I tried the new N360 CVP hub from Fallbrook Technologies on a mountain bike at Sea Otter and was impressed with the performance and usability of the N360 continuously variable transmission.
Fallbrook made a splash in 2007 with the introduction of their NuVinci continuously variable transmission hub, but because of the hub’s heavy weight and clunky appearance, adoption has been mostly limited to gearheads and tinkerers. With the N360, Nuvinci took three pounds off of the hub’s weight, increased the gear ratio range to 360%, made the hub smaller, and reduced the ‘throw’ or twist required to move from high to low gear. Best of all, there are never any missed shifts – that alone can be worth the 2 lb weight premium over other gear hubs for some mountain bikers.
I took an N360 equipped mountain bike around for a quick spin on the demo trails are Sea Otter last weekend. I’ve tried the previous N170, and the major problems with that design — wrist wrenching 180 degrees of twist to shift and uneven feedback while shifting — are completely gone. The lack of an clicking and clacking after over 20 years of indexed shifting is a little disquieting! Shifting under load while pedaling up a steep hill is smooth and easy.
My main problem with the N360 is psychological: It’s almost too easy to shift! Think of a non-functional lever or knob on a child’s toy, and that’s what shifting the NuVinci feels like. Fallbrook may want to think about adding some kind of tactile feedback or resistance so you realize you’re actually doing something when you twist the shifter.
The N360’s major drawback is still weight. At 5.4 lbs it’s a significant improvement over the N170, but that’s still heavier than competing internal gear hubs from Shimano, SRAM and Rohloff. While the N360 is significantly less expensive than anything from Rohloff, there is a price premium over Shimano Alfine and even SRAM’s i-Motion 9.
Still, this hub is smooth and easy to use. For mountain biking, there’s no derailleur to bang against a rock. This hub is supposedly also usable in light electric vehicles and small tractors, so I suspect the N360 can handle whatever torque a cyclist can generate. The shifting is easy as pie for a novice, and you can tell exactly where you’re at with a quick glance at the shifter inchworm display. The technology works, and Fallbrook tells us it’s more than durable enough for daily mountain bike trail use.
During Sea Otter, I saw a couple of bike company designers talking seriously with Fallbrook engineers about incorporating NuVinci’s hub into their bikes, so maybe we’ll start seeing bikes built with CVT hubs in the next couple of years.
Range is too small and weight is too great for anything other than city riding (ie gentle slopes), and price is too high for city riding, so don’t think there is a market unless it can be reengineered to double the range, cut the weight or drop the price.
5.4 lbs might be too much for racers but for others it’s nothing to worry about.
After all, as a vehicle you have to take into account the weight of the rider as well as the bike, 200 lbs+.
On range, the hub alone gives gearing from some 26″ to 90″ gear-inches
(mountain bike size wheels) and there is nothing to stop you using a double chainwheel up front to increase that range if reqd.
I’ll be getting one soon
New transmission CVT design by BitRaptor. Is a continuously variable transmission CVT gear only (the only one functional in the world), very compact and lightweight, and which could replace the current systems both for efficiency, simplicity and not least the costs.
Because this CVT work only with pinions is better the all other systems by efficiency and high torque transmission.
In the web page you will find more explanations, drawings and a short video of a basic prototype.
The first prototype will be ready for tests during this year.
Other possible applications CVT design by BitRaptor are: bicycles, motorcycles, cars, automobils, boats, gearboxes, electric motors, steam and wind turbine, as well as a large number of industrial or agriculture applications whenever is necessary some adjustment of the gear ratio.
Interesting. I’ll watch for news of your prototypes.