Electric-assist?

Second the motion. I have electric-assisted Vitesse 7 and like this very much. Still can get exercise but get there quicker, less swetted up.

The Freedom-ebikes kit is only 3.2 kg. This is practical for such a light-weight bicycle. The other kits, maybe prettier packages, are 6-7 kg which make little sense for a 12kg bike. The battery may be smaller than some but if more range be needed, there is the option of buying a second 1kg battery for use in parallel or (as Trek recommends--much cheaper) a second charger to keep at work. One only needs to widen the fork a bit (steel-only!) to fit the wider wheel with hub-motor. The motor has a freewheel so the bike rides as it was when motor is not being used.

Of course, a bike built for assist, has more options such as more standard-width forks for hub-motors or a chain drive (some argue more efficient over wider speed ranges) such as on the Boost. While built-in electric bikes tend to be single-speed or maybe 3 gears, I like having all 7 on my Vitesse. There is no law I have to use the motor all the time and I can still get up the hill on pedal power if I choose (or if the battery is empty).

Warning this response refers to another brand of electric bicycle but is not an endorsement and certainly does not suggest that Tern will not market a better product when they offer pedelecs! I know Tern's will be better.

Check out Prodeco Technologies. They appear to be using some DaHon patents for the frame, bars etc and they have OK components except they only have 24V to date. A 36V model is coming. [Correction they now have the Phantom X which offers 36V]. Keeping their price on most models under $1000 is brilliant. They will sell well. It even looks as if constructing a folder that could be "suitcased" might be feasible using the DaHon style fold.

I have built several PEDELECS and 36V is far superior. My personal pedelec used to get to work without being sweaty uses a Heinzmann, German front hub and pulse width modulated control. Works great. I actually use 38.5V of battery which increase my range about 4-5 miles to 25 miles.

www.prodecotech.com

http://www.youtube.com/watch?v=LP9xjnQXMR0&feature=related

I know the cunning guys and gals at Tern will do it better when they do market a electric assist product so it could be well worth waiting. Meanwhile a kit could get you by. Prodeco has them. I hope they offer 36V soon. Correction they now offer a 36V Phantom X

Rear hub would place the propulsion under your weight so should be better and would also integrate better with regenerative braking and "pedelec" schemes. However, this is more difficult to install and supply as an aftermarked kit. The cassette (no more room for hub-gears, etc.) must fit as well or be supplied with the kit. The chain drive, because of the lower speed range of the chain should yield better torque over a wider range of bike speed using the gears. However, such a motor needs be internally geared down, more weight, and installing this would be more difficult on a compact folder. Might be best idea for a designed-in bike if the weight can be kept within reason.

D... vehemently justifies their narrow fork and narrow hubs and their wheels are indeed a work of art. Admittedly, this restricts user upgrades.

Freedomebike motors have a freewheel so do not (should not) effect the bike when not in use. Kits incorporating regenerative braking make this much more complicated.

Electric motors work like this: They pull the most current and offer the most torque when ... locked (this is how they are often rated). Once the motor begins to turn (whether I turn it or the battery does), it also works as a generator, producing a current oposing the motion (Lenz's law, i.e. no perpetual motion). The faster it turns, the more Lenz's law current. So the actual current drawn by the motor and its torque decreases (why the chain drive can be better). At maximum speed, current drain is way down and so is torque. I have found, however, that my motor performs fine at most speeds I use.

To increase range, use less "throttle" and pedal! This way, the motor, if used, remains at lower speeds  for less time. I rarely use the motor on level ground except if I need a little more umph to get out of a spot quicker. This is an electric-assist for a bike, not an all-electric scooter (you can get these as well, but with much larger, heavier batteries). 13km in moderate usage is not an unreasonable range. Alternatives are to use an added battery (just 1kg but costly) or keep a spare charger at work (cheap).

This is pretty ingenious indeed! Limitations I see are that the motors which need be small also need to be internally geared for the slow revs. And since the batteries must also be contained, their size is quite limited.

Hi Josh,

sory to came back again, I hope you don't mind.

I just want to be sure you've noticed this ideea http://senseable.mit.edu/copenhagenwheel/

It seems very interesting for me - I don't know how it appears to you - and how feasible is the ideea.

But I've mentioned of some point (in a different topic) the ideea to change a wheel (and attach a battery) and voila - you have an electric.

The above ideea seems to follow (partially) this principle

Best regards

Hi Thor,

Thank you for notice so accurate what are the main problems of this project.

Of course I didn't expect for Josh or someone else to pick up an already made up fancy e-bike component and just add it to an already made bike. I just want to make Josh or someone else to think to other ways getting around. And maybe just to make the same e-thing better or more appealing. Of course - maybe I dare too much - but hey - this is just a try. I strongly believe that the future is not of those who want to keep walking to the same old paths - but for those who are willing to take new technological challenges and integrate in their products.

Even I can't afford (for the moment), I like Tern bikes a lot - they are a fresh air on the folding market - but as I said in a different topic, I would like much more a "convertible e - Tern bike". The above idea is just an idea going one step in a direction which it happens to like - and nothing more. By the way - it is possible to achieve a production license for it - so I believe that it's not just a cad drawing and an experiment. I believe that those who made the project have not thought to a particular bike (of course - folding bikes are not the intended target) like they said, cite: "It transforms ordinary bicycles quickly into hybrid e-bikes that also function as mobile sensing units". Since this is an already made project I believe that they overcome in one way or another - the problems you've just enumerated

There are many ideas out there - and probably most of them will never evolve in a production phase, since the profit rules. but looking in the past - some revolutionary idea like the plane, car and even bicycles - had their contestants at their time. Though ... looking at the present time we all have traveling with modern cars (and electric cars?), modern aircraft and beautifully (e) bikes.

Also - if you are looking to the bike market, almost every major player in the field has started entering in the e-bike field with some dedicated models - specially designed for electric assist. And not only - some car manufacturers have started to create (and sell in 2012?) - see Smart, Toyota, and Peugeot some e-bikes which complements their electric urban cars. I believe this trend will grow up in the future.

Of course - this is just an opinion - feel free to comment

All the best

I've noticed you're post script (bold) - this is the second time you are making some subtle remarks to the europe. See this topic: http://www.ternbicycles.com/forum/just-wish

where you said, cite:

"Winning a Eurobike award being an Euro Company .... is usually a little easier than just by merits alone".

Do you have a problem with euro zone? You know - there are many inventions discovered here in Europe

I just wondering

Regards

Thank you for clarification Josh.

I din't want to harm anyone with my observations

I'll look further for Tern bicycles

Best wishes