Build of Recumbent with RS 35cc

This is the jackshaft where the human power and engine power are combined. The two outer sprockets are welded together and welded to the shaft. The inner sprocket is screwed to a freewheel--this sprocket is driven from the engine, the freewheel allows the bike to be pedaled with the engine stopped. The middle sprocket is driven by human power. The outer sprocket sends both power sources to the rear wheel.

I used a BMX style freewheel which is very noisy. The whole assembly is kinda heavy. So eventually I would like to improve this part. Are there other types of freewheels that are not so noisy. I intend to ride with the motor off a lot and this noise will start to wear on my nerves.
10Jackshaft_2.jpg


A Sturmey-Archer 3-speed hub is used as a mid drive to help route the chain under the engine and to provides 3 pedaling speeds.
11MidDrive.jpg
 
Lee...Keep on going! It looks like you are doing an excellent job. While I'm following your build, my mind takes me to my garage and the smell and taste of every motorized bike and trike I've ever put together. And, I agree that you sure chose the right engine. Good Luck.

Patrick
 
I like torsion bar suspension because I can make it myself. The rear suspension is the most unusual part of the bike, not better than typical coil springs, just different. It uses two 5/16 dia by 20 inch long 8620 steel bars.
12T-Bar-Assem.jpg


The torsion bars are inserted into the top tube. The push rods were made long. After its done and I ride it, they can be shortened to adjust the ride height. The torsion bars can be shortened to stiffen the suspension. The lever arms can be cut off and replaced with loner arms to make the suspension softer. Next job is the seat.
13RearSuspension.jpg
 
I'm out here and following along Lee, checking in from time to time, liking what I see a lot! DIY frame work, drive train, suspension, you're getting it done and thinking for yourself outside the box. Kudos so far, heck if we lived closer and I'd be looking over your shoulder checking in, lol.

Seriously, nice work, good to see some from-scratch innovation again, looking forward to all the steps to completion.

PS
frame builder near me packs tubes with aquarium sand and caps them before bending, claims they don't kink that way.
 
I've got mirrors on my handle bars to help see behind me. As for the conduit benders using a 1 1/4 inch hand bender with a kicker on the shoe on heated 1 inch ridged can be done without collapsing the pipe if you're a tall and large built person. Otherwise you'll need a multi shoe mechanical bender. If you know how to calculate bending radius' and mark your pipe you could do hicky style bending with a conduit hand bender.
 
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I've got mirrors on my handle bars to help see behind me. As for the conduit benders using a 1 1/4 hand bender with a kicker on the shoe on heated ridged can be done without collapsing the pipe if you're a tall and large built person. Otherwise you'll need a multi shoe mechanical bender. If you know how to calculate bending radius' and mark your pipe you could do hicky style bending with a conduit hand bender.
 
I am making the seat frame from 3/16 dia 8620 steel rod. Here, I have two bent sections. I am taking a lot of care to trim and line them up to be symmetric about a centerline. I have built seats like this before and they tended to be lopsided. By being real accurate at the start, I hope to get better results.
14FlatSeatFrame.jpg


Some of the cross bars are welded in place and it is ready for next bend.
15SeatFrameLaterals.jpg


After the last bend, I added a mounting frame made from 1/2 square by .035 wall 4130 tube. Then supports as needed. There will be another bend and more supports, but I need to try this to see how it feels before moving up the frame.
16MountedSeatFrame.jpg


Here's how it looks so far. Next I will make two seat pads.
17CurrentProgress.jpg


Thanks for following along and leaving your comments. Those are both good techniques for tube bending. I will keep in mind in case I ever try this again.
 
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After 30 years of electrical work I got pretty good at it. What kinds of welds are you using? Every thing is looking good so far. What is the bike going be used for? (Around town, long trips or shows).
 
Sometimes I think I am building this just for sake of building it. I try to do a fairly good job for a home built bike, but I don't have the artistic skills or patience to make a show bike. I expect to be using it for long rides. Part of the riding will be on bike trails where the motor needs to be turned off.

I made the seat pans from 1/8 hardboard and used 10-32 carriage bolts to attach them to the frame. I found these foam seat cushions at a Meanards store. I'll give them a try for seat cushions.
18SeatPan.jpg


Here's the completed seat.
19Seat.jpg


I made a temporary rear brake cable and took it out for a ride. It handles and tracks real well, but needs a little front end weight to improve very low speed response.
20FirstRide.jpg


I am starting to work on an engine cradle and waiting for shifter/brake levers so I can work on those.
 
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