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Jeff writes -

Neodymics Cyclemotor is a self contained powered wheel designed to instantly replace the front wheel of any standard bicycle. Prototype is powered at 72 volts by four unmodified Dewalt nanophosphate packs using a reverse engineered drill speed control and optical relays.

Neodymics Cyclemotor electric bike conversion kit – Link.

Phillip Torrone

Editor at large – Make magazine. Creative director – Adafruit Industries, contributing editor – Popular Science. Previously: Founded – Hack-a-Day, how-to editor – Engadget, Director of product development – Fallon Worldwide, Technology Director – Braincraft.


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Comments

  1. amp2003 says:

    Scary looking, if for no other reason than the brakes alone. I’m not a big fan of how it captures the stock cable motion, and uses it to acuate the aux brake. Most of your braking comes from the front wheel, and the additional components would hurt the “feel” of the braking action and make it harder to modulate.

    I don’t want to sound like a doubting Thomas (too late), b/c it obviously looks like this person put a heck of a lot of time and effort in to it. It just looks like it lacks a certain amount of elegance.

    I’d be interested to see if the steering geometry was designed to mimic the response of the stock setup. Ie. caster, fork offset, etc. Looking at the pic above, I would think that this bike is steers slower due to the contact patch being behind the ‘king-pin’ axis. But with that mass up front, maybe that’s not a bad thing.

    Sorry, just thinking out loud.

  2. jswilson64 says:

    How could all that “instantly” replace anything? :-)

  3. CyclemotorEngineer says:

    amp2003 and jswilson64,

    Thank you both for the feedback.

    My intuitive sense is that the brake feels just as responsive as original. Cyclemotor brake must be adjusted for small rim-to-pad clearance, just as in original. Based on your comment, however, we will try to quantify by adding equivalent of Cyclemotor weight to a conventional bike measuring the stopping distances.

    Regarding elegance, the primary design goal was to make the Cyclemotor easy to install. A cool looking shroud may be added at some point before hitting the market. (I think it looks cool already, but of course am biased.)

    Trail was adjusted to eliminate shimmy. This device handles very well and installs in less time than it takes to put a bike on a car rack, as shown on our homepage videos.

  4. amp2003 says:

    How’s the steering on the bike, does it handle like the stock setup? It looks like your design puts the contact patch between the road and the tire further rearward than the standard wheel. By moving the front wheel forward slightly, you could get closer to the stock setup (I’ll try to find a pic of what I’m talking about). But like I said earlier, maybe slower steering is a better option for its intended use.

    Nice job on the suspension though. Speaking of which, would a suspension fork bind with this attached? If so, maybe an alt version could ditch the built in shock, and instead include a telescoping element that would allow the existing front shock to soak up the bumps.

  5. Stokes says:

    I think it looks pretty cool, too. I wonder, though: are the power tool battery packs cost effective? It seems like generic batteries would be cheaper, although they wouldn’t come in durable packaging and would need their own charger.

    How about a back rack for alternately carrying the Cyclemotor and normal front wheel? In the video, I saw the front wheel strapped to the back rack, but putting it on would still leave you with the motor to carry.

  6. amp2003 says:

    Found a pic. Wikipedia is calling the distance I’m refering to as ‘trail’

    http://en.wikipedia.org/wiki/Bicycle_and_motorcycle_geometry

  7. CyclemotorEngineer says:

    amp2003,

    Our first generation Cyclemotor included a wheel that was the same size as the stock setup. It had higher rotational inertia about the steering axis and wheel axle. Steering in this version was noticably slower than stock setup, but not pathalogically so. The low center of gravity on the steering column made it a stable ride. Photos of this first generation Cyclemotor are on the following page:
    http://www.neodymics.com/drawing.htm

    Current version of the Cyclemotor has lower rotational inertia about both of the above axis. We are replacing a 700C wheel with a 16 inch one. Steering of current version is very close to stock setup. Also, the low center of gravity gives a good margin of stability. Again, we ought to set up a course and quantify the comparison.

    Moving wheel fore and aft is what I meant by trail adjustment. The trailing links have horizontal slots to receive wheel axle, so trail is adjustable about the stock setup position. It is just a few mm aft of this position.

    Frame is sturdy enough to lock out the suspension of a fork, if it does not have an independent lockout mechanism. We considered the telescoping element you described, but went for a more universal geometry.

  8. CyclemotorEngineer says:

    Stokes,

    Thank you for your questions.

    I used the Dewalt packs because they are the best. They can be discharged fully and recharged in only an hour. This can be done at least 2000 times, which translates to 30,000 miles on this bicycle. They will not catch file or explode. Internal cells are manufactured by A123 systems, and they sell developer packs which cost more than the Dewalt packs and do not include charger or battery monitoring system. It was much easier to design and build the discharge circuitry for the Dewalt packs than start from scratch with cells. For production, we will have to do something else, but the prototype shows what is possible with cutting edge (pun intended) technology from Dewalt and A123. If only they would give an OEM discount for this little plug!

    Regarding storing the Cyclemotor, I would not hesitate to lock it to a tree in most neighborhoods if it cost $1000 and had a built-in battery. Otherwise, it can be rolled away to the office, garage, or (heaven forbid!) car. A rack could hold it on the back, but may be unwieldy.

  9. amp2003 says:

    Thanks for the quick response. It’s always nice to get inside the engineer’s head.

    And just FYI A123 is also one of the developers for the Chevy Volt batteries. They know their stuff.

    http://www.freep.com/apps/pbcs.dll/article?AID=/20070810/BUSINESS01/708100367

  10. mastershake916 says:

    It’s interesting, especially as a purely bolt-on solution