Forum name

[neptronix]

That's a temporary change to make posts easier to move. But i do kinda like how it puts our core topic first.

 

[fatty]

Natural language? For ?Grantmac, the chains need not be parallel for two drives, but the planes of their motion likely are parallel. Two drive chains can be at right angles on the same bike axle, which is not parallel chains, but their planes of motion need to be somewhat parallel.

Well, if nothing else, this illustrates the opportunity for confusion when using parallel/serial descriptors -- common in hybrid EV discussion, but not in ebikes or pure EVs, obviously..

 

[Hummina Shadeeba]

I’m skipping through trying to find threads about mid drive motors and using the bottom bracket and cranks as a jackshaft and to be able to pedal if needed. So motor drives a chain to one side of the cranks and then another chainring on the other side of the cranks and that chain going to the driven wheel.

Is that available?

 

[thepronghorn]

I’m skipping through trying to find threads about mid drive motors and using the bottom bracket and cranks as a jackshaft and to be able to pedal if needed. So motor drives a chain to one side of the cranks and then another chainring on the other side of the cranks and that chain going to the driven wheel.

Is that available?

Why do you want the chainrings on opposite sides of the bottom bracket? Normally they are on the same side of the bottom bracket. Example pic below of a tangent drive.

 

[Hummina Shadeeba]

I’m skipping through trying to find threads about mid drive motors and using the bottom bracket and cranks as a jackshaft and to be able to pedal if needed. So motor drives a chain to one side of the cranks and then another chainring on the other side of the cranks and that chain going to the driven wheel.

Is that available?

Why do you want the chainrings on opposite sides of the bottom bracket? Normally they are on the same side of the bottom bracket. Example pic below of a tangent drive.
tangentdrive.jpg

i realize that now. i hadnt seen the cranks before. But please read my last post here:https://endless-sphere.com/forums/viewtopic.php?f=51&t=112421&p=1663562#p1663562
and tell me what you think.

i see the tangent drive is product name and it has a 20:1 reduction. no wonder they dont bother using the two chainrings as a jackshaft. how efficient is the gearing? ..... .. i see a cycloidal gearing is only like 80% efficient. i think they should use the two chainrings instead as a jackshaft instead! i figured i could get maybe 1:12 using the freewheel cranks as a jackshaft and do 8000 rpm with the motor and get the highest power output that way. maybe its not really the case but it seems the advantage of the big gear reduction of the cycloidal drive is lost in its inefficiency.