BikeE recumbent full suspension, custom mid-drive

[A-DamW]

Hi all,

I've been slowly working on this BikeE recumbent full suspension ride I picked up a year ago for a good price.

 

[A-DamW]

I replaced the leaking stock air shock with a cheepo steel spring one I had laying around.

Had to do some light machining on the bushings and washers for fitment, now it rides like a magic carpet.

Next up, sorting the mid drive.
I decided on number 35 chain, cuz it's dirt cheap, highly available, and you can get very high and low tooth count sprockets.

This one is a 10-tooth countershaft to an 85 tooth drive split sprocket, so 8.5 to 1 ratio, at 48 volts, and a 20-in wheel, should get me about 20 mph.

I'll get some more detailed photos posted of the build process, but from now I'm just going to put the pics I have up.

 

[neptronix]

Hell yeah!

My advice, from experience:
- put on as wide of handlebars as you can get for a way more confident steering at low and high speed
- you should be tire-maxxing. leave no millimeter unused, it will improve nvh significantly. And NVH is a problem around 30mph on this bike.

Look forward to seeing what you come up with!

 

[A-DamW]

Couple of weeks ago, my nephew was visiting from out of town and expressed interest in building an e-bike, so I said, "Let's finish this recumbent I am almost done with, and you can ride it around the neighborhood"

So we did. (He had a blast, so did I!)

I was pleasantly surprised the chain drive did not exhibit any teething problems, I thought for sure with the noise it was making, that something was going to rear it's ugly head.

The chain drive is much quieter/smoother now that it has had a few miles to wear in.

Photo dump:

 

[neptronix]

Badass!

 

[PaPaSteve]

Some clever solutions going on, especially the 85T sprocket adapter

 

[Papa]

I thought for sure with the noise it was making, that something was going to rear it's ugly head.

Drive sprockets much smaller than 13T scream like a bull Elk in rut. Might wanna keep yur eyes peeled for horny cows!

 

[A-DamW]

Some clever solutions going on, especially the 85T sprocket adapter

Thanks, you probably recognize most of the parts on that hub, but I'll describe them for anyone wondering.

The split hub clamp is one you find commonly on 49cc gas bike conversions, this particular one has a considerably broader shoulder to clamp around the hub than the typical adapter you find, it also has a nice large flange to get sprocket bolts over the hub flange.

If you look closely, you will see Mike's trademark logo from LightningRods, laser cut into the sprocket adapter, I purchased this from Mike at lightning rods last year, quite economically too.
This adapter was originally meant to bolt onto an ISO six hole disc brake hub, but I've been having a heck of a time finding a 20-in wheel with a disc brake hub.
It just so happens that the bore fits perfectly concentrically on the tapered left hand end of the wheel hub.

The 85 tooth sprocket is a standard #35 chain, go-kart/mini bike split sprocket, with mounting holes on 5 ¼ inch bolt circle diameter.
I drilled and added 2 bolts on both sides of the split to prevent misalignment and chain derailment.

 

[A-DamW]

Drive sprockets much smaller than 13T scream like a bull Elk in rut. Might wanna keep yur eyes peeled for horny cows!

Yeah, I was fairly well aware of the compromise to choose a smaller than 13 to 16 tooth countershaft sprocket. I believe they call this "chordal action".

Maybe I can write a lisp script for my vesc controller, that when I hit a button it modulates the motor to either sound like a bull bugle, or a cow call, I guess when September-October rolls around I'm going to have to pack my bow on my bike rides, in case I call one in. (I have elk in my yard year round, no joke)

 

[neptronix]

You could just run square wave to drown it out like we used to do back in the day