inside the nuvinci hub

[wdbtchr]

Hmmm, wonder why you guys are having so much trouble. I just used the standard Park tool, 8 spline if I remember correctly with the hex head on it. Plain old 1/2 in pneumatic rattle wrench....zipped right off.

One other interesting thing (to me at least) is the performance in the cold. I was anticipating a lot of drag in the cold. So far it has seen a low of 2 degrees F. Sitting out over night I just started the engine and drove off. No muss no fuss. I did have an instance where the shifter sleeve froze from ice accumulation, but just kind of scraped it off and it worked. I only have about 1600 miles on it behind a Titan, but it has worked flawlessly so far. I haven't babied it either...not down right abuse, but it has earned it keep...heavy bike, pulling a trailer, steep hills, even some serious snow berm jumping and spinning through heavy snow. just keeps going.

One feature I don't have is the auto shift Kc has. Sounds like quite the setup. I will be interested in updates as time goes on. Thanks.

 

[Goat Herder]

The nut is a integral part of the free wheel if'n my free wheel goes bad? If I got to? I will destroy it getting it off. Free wheel being bad any way. But mine is working peachy so far.

The replacement a common free wheel will have a new threaded nut with it.

 

[KCvale]

NuVinci is top notch, they shipped me off a new controller board today, no charge.

The really REALLY cool part about the Dev Kit hub besides it's auto-shifting is you can program the controller on your PC with their software to set up to 10 custom 'shift maps' you can select on the fly from the Remote Display, or 2 you can toggle between with just a simple on/off switch.

For the main entry screens it just uses Macros for Excel Speedsheet.
This a print screen of the 2 key entry screens.

The keys here are the drive and hub sprocket sizes in the first entry section of course, but also the desired 'sweet spot' input RPM for actually creating the maps in the second section.

The program will then fill in the hub shift points, 23-977 uesable, for each increment of MPH you care to use and are traveling which the hubs own sensor sends to the controller and why you also have to enter the wheel circumference.

Well, to that I need a Tach readout of the freewheel hub in operation so I can ride and measure the motors 'sweet spot' RPM range to use.

I posted in detail about how to do this with a $20 bicycle digital speedometer in the 'Tach from a Bicycle Speedomoter' topic already here, but for any Jackshafted bike you get the motor RPM by these simple steps.

1. Attach the magnet that would normally go on a wheel spoke to the inside of the inner freewheel pedal sprocket.
2. Attach the the pickup sensor on the frame within a couple of millimeters of where the magnet spins by.
3. Set the Speedo's tire circumference to 1742mm if using the stock JS kit gears and stock 10 tooth motor sprocket as the 'magic number'.

Your bike speedo/computer MPH readout will display RPM in 100's.
For example 51 MPH would actually be 5100 motor RPM.

If you use the Schwinn speedo from Wally for $19 delivered it has 1/10's of MPH was well, so 51.2 MPH would be 5120 RPM.
Walmart.com: Bell Sports FreeFit 15-Function Wireless Computer: Bikes & Riding Toys

For you stock kit direct drive guys it's even easier.

With the stock 10 tooth motor and 44 tooth wheel sprocket just mount your speedo like a speedo on the wheel, then enter 1179.2mm wheel size as the 'magic number'.

You can read that other topic here for the actual math if you use different size sprockets or gears and calculate it yourself, but the base 'magic number' is 268mm to make a speedo in MPH mode act as a tach in x100 regardless of shaft size.

As an 'extra added super double bonus' as the old TV commercials used to say, you can use the other bike computer features as well.
For example the non-resettable odometer number as an Operation Hours number, just divide by 60.
You can also display average RPM, etc.

Average and Max motor RPM might come in handy actually.
You could use that number to tune an Xchamber for example.

It might come in handy for new motor break-in as well.
For example you could get readout of what actual 'take it easy for x amount of time' really is for a new motor on any given bike, and use the tach to keep it under xRPM for xMotor Operation time.

All just thoughts but for ~$20 it sure as heck beats anything I could find. I found a dedicated motorcycle tach that tapped the spark plug wire for $50 +S&H, and motorcycle Speedo/Tachs started over $100 and went up dramatically!

