Silly build idea:

[cloakedvillain]

Hyper cruiser frame, bt80 electric start, jackshaft the output to the right side of the bike (as in right and left not right and wrong) into an automatic 2 speed hub. No clutch lever, no shifter cable, just the brakes and throttle for a clean looking build.

 

[Sidewinder Jerry]

Is the Sram 2 speed auto hub what you're referring too or are you talking about a Strumey Archer kick shift hub? If it's the Sram are you planning on making it a jackshaft transmission so that you won't need a shift kit? Then you could simply put a centrifugal clutch on the engines drive shaft. Ok took a look at the engine and it comes with a built in centrifugal clutch.

If you did the jackshaft transmission, you could put a 52t sprocket on the left side of the rear wheel. Once you got up to speed for a gear change it be like having a 38t sprocket on your bike.

The SRAM Automatix 2-speed Bicycle Hub

An article giving information on use, adjustment and rebuilding of the SRAM Automatix hub.

www.sheldonbrown.com

SRAM Automatix two speed hub review • Dave McCraw

Solid two speed coaster brake hub with funky automatic shift- the SRAM Automatix is reviewed including changing the shift point...

web.archive.org

 

[cloakedvillain]

Is the Sram 2 speed auto hub what you're referring too or are you talking about a Strumey Archer kick shift hub? If it's the Sram are you planning on making it a jackshaft transmission so that you won't need a shift kit? Then you could simply put a centrifugal clutch on the engines drive shaft. Ok took a look at the engine and it comes with a built in centrifugal clutch.

If you did the jackshaft transmission, you could put a 52t sprocket on the left side of the rear wheel. Once you got up to speed for a gear change it be like having a 38t sprocket on your bike.

The SRAM Automatix 2-speed Bicycle Hub

An article giving information on use, adjustment and rebuilding of the SRAM Automatix hub.

www.sheldonbrown.com

SRAM Automatix two speed hub review • Dave McCraw

Solid two speed coaster brake hub with funky automatic shift- the SRAM Automatix is reviewed including changing the shift point...

web.archive.org

The automatic 2 speed and sturmey archer made one too. The idea is to go straight into the hub with the jackshaft with no pedals at all on the bike. Now its just an idea, if I had the money and time my dad would love a build like this but I'm not sure I would ride it because I just don't like the beach cruiser builds.

 

[Sidewinder Jerry]

The automatic 2 speed and sturmey archer made one too. The idea is to go straight into the hub with the jackshaft with no pedals at all on the bike. Now its just an idea, if I had the money and time my dad would love a build like this but I'm not sure I would ride it because I just don't like the beach cruiser builds.

Unless you plan on installing a monster of a clutch a pedal assist on take offs will greatly increase the life of the clutch.

 

[Sidewinder Jerry]

Is this the SA hub you're referring to then?

Sturmey Archer A2D Internally Geared Hub - 2-Speed 36H 70mm Drum Brake Silver

Sturmey Archer A2D Internally Geared Hub - 2-Speed 36H 70mm Drum Brake Silver. A2 Series internally geared hubs feature an automatic 2-speed shift system with a gear ratio of 137%.Aluminum hub shell TECH SPECS Bearing Type Loose Ball Cassette Body Type 3 Prong Cog Color Silver Defined Color...

thebikehub.com

 

[cloakedvillain]

Unless you plan on installing a monster of a clutch a pedal assist on take offs will greatly increase the life of the clutch.

Like I said, just an idea. Good advice though.

 

[Sidewinder Jerry]

Like I said, just an idea. Good advice though.

The thing with the jackshaft to drive the right side of the IGH is it can give you 2 more reduction points. This way you could run a smaller sprocket in the rear but it'd still give you the same reduction as if you'd ran it straight to a 54t sprocket.

I suggest running Engine 10t > [JS 19t/ JS 10t] > [Hub 19t/ Hub 24t] > rear sprocket 36t.

Then you can do a rear wheel setup like Damien with a large rear disc rotor on a 3 spoke mag wheels. The setup would be like having a 54t rear sprocket and a 40t rear sprocket. This would give you a cruising speed around 28 mph and a max speed around 38 mph using 26" wheels.

My big fear is without a pedal assist on take-offs you'll probably blow the IGH out.

 

[GW's Motorized]

Why not just go with a regular 3 or 5 speed igh. It would be like shifting an old honda. Just let off the gas, pop it in the next gear, and roll back on the throttle.

 

[Sidewinder Jerry]

Why not just go with a regular 3 or 5 speed igh. It would be like shifting an old honda. Just let off the gas, pop it in the next gear, and roll back on the throttle.

Most places which do allow self-built motorized bicycles/mopeds have an automatic transmission clause; meaning no manual shifting of engine driven gears. Several places requires one to pass a DMV inspection to be able to ride legally on the public roadways. If you're a large person and/or live where there's steep hills, you need mutiple drive ratios when using a small engine. Builds that can shift engine driven ratios automatically offers a legal loophole.

 

[Whitewill1412]

What is this "legal" thing you speak of?