BMX bikes are a unique frame geometry, essentially forgoing all travel efficiency for maneuverability and sturdiness. For how much abuse these bikes are designed to take, these are all good tradeoffs. But it turns out that these bikes also have an exceptionally low center of gravity, which could make them useful for drag racing, provided they’re given a suitably large electric motor and a few minor frame modifications.
The project began as a fun weekend project for friends [Sam Barker] and [Tom Stanton]. They had a 20″ BMX wheel with a massive integrated hub motor that seemed to be begging to be put onto a BMX bike that they had on hand. After hooking up a 72V, 20Ah battery to it they were quickly zipping around the driveway, but the short wheelbase on the bike was bottlenecking its maximum performace because the bike would wheelie under high throttle. To solve that, they broke out the welder and extended frame, which kept the wheelies to a minimum and allowed them to take it out and drag race.
Another benefit to the extended frame is that the bike has room to store its battery now as well; before the frame extension it was strapped to the side of the frame under the rider in a non-ergonomic fashion. The duo also had to figure out a braking solution since the BMX didn’t come with its own brakes, but a loaner caliper from a penny farthing was found for some basic stopping abilities. We might assume this bike is not street legal on many public roads, but not every ebike operates in the same legal jurisdictions you might be the most familiar with.
Really cool build but should’ve just dropped an extremely pissed-off two-stroke engine in at the end and had some actual fun
Don’t these people have jobs?
For some people, YouTube is their job. I’m not sure how much money they get with around 40K subscribers, but it might be enough.
They get most money from sponsors. Like racing drivers.
You don’t have hobbies? Some people program, or do home automation, or cycle, or build electric BMX “drag” bicycles.
“My name is Sam Barker, I ‘m a 33 year old captain currently flying the Boeing 737.”
I guess those people do have jobs.
hmm. the bike might have a low point of gravity, the rider has not and it weights a lot more than the bike.
the reason they made drag race bikes was because you could not put the engne in the front wheel for obvious reasons. with electric drive that is not a problem anymore and you don’t need a drag race frame. but yeah. youtube..
Weight transfer on launch means that putting the drive in the front wheel makes the vehicle slower though.
First of all amazing hack! But is anyone else thinking, “someone’s going to flip over the handlebars” with only a front brake?