Constantly Variable Planetary Gear

[betty swollocks]

here

 

[TheDoctor]

I'm sure VeloVision had a write-up about these a while back...
It's bloody heavy!

 

[Bigtwin]

Link dead for me.

Is this about Neil Armstrong's vast space suit wardrobe?

 

[TheDoctor]

Workes for me a few mins ago...
It's a continuously-variable hub gear. Sounds to me like a solution in search of a problem, but most things are when they're first invented, I suppose.

 

[Bigtwin]

Aaah - workey now.

I seem to recall these being used on motorcycles a while back, though I can't recall which one. Used on cars etc already of course (CVT in various forms).

Can see the advantage for town bikes where the weight's not an issue so much, and that does seem to be a reasonable price for a change. Or rather for not a change.

 

[threebikesmcginty]

I'm sure VeloVision had a write-up about these a while back...
It's bloody heavy!

Yes, I seem to recall an ad in Velovision for this.

 

[Davidc]

Buried in the article is this

"the NuVinci CVP will be less mechanically efficient than direct drive transmissions"

The range is also low. To get a 550% range you'd still need 2 ring front mech.

Good idea, needs more work!

 

[Joe24]

Doesnt sound gaan fe bed a bad idea, but is it too complex dough?

 

[mickle]

Doesnt sound gaan fe bed a bad idea, but is it too complex dough?

Even by your standards that was a piss poor post.

 

[Joe24]

Even by your standards that was a piss poor post.

mickle de i-man let i-man down sometimes, kyan the i no just be cheery for once?

 

[mickle]

mickle de i-man let i-man down sometimes, kyan the i no just be cheery for once?

The NuVinci hub though a little heavy, less efficient, of limited range and expensive is an excellent product don't you think? Starting with bicycles their plan is to prove that it works on increasingly larger applications/ vehicles, developing it as they go. I'd love to see it paired with an 'auto' shifter too.

 

[Joe24]

The NuVinci hub though a little heavy, less efficient, of limited range and expensive is an excellent product don't you think? Starting with bicycles their plan is to prove that it works on increasingly larger applications/ vehicles, developing it as they go. I'd love to see it paired with an 'auto' shifter too.

Yes, excellent.
Although, i do sort of like the concept, you dont get a big jump between gears, can just have a smaller one.
But, surely if you want to change to a lower gear/higher gear fast, it wont be so good because you will twist either too far/too little.

 

[mickle]

Infinitely variable means no jumps between gears just a smooth transition from one end of the range to the other. Not steps, a ramp if you will.

I wonder if a fixed wheel version is possible.

 

[Joe24]

Infinitely variable means no jumps between gears just a smooth transition from one end of the range to the other. Not steps, a ramp if you will.

I wonder if a fixed wheel version is possible.

That would be interesting.
But am i right in thinking that you can just adjust the gear your in slightly?
Surely this will mean that when you want to go through a few gears or whatever, its not so easy. Or am i thinking wrong?
It will work like a friction shifter, but not have the steps.
Maybe i am thinking about it wrong

 

[mickle]

Think Gripshift shifter with no clicks. Like a motorbike throttle.