 

[timboellner]

You must have put some time in on this one.
How can you calculate engine rpm on a multispeed jackshafted
application when you have used wheel speed converted to engine rpm?
I could be in 5th gear going 20 mph, or 3rd gear screaming at 20mph ? Maybe I missed something you explained.
Anyway here's a good tach for cheap:
tt151

 

[KCvale]

You must have put some time in on this one.
...Maybe I missed something you explained.
Anyway here's a good tach for cheap:
tt151

Ya, I have a couple hours into it so far, a couple more to go too ;-}
I looked at that tach, it's inductance on the spark plug wire and won't give me what I need anyway.
The detail about the Speedo as a Tach on a Jackshaft is in the post above.

It worked out well.

The sprocket holes for both sprockets line up so I could put screw though, and the magnet side mount of the spoke setup fit right in perfect.

I have the bike computer programed but I need to make the wire longer so it mounts back up on the handlebars.
It works, but I haven't taken it for a ride yet to see how well.

What this will give me is the number I need, the hub's input RPM for the hub controller programing software, and I can ride it around to find this motors 'sweet spot' to use under real riding conditions.

I was going to go ahead and get new speedo for the bike too but then it dawned on me I don't need one, the hubs Remote Display has one.

All in good time and when it warms back up, it's 20 degrees below normal here today, mid 40's.
I live in the desert for a reason, the cold and I don't get along well ;-}

 

[decoherence]

i've been wanting a nuvinci hub. now i want to save up for the developmental one!
looks like i'm going to try & scrape together for the approximate 1k for the drive train.
$595 for the nuvunci dev. hub.
$250 sick bike parts jackshaft HD.
then the rst of the assorted parts. 12v battery, strong axle, speedo, & bits+bobs.

the other night i was trying to think of how to make a trike w/one on each of the rear wheels or as jackshafts since they don't make left drive hubs.
possibly even manipulating the 2 controllers to be electronic differentials.
turning the handlebars to the left would make the left hub drop to a lower gear depending on how far the the handlebars are turned.
if the gear is already in the lowest the right one would do to a higher gear.
theoreticly you could run a higher hp engine since it would be divide the power between the 2 of them.
ie: the morini franco S6-C competition is 11.4hp.
each hub can take a sustained 7hp but they would only end up receiving 5.7 @ the most.
i know it is a convoluted idea.
you may say I'm a dreamer, but I'm not the only one.

 

[KCvale]

I just got it buttoned up and running yesterday.

The 12V SLA battery, controller, and AC/DC converter for the 'Hub Rub' dyno is in the metal box, which is bolted to the rack.
Note I used the ribbed cap of a 2-stoke motor oil bottle for the dyno wheel, it lines up perfect with the ribbed band on the Kenda tire.
I'll replace it with a black one when buy oil again.

A lighted power on switch for the controller and the Remote Control/Display are mounted on the handlebars.

I have 2 new shift maps programmed in so far, I can have 10, and can change shift maps and toggle back and forth to manual shift from the Remote Display on the fly.

It is almost eerie to ride...
It takes off and reaches ideal motor RPM at about 6MPH and stays there as speed just keeps increasing with no discernible change of gears.

The only way I know it's shifting is to watch the shift position readout on the Remote Display fly by from 23 to 977.
The motor is new so I've kept it under 30MPH and taking it easy, but after this tank of gas she's getting an Expansion Chamber to help out because it is a VERY heavy bike.

I will get to the wiring and the inside of the 'black box' later.
I still need a switch for the 12V halogen headlight and I am going to re-do my Ignition Keylock and wiring for that too to clean it up.

Finally it is getting some paint touch-up and then some tan accent paint, and if I can, my removable old style wood crate for the back for cargo room.

 

[LI-ghtcycle]

Oh wow am I in heaven?!?!!!

First you guys hook me up with the amazing multi-stage gear calc, and now you have the ear of one of Falbrook's Dev's for the Nuvinci!!!!!

I have a "used" one in the box never installed that is just missing the "C" clip to secure the freewheel adaptor, and need to run a double freewheel for RH drive (on pedal one motor) this will be with an electric motor pushing much milder power, about 1300 Watt, or 2HP roughly, and I was concerned this would be too much load for the N171B !! I am so glad to hear it is not!

