NuVinci

[Mike45]

you have two types of NuVinci, the one with automatic shifting is the Harmony. The other type is the Infinity. The Harmony is of course more expensive because it comes with an integrated computer.
http://www.nuvincicycling.com/en/products/overview.html
TBH, for hilly terrain, if you get a BPM bike, set your gear to whatever is your favourite, and pedal at your favourite cadence, as much or as little as you like, the motor is so flexible that it does the rest without whingeing. It's not the money, it's the simplicity (or complexity) of the way these things turn out in the field. No need for a heart monitor.

Bogarts! A hole in my research. Thanks for that snippet.

 

[Mike45]

There are two types of NuVinci gear change, both are stepless but one is automatic and one is not.

Both do the job, but the manual one requires a firm twist on the twist shift.

As a general point, I found the NuVinci sucked power.

A Bosch bike with a NuVinci I tried felt very stodgy compared to my Bosch bike with a Shimano Alfine 11 hub.

The power drain matters because no legal ebike motor is a ball of fire to start with, so I reckon you can't afford to lose any grunt.

So, the non automatic NuVinci is roughly midway between the automatic NuVinci and the Nexus 8?

 

[Croxden]

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[flecc]

So, the non automatic NuVinci is roughly midway between the automatic NuVinci and the Nexus 8?

In efficiency terms the two NuVincis will be identical, it's just the changing that's eased by the auto system. The Nexus 8 I'd consider a bt more efficient, but the difference won't be great overall. The Nexus 8 has efficiency that varies widely according to the gear that's selected, while the NuVincis will have a more constant efficiency figure with changing ratio.
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[Mike45]

In efficiency terms the two NuVincis will be identical, it's just the changing that's eased by the auto system. The Nexus 8 I'd consider a bt more efficient, but the difference won't be great overall. The Nexus 8 has efficiency that varies widely according to the gear that's selected, while the NuVincis will have a more constant efficiency figure with changing ratio.
.

I seem to have come full circle. The NuVinci is inefficient which is important when the motor is only 250w. The Nexus 8 is only marginally more efficient. Looks like I'm back to to a rear hub Bafang motor with derailleur gears!

 

[Kudoscycles]

I seem to have come full circle. The NuVinci is inefficient which is important when the motor is only 250w. The Nexus 8 is only marginally more efficient. Looks like I'm back to to a rear hub Bafang motor with derailleur gears!

Yep.....which is the conclusion that most of us have come round to...you only make a decision of Nuvinci or Nexus hub gears when you have a hatred of derailleur.
The Nexus works ok when the motor is in the front,thus the Nexus is only being asked to cope with the rider power.
The Nuvinci is a very smooth gear change and can take crank power plus rider power but you lose power efficiency.
The derailleur with chain is a particularly efficient system for transferring rider power to the wheel but it struggles to handle rider plus crank drive power which is the downside of the crank motor.
At the moment BPM hub motor plus good quality derailleur (Shimano Deore)seems the best system currently available.
KudosDave

 

[flecc]

I seem to have come full circle. The NuVinci is inefficient which is important when the motor is only 250w. The Nexus 8 is only marginally more efficient. Looks like I'm back to to a rear hub Bafang motor with derailleur gears!

That's the popular choice Mike, so you at least know it's a tried and proven one.
.

 

[anotherkiwi]

Quality and set-up are the key. And I find that the Shimano Acera is good enough quality. The Tourney that was on before was a POS always needing to be adjusted. Since I have installed the Acera I have not needed to touch settings (2200 km and counting).

A derailleur can handle the power of a BB motor WHEN IT IS IN GEAR. It is the gear changes that it doesn't like.

From the Rohloff site "The Rohloff SPEEDHUB 500/14 has been developed for racing which means that it can handle the heavy loads encountered during competition. Maximum torque loads in extreme conditions can be as high as 250Nm on the crank (= 150kg on the pedal). "

 

[flecc]

Quality and set-up are the key. And I find that the Shimano Acera is good enough quality.

