Re: Anyone built up a Skyhawk aluminum frame with internal tank?
If you look at the photos on the jakebike site you will see that there IS a hole where caliper brakes could be mounted. This frame is based off the GT-2 frame (which is steel, not aluminum) and the GT2 also has a hole in the crossbrace for the seat stays. I used mine for mounting a fender.
As for 700c wheels? I don't know if they'd fit. I've never considered it for my GT-2 bike because, frankly, narrow wheels on these bikes just seems like a bad idea to me. I built one narrow wheeled motorbike and it wasn't very long before I removed the motor for another project. WAY too much vibration to be comfortable for me. Fat tires soften the ride.