this is kinda an odd question

[snowranger]

Hear what you are saying, but now you can't take advantage of gear ratio changes with a left hand side drive. Wouldn't a Nuvinci in the rear suffice?

 

[potatonet]

yeah. this is what I was getting at, If I drive the rear ONLY then I dont get the gearing. I could theoretically just hook up a nuvinci CVT on the rear...

do you have a picture of this freewheel that you have setup? basically that would be the way I would set it up, I guess I am asking a LOT of the chain to pull 1000 lbs up 10% grade.

hmm... pics pics pics???

can you run the nuvinci with a double drive?

thats what we need here. a hub transmission that allows for either side to input! brilliant!

 

[snowranger]

I guess you could use a scooter or motorcycle chain. The part that escapes me is how the crank freewheel works. Would this kit do the trick?

http://sickbikeparts.com/catalog/product_info.php?cPath=21&products_id=86

 

[recumpence]

Its not just the cain, but the sprockets as well.

Also, the Nuvinci would probably break under this much stress.

Matt

 

[snowranger]

Here are the specs for Nuvinci:

Torque, Power, and Speed Limits*

Maximum Sustained (Pulse-free) Input Torque 65 Nm (48 lb-ft)
Maximum Instantaneous (Spike) Input Torque 130 Nm (96 lb-ft)
Maximum Sustained Input Power 5 kW (7 hp)
Maximum Recommended CVP Speed Input: 1000 RPM / Output: 1000 RPM
*Operation at these limits is not recommended for extended durations, and durability is highly dependent on duty cycle. Higher RPM, torque and power configurations can be designed for production applications.

 

[potatonet]

I will be putting in more than 48 lb ft continuous... a lot more

I guess I will just put a gear with a freewheel on the disc break mount of the axle.

36:1 will have to do and Im SURE it will give me enough speed and the torque to pull 1000 lbs

 

[snowranger]

Yep, it is kind of wimpy. The 5 kW figure caught my mind. The rest not so impressive.

 

[potatonet]

Would it be better to belt drive this system or should I stick with a chain ?

 

[recumpence]

Definately a chain. No doubt on that one.

Matt

 

[potatonet]

so could I theoretically just upgrade the chain on the bike to handle more power?

Is it just that putting that much power on the crank will mess up crankset bearings/ gears?

 

[JS Tyro]

Yep, it is kind of wimpy. The 5 kW figure caught my mind. The rest not so impressive.

Since when are bicycle parts supposed to handle motor loads? You should be more realistic in your expectations.

 

[recumpence]

so could I theoretically just upgrade the chain on the bike to handle more power?

Is it just that putting that much power on the crank will mess up crankset bearings/ gears?

The rear sprockets are a problem too. With alot of power and a low ration, you have huge torque at the chain. If you run a left side drive, you can use a large (50 tooth?) rear sprocket. That will drastically reduce the torque on the chain and sprockets. If you are running through the stock drive train, you will be running a low chain surface speed, thus increasing torque loading substancially.

Plus, a heavy duty BMX chain is best and cannot be run through a derailer.

Matt