I plan on using the inner freewheel with a #25 chain, 80T sprocket attached to a freewheel such as listed here:

TNC Scooters (Scooter Sales and Service)

If my calculations are correct, I will be using a 11T sprocket on my Turnigy 63 - 74 200Kv RC motor, turning at 2960 RPM's, and this 7.2 to 1 reduction should be good for a no-load speed of 31 MPH at the rear wheel (26 x 2.3 inch), and that should translate to around 25 MPH on the road, and around 15 -20 MPH up a 10% grade with out the motor breaking a sweat, especially since the N171 will be getting the gearing just right for the motor.

My question is however, if there is anyway other than using something like a rear derailler held in the middle position (or some other chain idler if applicable) and use a front derailler and a 3 ring 5 bolt crank.

I like to pedal, just not to haul a 150 lb touring bike fully loaded for a West to East coast trip this spring, with just my Gulf War Syndrome legs alone up a 15% grade! ;-P

How could I try to match my pedaling cadence with the motor? I'm not looking to just have my legs hang-out either, as pedaling a bike is the best therapy so far for my GWS to date, just that the associated fatigue could side-line me with out a motor that can pretty much do the whole job for me if needed.

Maybe I just need to get close with the front derailler and suffer through?

Thanks!

 

[KCvale]

Oh wow am I in heaven?!?!!!

First you guys hook me up with the amazing multi-stage gear calc, and now you have the ear of one of Falbrook's Dev's for the Nuvinci!!!!!

That MODEL N171B NuVinci®CVP looks like great hub for you.

You can 'pedal along' with a standard jackshaft, but there is no friction.
Putting a second sprocket with derailer is not as easy as it sounds.

On a jackshaft the motor sprocket and back wheel drive sprockets are locked to the freewheel. It is just the pedal crank that freewheels.

Altering the front pedal sprocket would alter the whole drive to the wheel.
The only way to pedal at a different RPM than the motor to back wheel drive sprocket is to gear your pedal crank itself.

 

[LI-ghtcycle]

That MODEL N171B NuVinci®CVP looks like great hub for you.

You can 'pedal along' with a standard jackshaft, but there is no friction.
Putting a second sprocket with derailer is not as easy as it sounds.

On a jackshaft the motor sprocket and back wheel drive sprockets are locked to the freewheel. It is just the pedal crank that freewheels.

Altering the front pedal sprocket would alter the whole drive to the wheel.
The only way to pedal at a different RPM than the motor to back wheel drive sprocket is to gear your pedal crank itself.

Right, so if I have the double freewheel (two freewheels stacked, one for the #25 Chain single stage reduction, no jack shaft) with the 80T freewheeled sprocket inboard, and the pedal chain outboard (single speed pedal freewheel) wouldn't I be able to use a front 5 bolt MTB triple chain ring to at least get close, I have pedal bikes that are geared so that I can be pedaling hard up to 40+ going down a long steep hill locally. I would only be using a rear derailler to take up the slack, I could just use a chain guide for single speed, I suppose, but I'm trying to keep logistics and costs down to a minimum, and hope to use as close to off the shelf common items found in either a local bike shop or scooter shop in the case of the #25 chain & sprockets.

 

[KCvale]

Are you talking 2 chains to the back wheel?
I just can't follow your plan with words, draw us picture ;-}

 

[GearNut]

TNC Scooters (Scooter Sales and Service)

Sorry, off topic but noteworthy.
My DLink firewall flagged the site in this link as a known phishing site.

Now back to your regularly scheduled thread.

 

[LI-ghtcycle]

Are you talking 2 chains to the back wheel?
I just can't follow your plan with words, draw us picture ;-}

Yes sorry, I forget sometimes the ideas in my head are not always that clear in text!

Here is a pic of what one guy has done to accomplish this (I'll be using the scooter freewheel and #25 chain however, not the t8f he has or his custom bracketry)

Here is the link to how he accomplished it, however, I hear that there is some form of adapter that is a normal "bolt on" part sold by nuvinici to accomplish the same idea.

Endless-sphere.com • View topic - new-old build

I'm hoping it's the ladder since I want to use as much off the shelf bolt on stuff as possible, no sense in going on a coast to coast trip with one-off parts that only a machinist can make for me. (plus I'm not rich!)

