ChiquiCycle!

Hey avid readers!

Sorry for the long delay, as a quick life update: in the last couple months I have started grad school at MIT (its going amazing!) and i joined the Electric Vehicle Team after my ex-roomie Victober infected me with the Electric Vehicle Fever. At the start of the school year, Victor and I worked on TinyCycle, after we finished it Victor and I took RailScooter and TinyCycle to the NYC Maker Faire, it was a day full of annoying delays (oversleeping, subway breaking down, forgetting to charge EVs etc etc) however it was a lot of fun and all the MIT folks raced their EVs around the power series track (Vicky and I also raced our EVs in the streets of Manhattan (not recommended) but that is another story...).

This whole experience left me really wanting a tiny electric motorcycle, just like TinyCycle. I looked around on craigslist and emailed/called/texted a couple of folks but never got an answer. Luckily for me  it turned out that one student group in 2.009 (MIT's Product Design Class) had taken apart a mini razor motorcycle as part of a class project and now it was sitting there alone in pieces. So i decided to do what every good samaritan would do... TAKE IT and give it a new home!. Thus my ChiquiCycle adventure started!

ChiquiCycle in Pieces

ChiquiCycle put together (no drive train or electronics)

It took me about a workday to put together all the parts I got from the 2.009 kids, it turns out they had lost the handlebars, the steering axle and most of the hardware. I eventually grabbed some scooter handlebars from MITERS, turned new steering axle pieces myself and grabbed some metric hardware from the shop. The motorcycle was now ready for its electronics! I started by procuring all the important parts: Motor, Controller and batteries. I had my ex-roomie victor help me with the battery pack (please see his excellent tutorial on how to assemble a Li battery pack!). The motor I used was this one and I decided to use a sketchy brushless motor controller from China that victor had laying around (in the near future Victober and I are planning to write a paper on sizing your motor and controller for your pocket bicycle).

We aimed to make the drive train assembly as simple as possible. I used an aluminum L-bracket to mount the motor. We took the driving sprocket out of the old motor the motorcycle came with. These sprockets normally come with a D shaped hole so it can transmit torque. I was lucky that the size of the sprocket bore was an M8 (same as my motor) this saved me the time it would take to machine an adapter. I pressed a spacer on the shaft then sanded the shaft to give it a D profile, put the sprocket on the shaft and finally machined a collar to constrain the sprocket axially.

my drive-train assembly

close up of driving sprocket mounting

The controller mounting was pretty easy (i just reused the mounting holes for the original brushless controller.

ChiquiCycle Frame with batteries, motor and controller! ALMOST DONE!

At this point ChiquiCycle was ready to roll!

We did some test runs (videos pending...) and it was obvious that we needed the controller to output more current to make our ride more exciting! With the help of Charles we hacked the motor controller to output more current and added hall effect sensors for motor startup. The scooter handlebars were making it impossible to ride chiquicycle semi-comfortably so I changed them to bicycle handle bars. I added a couple more pieces of the original plastic body and a Tesla decal and this was the "final" product:

ENTER CHIQUICYLE! (videos will be posted soon)

fun fact: I posted the above picture to the Tesla facebook page hoping that it would give me the opportunity to work at Tesla in the near future! I got over 130 "likes" from random people! My hope is that Elon Musk sees it and offers me a job in Tesla!

I'd like to thank the people that helped me out with this project, namely Victor, Charles, Lauren, Rango and Harry!

my awesome pit crew! (lauren and rango)

This project along with Victober's TinyCycle has pushed several friends to buy a tiny motorcycle! We are in the process of creating the Pocket Motorcycle Squad (PMS) and we aim to have a techfair booth in early 2013. Here's a picture of Lauren's chopper and future member of PMS!

UPDATE: Here is an instructable for Chiquicycle! It has almost 30k views and it won 2nd place in a "cars and motorcycles" contest winning me a bottle of "water spot remover"