Reverse gearbox or hub

[Hampus B]

Hi,

I am trying to find a hub with a reverse gear. So I still pedal forward but the cargo bike moves backwards. Does it exist?
I would like to have a geared mid motor and still the possibility to go in reverse.

 

[fill]

Not as far as im aware. You can simply engage a reverse with a direct drive motor switching the phase sequence, so electronically.

to trigger via forward pedalling would require complex and expensive to design and make drive disengagement tech that does not currently exist afaik. (Edit.. ok so bike clutches exist, but not quite in the desired format.. )

edit #2-- why?

 

[Hampus B]

Not as far as im aware. You can simply engage a reverse with a direct drive motor switching the phase sequence, so electronically.

to trigger via forward pedalling would require complex and expensive to design and make drive disengagement tech that does not currently exist afaik. (Edit.. ok so bike clutches exist, but not quite in the desired format.. )

edit #2-- why?

Thanks,
It is a Cargo bike. Small moped. Maximum legal power is 1000W. So I think a geared mid motor is the best alternative. But it would be very convenient to have a reverse gear.

 

[Chalo]

Thanks,
It is a Cargo bike. Small moped. Maximum legal power is 1000W. So I think a geared mid motor is the best alternative. But it would be very convenient to have a reverse gear.

Some controllers have a wire pair that reverses motor rotation. You could attach a momentary switch to that wire pair to reverse whatever motor you have, as long as it doesn't use a freewheeling clutch. So no geared hub motors and no freewheels in the chain drive if you use an external chain reduction.

 

[fill]

@Chalo While pedalling forward?
@Hampus B , could your brain handle pedalling forward and moving backwards?

Having ridden a few heavier 2 wheeled machines without reverse capacity -no goldwings.. even if laid heavy with cargo (sacks of coal in my case 4x stacked on the pillion seat) back waddling is an easy knack to pick up and multi point turns are do-able in an emergency..

Perhaps not a Need feature?

 

[Chalo]

@Chalo While pedalling forward?

A reverse switch only reverses motor rotation. It doesn't change the method you use to engage the motor.

 

[fill]

OP wants a mid (chainring?) drive bike that will go backwards while pedalling forward?

 

[Chalo]

OP wants a mid (chainring?) drive bike that will go backwards while pedalling forward?

That's not happening, for the same reason you can't pedal a normal multi speed bike backwards. The kind of mid drive that would work is a mid mounted hub or shafted motor with a direct, no freewheel chain to the driven wheel.

 

[fill]

Location and mentioning keeping motor rated power within regs suggest a pedal drive is also required so just using pedals as sensed inputs would be out.

An interesting problem, makes me think its a 1st yr engineering xtra credit problem given the time of year.. and if so no doubt some ancient bi stable gearing solution 1st applied to a loom or tractor will fit the bill, but as only an armchair wannabe myself im stumped..

 

[lnanek]

I've seen acoustic bikes where if you pedal forward the bike moves forward in one gear, then if you pedal backward, the bike moves forward in a different gear for hills. You do have to give up the ability to pedal backward and do nothing, though.

Setup was quite easy and only needed an extra idler pulley. The chain goes back around the first rear cog like normal, then loops around the idler, then comes around the second rear cog in the reverse direction. So there are tricks like that to reverse the connection between pedal direction and bike direction.

That said, if they are asking for a reverse gear, they likely want a powered reverse gear and care little about the manual power. So leaving reverse pedaling to do nothing, just detecting it with one of the PAS magnet configurations that can detect direction, and using it to power a different controller wired up to swapped phase cables on a rear hub to go the other way would probably be easiest. Or just wire up a second throttle to the second controller, or have a set of switches to swap the phase cables from a single controller.

 

[Chalo]

I've seen acoustic bikes where if you pedal forward the bike moves forward in one gear, then if you pedal backward, the bike moves forward in a different gear for hills. You do have to give up the ability to pedal backward and do nothing, though.

Retro-direct - Wikipedia

en.m.wikipedia.org

 

[offGridDownUnder]

Some controllers have a wire pair that reverses motor rotation

A warning.

If moving your machine backwards - say by pushing with your feet from a standstill - moves the pedals backwards as well, then setting the motor to reverse will do the same.

I'm planning to install a switch to reverse the motor on my trike as it's large and will sometimes be heavily laden, but I'm also aware that I'd better not have my feet on the pedals when I do this. If I'm not careful with my settings and actions, that motor can break my ankles or gouge my shins.

I am using Grin's equipment, which includes speed limiting for reverse/walking/throttle-only modes. I still expect to take my feet off the pedals. I can do this on my trike. Unless I'm very 'side-hill', I won't fall over.

Can you back a two-wheel cargo bike when your feet aren't on the pedals? Are you certain of your stance? If you lose your balance and the bike keeps going, what happens? How about if you fall while the motor is running? How heavy is your laden cargo bike?

 

[Elias lector]

How about a separate front hub motor?