 

[LI-ghtcycle]

Sorry, off topic but noteworthy.
My DLink firewall flagged the site in this link as a known phishing site.

Now back to your regularly scheduled thread.

Whoa! I hope your firewall is wrong, a local electric bike shop orders on this site all the time!

 

[KCvale]

Hmm not sure what that endless sphere site is, but it's not working, and this forum is trying to contact it to name the link to it and caught in it's own endless sphere trying to according to my browser status bar as soon as you hit this page of posts.

Handy forum gizmo unless it doesn't time out and quit trying if the site won't answer.

Anyway, back to the Developers Kit Nuvinci Hub...

A lot of people I talk to can't seem to grasp how it works in way of a direct relation to something else so I came with an analogy to compare it to a regular old multi-sprocket rear derailer bike.

For the math lets just use a single front pedal sprocket, which all you get with a JackShaft drive anyway, and a 5-speed rear derailer.

And I will use the the hubs working NuVinci gear ratio that ranges from .5 to 1.8 gear ratio RPM to pedal and motor input input RPM.

The NuVinci CVPT replaces derailleurs and internally-geared hubs, and provides a gear ratio range of about 3.5:1, similar to that on bicycles with 8 or 9-speed hub gears, or with double chain rings (most racing or fast road bicycles).

This range is somewhat less than the 5:1 ratio found on bicycles with a Rohloff 14-speed hub gear or most mountain/hybrid/touring bicycles with triple chainrings.

That said, lets just say that 10 non-redundant gear ratio options is all you you get between the lowest gear ratio (giant rear sprocket, small front sprocket) to the highest overdrive gear ratio (tiny rear sprocket, giant front sprocket).

This is due to the chain itself.
Just one tooth makes a big difference when the drive is a fixed sized chain.

To compare how a CVTP works if it were a deraler with multiple cartridge sprockets you would have to picture using a chain with links like a delicate necklace chain, and a cartridge with 950 sprockets each larger or smaller by one tiny tooth that would mesh with each tiny link in the chain to cover that same gearing ratio you get 10 choices with on a bike.

And it gets better...

The only actual gears and chains in the whole drive is the 36 tooth drive chainring, the 18 tooth hub sprocket, and the bicycle chain that connects them.

Everything else is done inside the hub itself.
How it works is a lesson in fluid dynamics and complex planetary gear theory itself.

The input force (18 tooth sprocket) and output force (the wheel) never actually come come into physical contact like a mechanical multiple speed hub.
Suffice to say the 'magic fluid' inside hub does it depending where, and at what angle, the balls pass by the hubs inner wheel.

OK, all that said, the very best of the programmable Developers Kit electronically driven automatic hub I have now.

Again just to round things out, I can choose exactly which of those 950 tiny toothed gears (called Shift Points) I want to use at a given MPH, 1/2 a mile per hour at a time.
So to go from 0 to 40 MPH I can use 80 gear changes from as low as where I choose to start, to as high I care to stop.

Just because I can go from a full 50% reduction in input RPM under-drive to wheel at the lowest Shift Point of 25, to a 180% increase in input RPM to wheel over-drive at the highest Shift Point of 975 doesn't mean I HAVE to use the whole range.

That very thing is what has been making this programing multiple Shift Tables, which in itself is just a group for Shift Points for a given Shift Map of gear ranges I can choose on the fly.

For example, the lowest Shift Position of 25 is like having a 72 tooth rear cartridge sprocket to the 36 tooth drive chainring.

Ya, like I need that.
The same goes for a Shift Position of 975 is like having a rear sprocket with just 3/4 of one tooth to the 38 tooth drive chainring.
Or to make more sense, an 18 tooth pedal chainring and a 36 tooth cartridge sprocket.

Can you imagine trying to move your bike pedaling to make your wheel move nearly two full rotations one a single pedal rotation?

They have uses, especially over-drive when you have speed and momentum.

For the most part it is keeping the motor at the RPM you want for a given change of speeds from dead stop to top comfortable speed.

One last note before your eyes totally glaze over...

Unlike my derailer analogy of this hub to a 950 gear derailer, there is no chain movement or loss of input power to the wheel.
As the computer controlled stepper motor turns the hub shaft that moves the balls they change ratio in a literally microscopic fluid continuous motion without even loosing it's 'magic bond' to the wheel.

