motorapido

I will be building up a touring bike with a front dynamo hub (Shutter Precision), with power feeding into a Sinewave Cycles USB power converter unit. I will be running an Alfine 11 internal gear hub, for which Shimano makes a Di2 unit. I am converting a compact double crank into a 1x setup, and ditching my front derailleur. It seems logical to me that I should cobble together a connection from the Sinewave USB unit to the battery for the Di2 unit, so that I am never without Di2 battery power if I decide to hit the road for a crazy-long tour and don't want to plug in to a power outlet to recharge the Di2 battery. I believe that there are retrofit batteries on the market with a USB power input designed to power di2 units. Has anybody yet built up a bike using a Sinewave USB charger or similar unit to keep their Di2 better charged/topped-up? If not, I guess I need to document my build and share what I learn.

For starters, I scored one of the last pairs of Versa shifters left on anybody's shelf (out of production by Versa, I am told, but I found a pair at a UK shop) since I run drop bars. If I end up not liking them, then I will switch to the Di2 unit to shift the Alfine hub. I use Nashbar rebadged Microshift shifters now for my 2x10 setup, and i like them quite a bit. i am told that the Versa 11 shifter is simply a rebranded Microshift unit with a different internal gear mechanism to match the Alfine 11. I wonder in the long run which would be more reliable and robust on a long tour -- the Versa shifters or the Di2 unit? Hmm. Deep down, I like the idea of mechanical things more than electronic things for reliability. But since you can't just walk into any bike shop in the middle of nowhere and buy a replacement Versa shifter or fix its internal parts, maybe a Di2 would be more trustworthy. I had considered mounting a little accessory mount bar off the stem to use the Shimano trigger shifter for the Alfine, but I don't like that idea very much. I admit that idea would probably be the most reliable and road-fixable of the solutions, compared to the Versa shifters or the Di2.

Thoughts?

fietsbob

Done any Homework , first? Know the voltage /amperage load requirements that the Di2 battery supplies . read your Di2 manual?


standard output of most Bike Dynamos is 6v,3w. (AC output is what I've seen on an Oscilloscope )

I thought they Shimano tried an easy shifting cruiser bike like that hub put out some power to make the hub shift, It was a bit of a Flop.



A British cycle-tourist passed down the coast last summer they had an versa/Alfine 11 speed setup . seemed to br working Fine..

they serving ground Puxatawny Philburgers yet in PA?

motorapido

Yes. I have studied up on it. Sure, the dynamo hub puts out ac power, and the Sinewave Cycles unit converts it to DC with a USB output, yielding a regulated supply of AC charging power for cell phones, GPS, Kindle -- pretty much anything that requires USB charging. You can find Di2 batteries with a USB charge input port, so the fact that nobody seems to have posted details of a build that supplies recharging power to a Di2 unit through a Sinewave Cycles USB charger (or similar unit, like The Plug, or Busch and Muller USB Werk) driven by a dynamo hub somewhat surprises me. The Sinewave USB charger units are said to be all but bombproof and ultra sealed against wet conditions, and something tells me a Di2 unit might be more field reliable than the Versa shifters. I am told that the Alfine 11 shifts more reliably and consistently with the Di2 unit than with the mechanical shifter units on the market -- whether Shimano or aftermarket. Dunno. Just thinking it through and wondering if anybody has field test such a setup.

About Punxatawny Phil, the groundhog of Groundhog Day, I work for a company that does a lot of business in that area, and I have met many people who have been part of that oddball tradition. We Pennsylvanians are quirky people.

motorapido

A valid response to my post would be, "Who the heck would depart from reliable, tried and true derailleur gearing for an IGH on a touring bike, and on top of it, who would introduce electronic shifting in place of tried and true mechanical shifting." I understand and respect such a position. When I bought my car and learned that it did not have an oil dipstick but instead relies entirely on an electronic oil level sensor, I thought, "There is an electronic solution to a non-existent mechanical problem. Why should I rely on an electronic oil level sensor when a good old dip stick is tried and true?" Then an old man pointed out to me that his father said something similar when hand-crank starting went away and was replaced with electric starters. Eventually the technology becomes reliable and the old mechanical way goes away. We probably are not there yet for touring bikes, but as a lover of new gear and electronic advancements, I am curious about the concept of dynamo-charged Di2 shifting of an IGH for touring.

fietsbob

just sayin... I Have a Rohloff . its already got an extensive touring cyclists user list over the many years they have been produced..

It has as its back up shifter, should a common Gear cable Break, using an 8mm wrench directly on the end of the sequencing Cam...


