Nuvinci N360 and Bosch mid drive, a good combo?

[alfantastic]

Just wondered if the Nuvinci N360 and Bosch mid drive are a good combo in an off-road bike, as shown in this link for the Grace MX bike.

http://www.grace.de/produkte/grace-mx/?L=1

 

[iperov]

nop
nuvinci efficiency < 75%
Just spend energy to heat the hub.

 

[MattyCiii]

I've been riding the N360 since it came out. Now granting that I put pedal power only through the NuVinci transmission, there's no way it's only 75% efficient. Not unless all the derailleur equipped bikes I've ridden between are also 75% efficient - which isn't the case.

But that's just my own personal experience.

Having said that, it's interesting that the market for NuVinci seems to be growing still (i.e., it can be found on an ever widening variety of bike brands and types). My intuition tells me that all those companies and customers can't be wrong. If it really lost 25% of pedal effort, the company would be out of business, not expanding their market share.

Clearly I'm biased towards this system. I'm not affiliated with the company, nor do I own their stock. What I am is a happy customer, happy enough to have purchased & installed the NuVinci on all three of my bikes (including the two linked below in my signature).
~Matt

 

[Miles]

The trouble is that we don't have any real data... A variation between 80% and 92%, depending on the ratio used seems realistic. As some of the losses are from slippage, it might well be worse than that for a high torque throughput... Just guessing....

Any volunteers for testing?

 

[iperov]

If it really lost 25% of pedal effort, the company would be out of business, not expanding their market share.

why? its good for bikes for grandmothers, not for even amateur sport.
Of course I tested N360, this is my previous bike:

I cannot reach ppl whose physical condition worse than mine during our friends riding!

 

[Miles]

Of course I tested N360, this is my previous bike:

So, how did you arrive at 75%? With what ratio and torque input?

 

[boostjuice]

The problem I find with my N360 (only used under pedal power) is that the further you are toward full underdrive ratio, the more energy is absorbed compressing all the little radial springs in the internal torque limiting clutch (much of which is turned into heat I suspect). It gives a seriously spongy pedal feedback feeling - like pedaling through sand when ascending hills, and the nonuniformity in the hub's efficiency is definately noticable - definately worst in full underdrive, while It feels like 1:1 is best, but full overdrive doesnt feel as inefficient as full underdrive. Also, when standing on the cranks applying pulsating torque in full underdrive I regularly cause the torque limiting clutch to slip which gives a sudden loss of crank tension, a disconcerting clunk, and a bashed knee against my handlebar :| . Needless to say, im over it and im ditching it for a standard deraileur setup until I can justify the coin for an Alfine 11 - unfortunately a Rohloff will always be beyond the horizon.....

 

[alfantastic]

The Bosch motor is going to provide a lot more power through the chain/belt than pedaling alone.
The S-Pedelec version of the Grace MX is capable of reaching speeds of 45kmph.
What do owners of the Nuvinci system think of the long term robustness of the unit combined with a motor?

 

[k-harvey]

I'm thrashing a NV with 12oow 36v cyclone with the drive through the right side (NV side ) goes realy well ,real quick round town,but we'l see how it lasts , If without motor I'd not have it as there is about 5-10% loss & with peddling u need it all ,

 

[alfantastic]

I'm thrashing a NV with 12oow 36v cyclone with the drive through the right side (NV side ) goes realy well ,real quick round town,but we'l see how it lasts , If without motor I'd not have it as there is about 5-10% loss & with peddling u need it all ,

Thanks k-harvey, I would appreciate it if you would bookmark this thread and maybe give another update after another 1000+ miles :wink:

 

[k-harvey]

With my Nuvinci i always feel i need the excess power of 960w for its efficienty (as there is definatly some loss)& when riding my 500w cyclone with absolute perfect derailer gear changes from a good bike I don't feel i waste a drop of power etc doing the hills & to me to be less than 500w i'd definatly not do 20km per hour up our hill less than that isnt good enough i reckon. 500w can be illegal but who's to know what wattage if its a kit & fitted by oneself. Only more time fixing chain & greasy hands--- hell I'd like that 500w in the crank though.

 

[TroySmith80]

I'm thrashing a NV with 12oow 36v cyclone with the drive through the right side (NV side ) goes realy well ,real quick round town,but we'l see how it lasts , If without motor I'd not have it as there is about 5-10% loss & with peddling u need it all ,

How is it holding up?

 

[teslanv]

I am very interested in this topic as well.

I built a Mid Drive Commuter recently, and bought a Nuvinci N171b Developer's Kit on a whim for cheap, but once I started reading up on them, I realized the efficiency might be an issue.

I started tracking my average watt-hours based on my average commute and after 200+ Miles of riding, I am getting an average efficiency of 13.5 Watts per mile. This is with an 8-speed rear derailuer and a single 48T chainring.

I have not yet invested in the additional costs of Lacing my Nuvinci hub into a wheel and installing on the bike, and actually am thinking I would just sell the Nuvinci.

I think what needs to happen for a really scientific analysis is for someone to track average watts per mile before (Like I have done) and then after installing the Nuvinci Hub. I think it will also take a bit of "playing around" with the exact rear cog size, and shift profile of the hub to dial it in to the bike for maximum efficiency.

My thought was to size my rear cog so that the 1:1 ratio of the Nuvinci would be at my ideal gear ratio and speed on the flat - for me, that is a 16T rear Cog and 16 MPH, at a cadence of around 68 RPM. (Yes, I am a lazy pedaler)- This would in theory maximize my efficiency for the CVT.

 

[d8veh]

I installed a Nuvinci N360on my bike with a GNG gen 2 crank-drive. The first time I went out on it, I rode about 20 miles without switching the motor on to see if there was any additional drag. I couldn't detect any at my average speed of about 10 mph (I don't pedal hard). I went out for a 25 mile ride with a friend who was on my 500w geared hub-motored bike, while I was on the GNG. He recorded 10.5 aH, and i recorded 11.02. We're both the same weight, and both bikes have the same battery and controller. The journey was moderately hilly, with some quite steep ones.