Me too, Acera on my last two bikes and they almost never need adjusting. The rear mechanism copes with megarange sprockets too.
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[Spotty dog]

A bicycle becomes inefficent the moment you fit an electric motor, I view the Nu Vinchi Harmony as one more inefficency that makes riding my bike easier.
The problem with the BBS 01/02 motors are the torque just comes in bang from zero rpm.
I just didn't like the harsh bang and grind of mistimed shifting on my first derailluer set up, that thin bendy chain asked to cope with forces way beyond what it was designed for.
My first Nu Vinchi set up was a 250w BBS 01with a manual cable shift the improvment was to me worthwhile, the twist shifting does stiffen if under full load but you soon learn to shift down before you motor is pulling hard under load.
Range on the bike with a 15 ah battery was about 25 miles in the quite hilly area I ride, so im not so sure the so called power losses it creates amount to much.What did become noticable was because it is a variable ratio I found myself hunting about for the cadence I wanted to pedal at, I got lucky in finding a Harmony autoshift kit on ebay.
The NuVinchi with the Harmony shifter is so nice and easy to use, I just set the cadence and enjoy the ride while the bike shifts gear to suit the speed/road conditions.
My girlfriends bike now has the BBS 01 Nu Vinchi harmony with upgraded controller to 350w for the steep hills she has to get up, altho if it was 250w I doubt she would really notice much difference.
I run the same setup with a BBS 02 48v more power but everything works the same seemless smooth shifting works great in stop and go traffic.
An inefficent bike thats quick and easy to ride.

 

[Mike45]

A bicycle becomes inefficent the moment you fit an electric motor, I view the Nu Vinchi Harmony as one more inefficency that makes riding my bike easier.
The problem with the BBS 01/02 motors are the torque just comes in bang from zero rpm.
I just didn't like the harsh bang and grind of mistimed shifting on my first derailluer set up, that thin bendy chain asked to cope with forces way beyond what it was designed for.
My first Nu Vinchi set up was a 250w BBS 01with a manual cable shift the improvment was to me worthwhile, the twist shifting does stiffen if under full load but you soon learn to shift down before you motor is pulling hard under load.
Range on the bike with a 15 ah battery was about 25 miles in the quite hilly area I ride, so im not so sure the so called power losses it creates amount to much.What did become noticable was because it is a variable ratio I found myself hunting about for the cadence I wanted to pedal at, I got lucky in finding a Harmony autoshift kit on ebay.
The NuVinchi with the Harmony shifter is so nice and easy to use, I just set the cadence and enjoy the ride while the bike shifts gear to suit the speed/road conditions.
My girlfriends bike now has the BBS 01 Nu Vinchi harmony with upgraded controller to 350w for the steep hills she has to get up, altho if it was 250w I doubt she would really notice much difference.
I run the same setup with a BBS 02 48v more power but everything works the same seemless smooth shifting works great in stop and go traffic.
An inefficent bike thats quick and easy to ride.

Can you elaborate on the upgraded controller? I was contemplating haveing the rear sprocket changed in order to make going uphill easier but then I was told that this would affect the higher gears as well.
I keep hearing that there is no difference between the 250w and the 350w motors and the extra power is simply due to the controller allowing more juice. The can surely be no objection to allowing more power to assist hill climbing if the top speed is still limited to the legal maximum.

 

[Spotty dog]

Hi Mike,
Been awhile since I built my bikes I don't search net now for specs and info as I feel they are set up and running fine for our use.
The difference as I recall between the 250W and 350W 36v motor is the controller 15A for the 250W, 18A for the 350W.They didn't feel very much different to me, both my bikes use a replacement 42T chainring.My first gearing set up was 21T rear sprocket , this gave low gearing good to climb hills but I was flat out at about 20/22mph peddling like mad.
I now run the BBS 01 at 42T x 18T with 2.1 x 26 schwalbe marathon tyres the BBS 02 at 42T x 16T with 2.35 x 26 big apples tyres.
If you go to Sheldon Browns website the gear calculator will show you the gear range those ratios give you, I found these about right for the hills I climb and allowing sensible peddling cadence up to about 25mph on the BBS 01 and 30mph on my BBS02.
I prefer gear inches to percentages my lowest ratio on the BBS02 is about 35" rising to about 120" in high for me this is suitable for my riding needs.

 

[Mike45]

Hi Mike,
Been awhile since I built my bikes I don't search net now for specs and info as I feel they are set up and running fine for our use.
The difference as I recall between the 250W and 350W 36v motor is the controller 15A for the 250W, 18A for the 350W.They didn't feel very much different to me, both my bikes use a replacement 42T chainring.My first gearing set up was 21T rear sprocket , this gave low gearing good to climb hills but I was flat out at about 20/22mph peddling like mad.
I now run the BBS 01 at 42T x 18T with 2.1 x 26 schwalbe marathon tyres the BBS 02 at 42T x 16T with 2.35 x 26 big apples tyres.
If you go to Sheldon Browns website the gear calculator will show you the gear range those ratios give you, I found these about right for the hills I climb and allowing sensible peddling cadence up to about 25mph on the BBS 01 and 30mph on my BBS02.
I prefer gear inches to percentages my lowest ratio on the BBS02 is about 35" rising to about 120" in high for me this is suitable for my riding needs.

