SimpleSimon
Active Member
My neighbor (to whom I sold a motorized bike a couple of months ago), has run into some difficulties recently. He's a mechanic, auto air-conditioning specialist, and does computer repair and custom systems fabrication as a side-line. Last week he had a hoist in the shop fail, dropping a 60 passenger school bus on his right leg. Amazingly, no bones were broken, but all of the ligaments in his knee were ripped loose.
So, he can't ride the bike I sold him for a while, but he has become addicted to getting out into the wind. He has asked me to design for him a tadpole recumbent he can build in his shop (VERY well equipped), and after discussion of the legal issues here, we have decided to go electric for the power system, but a tad different than most to keep johnny law happy. He has just gotten a temporary handicapped placard for his pickup, and the accompanying ID card, so he can qualify for use of a "mobility impaired" scooter. He goes to the same doctor I do, who is perfectly willing to write a prescription letter for the trike.
It will be powered by two 350 watt hub motors in 20 inch front wheels to begin with, and with the intention to add a rack-mounted GEBE drive at the rear later. This way, he can stealth around in electric mode, and eventually add gas power for longer distance runs out to the lake, which he does regularly to go fishing.
As drawn, the picture shows the bare bones of the frame. He wants rear suspension, so I crunched some numbers, and it appears to me that for simplicities sake the best option is the horizontal rear mono-shock approach. Keep in mind, this is intended for a vehicle with a maximum speed of 30 mph. He has tried and does not like side grip tadpole steering, so it will utilize more conventional steering geometry.
Specs are:
Wheelbase length: 48.5 inches
Wheelbase width: 26 inches
Overall length: 88 inches
Overall width: 30 inches
Steering geometry: Full Ackerman, zero point steering at 15 degrees.
The picture is just the bare bones at this point. I have wire-framed the seat position, which will be adjustable for angle of inclination. The forward pedal boom is adjustable, with an X seam range of 35 to 44 inches.
He tells me that he'll have the main boom bent, suspension pin for the rear triangle in place, and the cross boom for the front suspension done next week. After that it is a matter of waiting for his parts orders to come in, and getting it all assembled.
Comments, suggestions, critiques are solicited.
So, he can't ride the bike I sold him for a while, but he has become addicted to getting out into the wind. He has asked me to design for him a tadpole recumbent he can build in his shop (VERY well equipped), and after discussion of the legal issues here, we have decided to go electric for the power system, but a tad different than most to keep johnny law happy. He has just gotten a temporary handicapped placard for his pickup, and the accompanying ID card, so he can qualify for use of a "mobility impaired" scooter. He goes to the same doctor I do, who is perfectly willing to write a prescription letter for the trike.
It will be powered by two 350 watt hub motors in 20 inch front wheels to begin with, and with the intention to add a rack-mounted GEBE drive at the rear later. This way, he can stealth around in electric mode, and eventually add gas power for longer distance runs out to the lake, which he does regularly to go fishing.
As drawn, the picture shows the bare bones of the frame. He wants rear suspension, so I crunched some numbers, and it appears to me that for simplicities sake the best option is the horizontal rear mono-shock approach. Keep in mind, this is intended for a vehicle with a maximum speed of 30 mph. He has tried and does not like side grip tadpole steering, so it will utilize more conventional steering geometry.
Specs are:
Wheelbase length: 48.5 inches
Wheelbase width: 26 inches
Overall length: 88 inches
Overall width: 30 inches
Steering geometry: Full Ackerman, zero point steering at 15 degrees.
The picture is just the bare bones at this point. I have wire-framed the seat position, which will be adjustable for angle of inclination. The forward pedal boom is adjustable, with an X seam range of 35 to 44 inches.
He tells me that he'll have the main boom bent, suspension pin for the rear triangle in place, and the cross boom for the front suspension done next week. After that it is a matter of waiting for his parts orders to come in, and getting it all assembled.
Comments, suggestions, critiques are solicited.