Once you can wrap your head around that you are on your way.

PS, quick note...
You should remove that endless sphere link, I just spent 45 minutes typing this and this site is still trying to connect to it.

 

[LI-ghtcycle]

Not sure why it should give anyone a problem, maybe it's the browser? I use Firefox and Chrome mostly, never a problem connecting.

There are a few of us here from Endless Sphere too (KiM, Thud and a few others I haven't seen yet I imagine) so I can tell you there isn't a problem with ES's site.

 

[spad4me]

I purchased a nu vinci hub and have not laced it to a wheel YET.
I keep my eye on this thread.
I have tried the double freewheel threaded setup . For me it peels all the threads off both the wheel hub and the freewheel if the freewheel is not threaded all the way in.
Not content to mess up just one wheel freewheel setup .
I bought another wheel and all the parts to do a double freewheel setup, and epoxied the thing together. It just took longer to peel all the threads off .
Maybe just 750 watts or so .
I used a 3 hp engine way to much power for this setup.

As for you're computer trying to connect to Endless sphere .
It sounds like a hosts file is blocking you

see here

Blocking Unwanted Parasites with a Hosts File

I use this one to remove most web based pests.
I can go to most normal places.
But not to places that are Dangerous to a WinDoze user.

 

[mbuna420]

Just read this whole post and thought this might be here but twas not so I thought I would share hope it helps some visualize how these hubs work

YouTube - NuVinci Bicycle CVT

 

[KCvale]

Re: inside the nuvinci hub And the Harmony

Well, here we are almost a year since I built my NuVinci DEV Kit automatic hub bike.
It has since been converted to manual and it has several hundred miles on now.

The auto hub didn't hold up very long with my high performance 66cc motor but now I think I know why.

First off, the DEV Kit auto hub is based on the older N171 hub.
They have dropped the price from $600 to $150, pretty cheap for a NuVinci.
Info here: Fallbrook Technologies

What was added to the text was this:

"If an internal combustion engine of any type is used with the Developer Kit, a cush drive system must be installed between the engine and the CVP to dampen out power pulses from piston acceleration, otherwise internal components can fail prematurely"

Well, I didn't use a 'cush drive' system, whatever that is, but still...

The reason for the big price drop appears to be the announcement last week of the new Harmony Auto/Manual shift hub based on the new N360.
Info here: Fallbrook Technologies

It is due out next year and really looks like they listened to what the gas powered bike builders like me said about the first generation hub and re-did the whole thing.

Opposed to an external controller, several cables, a huge electric motor to change the 'gears' attached to the outside of the chainstay and extremely fragile remote control/display, this new model uses a box about the size of the little 360's, and the controller is in it.
All shifting is 'fly by wire' either manual or auto, and all you need to use it is a 12-36VDC power source.

Inside sources have told me it is aimed squarely at the European electric bike market, but kept the gas powered market in mind this time.

For those of you in Las Vegas you might want to visit the Interbike bicycle show the 13th thru 15th, NuVinci will be there with all the info on the Harmony and some demo rides with it.
If I could swing the time I'd make the drive from Phoenix for it but no go this month.

With a little luck NuVinci may send me one for free testing like they did the original DEV kit hub.
I sure hope so. I have built 10 jackshafted bikes so far, 1 with the DEV kit NuVinci, and 3 with the older N170 manual hub that came on the Cadillac Fleetwood bikes.

Speaking of those Caddy bikes, I snagged the last new $300 one and expect it today for another JS job, but this time the wheels will go on a Felt 1903 bike.

But I wander hehehe...
The point is you can get a DEV kit for $150 now, and the new Harmony looks to be awesome.

 

[decoherence]

OMG! thank you for updating us!.
i read this thread before but i will reread it sometime today.
also thanx for the info on upcoming stuff.

in florida mopeds are not allowed to have "gears".
i don't know if that would include a manual nuvinci. i know that a DEV one work legally to the letter & intention. so i have been wanting one but was worried about it breaking.

i really wish they would make a kit to use instead of a variator on scooters.

also i was thinking some sort of system to help cushion the drive system for a while.
i found this, https://secure.wikimedia.org/wikipedia/en/wiki/Cush_drive
nuvinci should offer them for sale.