or fails? Does the bike just fall over? Do you need a backup mechanism? Why not just go with a dry mechanism to begin with. Simple and reliable. Use an over-center approach to lock the side wheels down.

As for picking a place to build it, you could sink a lot of money in it and be disappointed if you’re not careful. The _design_ of the thing is probably best separated from the _fabrication_. Work out design details before you approach a fab shop. It’s expensive to change the design when something’s partly constructed.

To keep it light, I’d urge you to look at the newer lithium batteries instead of the heavy lead acids. Pound for pound, lithiums have 3.3 times the energy as lead acids (but then they’re 10x as expensive!). That weight savings will be important if your goal is 600 lbs.

Good power to weight ratio; it’ll be a rocket at 600 lbs!

You might find some parts at standard EV parts places, like KTA below. Since your goal is so light weight, you might find parts through the Electrathon gang (google it). The EAA (Electric Auto Assoc) could be useful (link below).

Thunderstruck Motors builds race level, electric bikes in Santa Rosa, Cal. They could be helpful with design, parts, and fab.

I like your basic ideas. I may have to try them out.