Electronics? there is an Australian company replaces the 2 cable rotary shifter on the Hub, with a servo Motor. (I'm fine with the stock Gripshifter)


maybe somone knows the load demand for the Di2 Controller

if it were : Max. voltage 5.00±0.25 V (pre-3.0); 5.00+0.25-0.55 V (USB 3.0)


Max. current 0.5–0.9 A (general); 5 A (charging devices)

(The USB standard, from wikipedia) .. That would be convenient.

squirtdad

Question for OP....not directly related

You noted that the dynamo puts out AC current? That seems odd, unless I am recalling what knew about generators incorrectly?

ok belay that..... I did a search and it seems that dynamo hubs are not generators, but magnetos and magnetos generate AC. Anybody know why magnetos are used


OK, I guess my question is why do this, only because it seems overly complicated unless you are touring so far away from civilization that you won't have power....and in that case I think I would want mechanical shifting.

all is all it sounds interesting....post pics when done.

motorapido

Interesting. Leave it to the Germans to offer a back-up mechanical option in case the shifters break. Brilliant. Too bad I was too cheap to shell out the extra for the Rohloff. The extra weight and tales of a bit of noise and more inefficiency allowed me to explain away my cheapness for more objective excuses.

motorapido

What I propose makes no practical sense if outback touring reliability is the highest objective. I realize that. I just become obsessed with new gear and modifying things and trying setups that haven't been done. I went through a lengthy phase of modifying early 1960s Vespas into very quick kitted street screamers with all manner of modification go-fast parts. I did the same with other vintage two-stroke motorcycles, including amassing my own metal shop to lathe and mill and cast and machine custom parts if I could not find the parts that I wanted. It makes no sense at all, but is sure is fun.

Powering a Di2 battery with USB output from a dynamo hub seems far less useless and far more reliable than my old two-stroke engine modification obsession. So I am seriously considering it.

squirtdad

Quieter at least

hueyhoolihan

sounds interesting, apparently nobody else has found reason to do it. but it sounds like it's worth giving a try. let us know how it goes.

Bezalel

Reliability, there are no brushes to wear out or get contaminated. Also when they were first developed, they were used to power incandescent lights, not electronic circuitry so AC was just as good as DC.

dsbrantjr

USB power is 5 volts DC, not AC.

Mr IGH

It's a semantic thing, spanner, wrench. A hub dyno is a permanent magnet generator. The Brits call that a magneto, we call it a generator. Sturmey called it a dynamo because they had marketing even back then...sounds like a power plant!

Shimagnolo

Try telling that to any US aircraft mechanic.
Small piston aircraft have two magnetos that operate *only* the dual ignition systems.
There is a separate generator that operates the the electrical system for instruments, lighting, etc.

"Aircraft engines, where keeping the ignition independent of the rest of the electrical system ensures that the engine will keep running in the event of or battery failure. For redundancy purposes, virtually all piston engine aircraft are fitted with two magneto systems, each supplying power to one of two spark plugs in each cylinder."

Source: Magneto - Wikipedia, the free encyclopedia

motorapido

Keyboard error. Yes, DC output from Sinewave USB/dynamo converter unit, for sure. Mitten-hands, due to frigid Central Pennsylvania weather.

Mr IGH

That's an ignition magneto, it is a permanent magnet device just as a generator is. The question/point was; what is hub power generator device, is it a generator or magneto? Answer; both, the term is interchangeable and is a historical artifact from the classic Brit/USA terms difference.

Before cars had alternators, permanent magnet device were used to generator electrical power, the Brits call them magnetos, we called them generators. The term is interchangeable (like spanner and wrench), but since cars haven't generators for several decades it's become a moot point.

FWIW, in an alternator the magnetic field is generated by the field coil (it's an electromagnet instead of permanent) and is modulated by the field coil current to regulate output. Much better for cars, too complex for a bicycle.

FBinNY 

Brushless, no moving parts design. Moving magnets with a stationary coil. Simple and effective for the purpose intended, but AC by nature.

Juha

My 0,02€: If the Di2 battery can be charged via USB (0,5A), why not get two batteries? One is in use while the other is charging.

davidad

Busch & Müller USB-WERK Charger

fietsbob

& FWIW, both AXA, of NL and B&M of Germany put the Converter USB jack in a Headlight Model.

RomansFiveEight

So my question is, why is it necessary? Don't get me wrong I'm all for ingenuity. But it's my understanding that for most folks the Di2 system is lasting sometimes thousands of miles. Folks going months and months before getting any sort of indication that it's time to charge. I get that you're touring but are you really away from power so much that you can't charge it once every couple of months?

If that IS the case, then I'd second the above suggestion of a second battery with a USB charger. Or; maybe even just a second battery thrown in a bag. Actually, that's probably not a bad idea ANYWAY for touring. For redundancies sake (as batteries do fail even if they didn't fail from discharging)

davidad

Found another in Adventure Cycling mag. Sinewave Cycles | Sinewave Cycles

daveeasa

Any update here? I was thinking of doing something similar, for my commuter, and for the same lack of reason, just because I'm too lazy to plug it in to charge as I hang my bikes from the ceiling.

daveeasa

This setup crossed my mind.

Alternatively, however, a low w-h battery which is smaller/lighter than the regular external battery might be ideal for this design. Perhaps even a simple capacitor, which effectively would require some pedaling before a shift can occur. That would be horrible for an internal gear hub such as the OP plans to use which can be shifted while stopped, but wouldn't be completely out of line for a touring setup where you would be in motion when you shift.

It sort of depends on how many revolutions it'd take to charge enough to support a few shifts. Basic experience with my dynamo and led light suggests the chances of not having enough power to shift as desired would be minimal.

Not that weight really matters when touring, but battery durability is something to think about, as well as earth impact. Then again, I'm not sure that we have many examples of capacitor usage for temporary storage. I do know my supernova e3 first generation standlight doesn't work nearly as well as it did when new, but perhaps they have improved on that in recent iterations.

fietsbob

Hire an electrician [IBEW], to put an electric, mains outlet, up where you hang your bike.