kfong
100 kW
I’ve been working on this for a while now, but waited till I had something to show. I’ve wanted to do an RC build for a long time, but the noise turned me off. I eventually gave in because of the power level and what I plan to do with the bike. My local park has put in a small BMX track with some good size jumps. This would be a riot with a bike powerful enough to accelerate into the jumps and balanced enough to make it fun. A mid drive setup was needed and to keep it light an RC motor would be the best call.
The bike is a Kona Cowan DJ frame that had a lot of BMX parts on it. It's really built to take a beating. I wasn’t sure how easy it was to modify the bike but it turned out that bike parts are fairly interchangeable.
I was able to remove the Oddessy Spanish bottom bracket and replace it with a conventional Isis bracket. This allowed me to use a Cyclone crank with a freewheel I had built earlier with this bike
http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=11542
I decided to gut the parts from. If anyone has a spare cyclone crank arm. I’m looking for a set to get that bike together again.
Here is a picture of the Kona,
The cranks setup installed. You can see the I have clearance if I go with the 44t. Most likely I will try to find a middle ground since I plan to leave it as a single speed setup and don't really plan to pedal this bike except when needed.
The motor I will be using and the Nuegart 8:1 gearbox
I have to redo the mounts because it’s setup currently for the left side. I decided to go through the cranks instead so I would not have to deal with chain growth. I will be cutting down the motor shaft but will wait till I see what type of cooling fan I will be using.
View attachment 1
The batteries will be A123's. This bike will be used mostly for messing around a BMX track. I want to keep it as light as possible, but putting Lipos on such a bike would be quickly damaged during a fall. The batteries will be mounted in the triangle where they will have some protection. This worked well with my BMC Motobecane setup. I will have the motor mounted under the bike but high enough so it won't get in the way. I'm hoping to get it all done by spring.
The bike is a Kona Cowan DJ frame that had a lot of BMX parts on it. It's really built to take a beating. I wasn’t sure how easy it was to modify the bike but it turned out that bike parts are fairly interchangeable.
I was able to remove the Oddessy Spanish bottom bracket and replace it with a conventional Isis bracket. This allowed me to use a Cyclone crank with a freewheel I had built earlier with this bike
http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=11542
I decided to gut the parts from. If anyone has a spare cyclone crank arm. I’m looking for a set to get that bike together again.
Here is a picture of the Kona,
The cranks setup installed. You can see the I have clearance if I go with the 44t. Most likely I will try to find a middle ground since I plan to leave it as a single speed setup and don't really plan to pedal this bike except when needed.
The motor I will be using and the Nuegart 8:1 gearbox
I have to redo the mounts because it’s setup currently for the left side. I decided to go through the cranks instead so I would not have to deal with chain growth. I will be cutting down the motor shaft but will wait till I see what type of cooling fan I will be using.
View attachment 1
The batteries will be A123's. This bike will be used mostly for messing around a BMX track. I want to keep it as light as possible, but putting Lipos on such a bike would be quickly damaged during a fall. The batteries will be mounted in the triangle where they will have some protection. This worked well with my BMC Motobecane setup. I will have the motor mounted under the bike but high enough so it won't get in the way. I'm hoping to get it all done by spring.