Thanks for this information. I will have to wait for trying the bike on my local hills before deciding on whether to change the rear sprocket. I don't suppose it will be possible to change the controller now that the sale has gone through, even if the seller was amenable.

 

[Spotty dog]

No harm in asking the question but I found the difference quite small to the point I wondered if the upgraded controller I got from EM3ev was in fact a 250W 15A controller.
Using Sheldon browns gear calculator gives you a good idea of the effects of changing sprockets will be, I use shorter 165mm cranks, the calculator also includes crank length in its calculation.
I would add about stiff shifting under load with the manual N360, I found twisting the shifter tiny amounts rather than one large turn for a lower gear worked better, good luck with your bike.

 

[Mike45]

No harm in asking the question but I found the difference quite small to the point I wondered if the upgraded controller I got from EM3ev was in fact a 250W 15A controller.
Using Sheldon browns gear calculator gives you a good idea of the effects of changing sprockets will be, I use shorter 165mm cranks, the calculator also includes crank length in its calculation.
I would add about stiff shifting under load with the manual N360, I found twisting the shifter tiny amounts rather than one large turn for a lower gear worked better, good luck with your bike.

Fortunately I have got the fully auto hub which obviates the need to change manually, although I found that I had to select manual to get the slightly lower gear that is available in manual in order to get up Park Street.

 

[Spotty dog]

I have not had that problem have you tried recalibrating the gear shift.
Is also worth downloading the NuVinchi software setup web page to your pc.
It will allow you to input via the micro usb the changed sprocket sizes on your bike and other stuff like the time delay before going to sleep mode and even modulation of the gear shift to a stepped change if u prefer the feel of it.
They also upgrade the operating software from time to time worth going on to check u have the latest version.

 

[Mike45]

I have not had that problem have you tried recalibrating the gear shift.
Is also worth downloading the NuVinchi software setup web page to your pc.
It will allow you to input via the micro usb the changed sprocket sizes on your bike and other stuff like the time delay before going to sleep mode and even modulation of the gear shift to a stepped change if u prefer the feel of it.
They also upgrade the operating software from time to time worth going on to check u have the latest version.

The bike hasn't been delivered yet so I haven't had time to tinker. Will know more next week.

 

[Spotty dog]

Happy tinkering am sure you will find it a very pleasant bike to ride.

 

[Siddie]

I am looking for a step through bike that will get me up the local hills here in Torquay with a moderate amount of pedalling. That rules out the Rapide and the Tornado. The Sonata is fairly small and limited to 100kg, I am 6ft 1 1/2in tall and weigh 110kg, so no go there.

My short list includes the KTM Macina NuVinci Plus, the Kalkhoff Ergo Impulse XXL i360 and the Agattu Premium i360 Harmony. Having studied the posts in this Forum I am concerned re the reliability of the Impulse motor. By comparison, the Bosch motors are less powerfull and have much smaller batteries. The Panasonic motor also appears to be less powerfull and I have not come across a step through bike with a Panasonic motor and a NuVinci hub.

The more that I research the problems I come across!

I am looking for a step through bike that will get me up the local hills here in Torquay with a moderate amount of pedalling. That rules out the Rapide and the Tornado. The Sonata is fairly small and limited to 100kg, I am 6ft 1 1/2in tall and weigh 110kg, so no go there.

My short list includes the KTM Macina NuVinci Plus, the Kalkhoff Ergo Impulse XXL i360 and the Agattu Premium i360 Harmony. Having studied the posts in this Forum I am concerned re the reliability of the Impulse motor. By comparison, the Bosch motors are less powerfull and have much smaller batteries. The Panasonic motor also appears to be less powerfull and I have not come across a step through bike with a Panasonic motor and a NuVinci hub.

The more that I research the problems I come across!

the Agattu premium i360 Harmony is heavy and does NOT have a very good climb assist. In truth it is extremely hard work! In my opinion NOT suitable for the hills in South Devon.

 

[Mike45]

the Agattu premium i360 Harmony is heavy and does NOT have a very good climb assist. In truth it is extremely hard work! In my opinion NOT suitable for the hills in South Devon.

I have ended up with the Kalkhoff Ergo Impulse XXL i360 mainly because the company selling the KTM didn't seem very interested in selling me a bike! The Kalkhoff is very heavy and it would get me up the hills if it weren't for the fact that my legs aren't what they used to be. When they give up the ghost I stop and rest for a minute or two and then start off again.

What I can't understand is why, when I start off again, the bike seems to produce more power for a short period. If it kept on producing that level of power I would probably be able to cycle non stop to the top of the hill.