Printable gear box?? and sprocket adapters.

[Hugh-Jassman]

I am still searching for appropriate sized narrow profile, low rpm motor that does not need a large gear reduction to the drive wheel, a one stage reduction will probably not be possible. And I know that not many people like the idea of a slow single speed e-bike. But for a heavy duty cargo bike it is the best way to go.

I think it will be absolutely necessary to build some kind of two speed gear box. So I have been thinking about this one that looks like maybe it could be printed in various parts.
Is it possible to print with hard enough materials like maybe epoxy of some sort?
Maybe print the original parts then mold them out of harder materials?

https://www.youtube.com/watch?v=kmJADKX5yaw&t=79s

[youtube]kmJADKX5yaw&t=79s[/youtube]

Some one should design a printable gear box with only two or three ratios, and put it out there on the internet for free, in-order to subvert the corporate ownership of information.

450lbs with 8 to 10% grades dictates at least a 750 watt nominal motor. And more than likely it will need to be called a 1000 watt just to get up around 1500 watts for the worst of the hills. Maybe I should just make a plaque with the right numbers on it to use a more powerful motor.

And I am stalled out at not finding a sprocket adapter that will fit onto the free-hub body behind a modified cassette, maybe 6 or 7 speeds.



for printable belt pulley: https://endless-sphere.com/forums/viewtopic.php?f=1&t=92388#p1351182

 

[spinningmagnets]

One year a while back, there was quite a lot of 2-speed transmission discussion. Miles consistently promoted the retro-direct method (reversing a non hub motor) and after a great deal of study, I agree with him.

https://endless-sphere.com/forums/viewtopic.php?f=28&t=7679&start=0

 

[Hugh-Jassman]

Searching for sprocket adapters I saw this page “OneUp 45 Tooth XTR Conversion” but what I really need is a way to use a motorcycle sprocket for a #35 chain, maybe 65 sprocket teeth? But will bicycle sprocket pitch work for a #35 chain?

http://www.pinkbike.com/news/oneup-45-tooth-xtr-conversion-review-2015.html

Well now I am thinking that I can just take and old cassette and remove the 34t sprocket, drill holes then bolt on the motorcycle sprocket. I have searched for this concept on endless sphere, but with out the right words, nothing shows up.

Yet it looks like I could use one of these “OneUp” sprocket adapters for the motorcycle sprocket. Or do I need two of the bicycle sprockets from a cassette to hold the motorcycle sprocket?

And finally I will put a smaller cassette on the free hub, like maybe a 6 or 7 speed.

It looks like for a #35 chain the sprocket will need for more teeth maybe a 120? or more....does anyone know how many teeth wouold fit into a 6 to 8 inch disc? maybe I can calculate it.
and where can I get such a large sprocket for teh #35 chain?

http://www.pinkbike.com/u/mikelevy/album/OneUp-45t-XTR-Conversion/

or maybe I need the right kind of cassette:

a 72 tooth sprocket:

#35 72T Go Kart Sprocket 4 Bolt

http://www.quickieparts.com/go-kart...-4-bolt.html?gclid=CNPdqpC5i9ECFeHhcgode2gJcA

 

[Tony01]

That yt link above looks like a ravigneaux gear set. Good luck finding one small enough for us. I'm working on a 2-speed for gas bikes. I already have the gearset, it's a .625 first gear with direct 2nd and the gearset overall is 4.5"X1.1". Will be using it with my 10hp 212cc motorized bike (that tops out around 60mph). My design would be a lot simpler with only one clutch for the shift for an ebike.

I don't think you'll have much luck with printing gears. Not enough precision and strength in the 3D print process.