Doug Burton
Zen MBB Master
Okay, here's some details. Probably this will slide into winter, but I will use it to develop the instructions for the Freerider Handlbar Kit when it's used with conversion kit components, which is why it's mocked up right now.
The motivation was to build something that could be taken apart and chucked into the trunk of even a really small car, or aircraft luggage-compatible. I also was looking into alternate frame sourcing for conversion kits, as this will accept wheels even up to 700c.
The frame source is this:
http://cgi.ebay.com/New-BIKEBOARD-Mini-Pink-Hibiscus-Scooter-Ages-7-10_W0QQitemZ310086943431QQcmdZViewItem?hash=item310086943431&_trkparms=39%3A2%7C66%3A2%7C65%3A15%7C240%3A1318&_trksid=p3286.c0.m14
I used the 16" wheel version because it placed the bottom tube about where I wanted it. This thing is MASSIVELY overbuilt because it's intended for kids to jump it off of stuff. Very thick tube walls; it could be lighter, but because the frame is small, it can't get but so heavy. I'll weigh it once I have more parts bolted on it.
First, photos:
The idea is to attach the fork with two through-bolts drilled 90 degrees to each other, through the really thick frame tube, perhaps with a reinforcer inside the fork steer tube. A plastic sleeve will be needed to match diameters, and will insure the fork will slide back out.
The seat attachement in the rear is mocked-up with a handy piece of aluminum round stock, but a classic flute-tube arrangement would work fine. The rotational load on the seat is taken up at the front attachment.
The front attachement is crude - a muffler clamp attached to a gate hinge. The hinge gets cut where the ruler is and drilled for the muffler clamp threaded ends. The long half of the hinge gets gently bent to match the curvature of the seat bottom.
Yes, Mark, I have a 60-t chainring and a 155mm Dotek crank for it. The ring needs to be pinned if I decide to use a front derailleur.
There is one subtlety here. The front seat attachment occurs at the downtube, and not the bottom tube. This causes the force placed on the rear fork attachment to be in tension, instead of placing a bending load on the fork steerer. This should also provide some passive suspension due to the tension load trying to "unbend" the fork tines. I am not convinced that a Cruzbike kit seat can work in this without some development - that would be the winter part of this. I also may be being a little conservative.
The nice Novosport seat and the drilling of same is part of my hesitation to build this bike.
The motivation was to build something that could be taken apart and chucked into the trunk of even a really small car, or aircraft luggage-compatible. I also was looking into alternate frame sourcing for conversion kits, as this will accept wheels even up to 700c.
The frame source is this:
http://cgi.ebay.com/New-BIKEBOARD-Mini-Pink-Hibiscus-Scooter-Ages-7-10_W0QQitemZ310086943431QQcmdZViewItem?hash=item310086943431&_trkparms=39%3A2%7C66%3A2%7C65%3A15%7C240%3A1318&_trksid=p3286.c0.m14
I used the 16" wheel version because it placed the bottom tube about where I wanted it. This thing is MASSIVELY overbuilt because it's intended for kids to jump it off of stuff. Very thick tube walls; it could be lighter, but because the frame is small, it can't get but so heavy. I'll weigh it once I have more parts bolted on it.
First, photos:
The idea is to attach the fork with two through-bolts drilled 90 degrees to each other, through the really thick frame tube, perhaps with a reinforcer inside the fork steer tube. A plastic sleeve will be needed to match diameters, and will insure the fork will slide back out.
The seat attachement in the rear is mocked-up with a handy piece of aluminum round stock, but a classic flute-tube arrangement would work fine. The rotational load on the seat is taken up at the front attachment.
The front attachement is crude - a muffler clamp attached to a gate hinge. The hinge gets cut where the ruler is and drilled for the muffler clamp threaded ends. The long half of the hinge gets gently bent to match the curvature of the seat bottom.
Yes, Mark, I have a 60-t chainring and a 155mm Dotek crank for it. The ring needs to be pinned if I decide to use a front derailleur.
There is one subtlety here. The front seat attachment occurs at the downtube, and not the bottom tube. This causes the force placed on the rear fork attachment to be in tension, instead of placing a bending load on the fork steerer. This should also provide some passive suspension due to the tension load trying to "unbend" the fork tines. I am not convinced that a Cruzbike kit seat can work in this without some development - that would be the winter part of this. I also may be being a little conservative.
The nice Novosport seat and the drilling of same is part of my hesitation to build this bike.
