CVT Nuvinci/ worthless for hill climbing

Well, I have one, but haven't finished the bike it is on yet. It is a bit heavy, but I am also eliminating the weight of the derailleur and associated mechanics. I may be getting ahead of myself, but I am pretty confident from reading reports, and going over the specs that it will do fine for me. IMO of course. Mine will be driven by a dual freewheel on the right side for the input....one for pedal, and one for engine, with virtually no drag gong from one to the other. hopefully. :D
 
Motor torque?

So far no one is saying any thing about what a motor will do to it.

Will a one HP or even a 750 watt motor over torque it? well maybe if set up correctly it can accelerate slowly? but at what gearing?

And will I ever be able to climb the any hills with 450lbs?????

I presume that over torque will make it SQUEAL?
 
The hub's intended application is for a bicycle, not likely a quarter ton bike. And not likely a quarter ton hill -climb bike.
You are out in the wild frontier where no man has gone.
Also, any motor that is in it, will likely over heat unless it geared real low to relieve the load placed on it or it water cooled and designed for such a load -regardless of the type of motor and drivetrain.

Everything has limits.

I peronally don't like to test limits unless I am protected from possible catastrophic results. It's also not enough to feel lucky.
Sorry that we cannot answer your questions.
 
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jawnn - do you have this hub installed? Because the title of your thread implies that you do, and it has been proven to be useless for hill climbing.

The info I saw, said that the hub was rated up to about 6 HP

1 HP is 746 watts... (750 when rounded to the nearest 10 watts)

The formula for calculating torque when you know the HP is

T = (HP x 5252) / RPM

If we assume that you've geared the motor down to about 120 RPM, then, for a 1 HP /750 watt motor, the torque is 43.8 ft-pounds.
 
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Also, note that few roads in this country have greater than 10% grade. (a 10% grade is a pretty steep road...) For a 10% slope, you would need, for a 450 pound load (inc. bike, motor and rider,) apx. 45 pounds 'thrust' to maintain speed.

With a 24 inch wheel (chosen because the radius of a 24 inch wheel is 1 foot...) then the 1HP motor geared down to 120 RPM would almost take you up the hill unaided. At 117 RPM, it would do so.

117 RPM on a 24 inch wheel is 8.35 MPH

If you're using a smaller wheel, the same RPM would, of course, produce a speed that is less, by the ratio of wheel diameters, and the slope attainable would be correspondingly greater (again, by the same ratio).
 
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The hills here are too steep.....

I was in the practice of clibing a 16% grade with 400 lbs with just my legs using oly 10.5 grar inches, not quit low enough. My psoas muscle is killing me now so I must stop and pay for power.

the hill is short but messures a 3.4" ? rise over 20"... it's been a while sence I messured it. maybe it changed.....not.

well I found this http://www.motoredbikes.com/showthread.php?t=8227 thread good info.


STILL WISHING FOR PHOTOS
 
So far no one is saying any thing about what a motor will do to it.

Will a one HP or even a 750 watt motor over torque it? well maybe if set up correctly it can accelerate slowly? but at what gearing?

And will I ever be able to climb the any hills with 450lbs?????

I presume that over torque will make it SQUEAL?

I thought I did.

You need to contact Clotho. He is not a small guy, he lives in an area with hills and has had a shift kit and Nuvinci for almost two years.

You use the word "worthless". No way.
 
"120 lbs pull (55kg).will lug over 400 lbs up a 25% grade!"

This is a de-rated calculation; the maximum 'thrust' output calc for the Nuvinci was 170 pounds...
 
what I realy need

There is a lot of effort to say that the thing will not slip if set up correctly.
If a one hp motor is several times stronger than I am I would have to put a 76 sprocket chain ring on the motor and 18 on the hub, that may reduce the torque but increase the speed witch will not be reduced any where enough to actual drive a heavy load up a steep hill.

I use 10 gear inches 18 sprockets on the crank and 34 on the hub with a 20" wheel to climb a 16-17% grade [(4"/100) / (24"/100)= .16666] at 1.5 mph with my legs only.

Obviously I really need a motorcycle transmission and connect the to the drive wheel with an automotive timing belt. Last year I tore two chain link plates, not at once, but I am using the bicycle stuff at its limit. A motor would destroy it much faster.
 
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