Motorized recumbent tadpole W/CVT pics

GoldenMotor.com

Tohri

New Member
Aug 28, 2010
159
0
0
People's Republik of Massachusetts
Hey everybody. First post here, but I've been trawling the site for clues on my first scratch build.
Just to set the stage: I'm from Mass, and got my A.S. tech degree in Mechanical engineering with this as my final design project. It's an incomplete prototype, and I want some input on where to go from here, but I think I have the basics covered.

Oh, also Wood.







I think all of you know exactly what's going on here, but feel free to ask some questions.
And yes, The frame is plywood.
Yes, the steering gear is plywood.
No, the fuel tank isn't plywood, it's just shrouded.
Yes, the steering is ackerman compensated.
Yes, I did use a trigger shifter for the throttle.
And no, it only weighs about 65 lbs.
 

skyl4rk

Member
Aug 14, 2008
156
3
18
M I C H I G A N
Is the hammock style seat comfortable?

What type of hubs do you have on the front wheel? Are they special to allow mounting from one side? Is the axle beefed up at all?
 

4950cycle

New Member
Sep 8, 2010
111
1
0
Dunnellon,FL.
Thank you for the source on the CVT. I wonder if I could adapt it to a 66cc chinese ? Ithe If it worked well on that, I would try to figure out how to get one on my Puch Maxi moped. The thing has only one ratio just like 99% of motored bikes. And BTW , have you noticed how much variance in the ratios that little CVT has ? ie. Is the gain worth the labor ? Thank you for the link and the advice
 

curtisfox

Well-Known Member
Dec 29, 2008
6,046
3,948
113
minesota
Go to ( DIY home built section and find CVT rack mount by neattimes.) The ones I bought have a 5-1 buit in gear box plus the cvt is 7-1 I think but notsure on that part.but close. I have another sourse I will look later...........Curt
 

Tohri

New Member
Aug 28, 2010
159
0
0
People's Republik of Massachusetts
The CVT is worth it for the gain in the low end, but use anything besides the little CAG motors, they're not at all robust enough for this sort of build.
The biggest problem with the CVT units is the way the chain has to be run, since it outputs to the right hand side of the bike instead of the left. So either run singlespeed like Neat Times, or make up a jackshaft.
As for mounting on a happy time motor: Snowball in satan's locker room, the operating principles are incompatable. A variator gearbox could be designed and fabricated in theory, but it'd be expensive to build, and possibly unweildy. A nuvinci style hub is more ideal. Or the SBP shifter kit.
And to skylark: The hammock seat is very comfortable for long distance rides just because you can shift your position around on it if you start cramping up. A little unstable in high gee turns, but I'm working on that.
As for the rims, they're basic 14mm axle bmx 20" rims, with the axle backed out one side to allow more mounting room. Sooner or later I'll pick up some grade 8 bolts off Mcmaster and do it the right way.


Overall, I went with this form factor because I wanted a motorbike with CVT, and this was the only logical way to build one. You could probably build a recumbent bike with a CVT motor too, especially if you were handy with a TIG welder.
 

curtisfox

Well-Known Member
Dec 29, 2008
6,046
3,948
113
minesota
Hum I am going to have to double check that. I planed on using a Honda 50 witch requires about a 2 inch spacer to mount the clutch.I thought it could fit so the chain would run on the left. Maybe the pedales would hit. I better mock up and check befroe I go do any more........Thanks ...Curt
 

Chippa

New Member
Nov 5, 2015
8
0
1
Round Rock, Texas
Hey everybody. First post here, but I've been trawling the site for clues on my first scratch build.
Just to set the stage: I'm from Mass, and got my A.S. tech degree in Mechanical engineering with this as my final design project. It's an incomplete prototype, and I want some input on where to go from here, but I think I have the basics covered.

Oh, also Wood.







I think all of you know exactly what's going on here, but feel free to ask some questions.
And yes, The frame is plywood.
Yes, the steering gear is plywood.
No, the fuel tank isn't plywood, it's just shrouded.
Yes, the steering is ackerman compensated.
Yes, I did use a trigger shifter for the throttle.
And no, it only weighs about 65 lbs.
 

Chippa

New Member
Nov 5, 2015
8
0
1
Round Rock, Texas
I realize this Tohri guy is probably not posting anymore, So I was wondering if anyone else out there can answer a question.

It looks like his "Kingpin" is forward of the front weel center line (i.e. axle). Has anyone tried this and if so how does it handle as related to steering on straight lines and in corners?