46cc's is too much!

[dchevygod]

So... With all my component failures I've found the stock style 8 speed derailleur system to be inadequate on my application. I now have several other obstacles to overcome getting an IGH installed.

1) I need a 30+t bmx sized sprocket
2)#41 or #415 chain
3) mod a 36+ tooth crank sprocket onto a much smaller 22t drive sprocket for the internally geared hub
4) I need a chain tensioner with a beefier straighter chainline.
5) wheel lacing/truing with the new IGH.
6) new F/W's, spacers/bolts and cranks.

Basically a full overhaul on the secondary drive portion of the build. With a new final drive.

Massive changes...

 

[FurryOnTheInside]

Sounds like fun.

Just wondering what is the reason that the standard/available rear sprocket size for this IGH hub is limited to 22t? Do you have the hub?
Really I suppose I'm asking does the hub use a freewheel thread and will a SBP freewheel fit it?

 

[dchevygod]

No I'm using the calculations/ butt feel from this setup that works till the chain stretches or something else goes out of whack. I think freewheel.

 

[dchevygod]

I want a sturmey archer s80. 1st is 1:1 with all the other gears overdrive that's what I need! No... THE driver takes a special cog so i need to modify.

 

[dchevygod]

23t is the largest cog I've found. I need a 34t cog on THE 1:1 1st gear. I've found lots of discrepancies...

 

[FurryOnTheInside]

I want a sturmey archer s80. 1st is 1:1 with all the other gears overdrive that's what I need! No... THE driver takes a special cog so i need to modify.

The one with the three little prongs and it's dished too. Eek! I guess you'll be welding to it then.

 

[dchevygod]

Found a 24t! Still not the ratio I need.

 

[gary55]

23t is the largest cog I've found. I need a 34t cog on THE 1:1 1st gear. I've found lots of discrepancies...

Why not go Nuvinci 360 hub? Way better than strumey and with .5 under to 1.8 0ver it's great on the hills, takes of from a dead stop, and cruises at 35mph with a 22 rear cog like the engine is hardly working.

 

[dchevygod]

Great suggestion Gary, but the nuvinci hubs from what I've seen are out of my price range.

Also I run a high revving gp460 4.2hp rated @ 11k rpm. I want take off gear to be 1:1 to avoid grenading a $200 hub. Underdrive would be nice if it could handle the torque im punishing it with! I've read on the E bike forums that IGH's are weakest in underdrive on take off. Though all the torque is instant on a mid-drive electrics. So maybe that's a non issue. But these motors are pretty mean!

 

[dchevygod]

I'm used to Zenoah/chung yang Goped/RC engines that when ported/piped spin 15K+ RPM! I estimate my 460 with a pipe and mild exhaust porting at closer to 6hp and it revs to 14K easily.