Columbia/MTD 8" wheel conversion/Fork Fab

#1
I've had this Columbia frame I've been holding onto for about 8 years with the intensions of building because my buddy has one and they are great riders. I was always missing the fork lowers, and the tubes on the forks were worn thin anyways, so after having a set of unknown fork lowers on ebay without selling a couple times and missing a couple deals on MTD forks, we got the crazy idea of making them work together.

Basically had a machine shop machine a step into a couple sections of solid cold roll round stock in order for them to slip into forks, and the lowers t o slip over the machined parts. Seemed to work out well. Funny thing is that after I already invested in this project, I was in my shed and found out what the lowers fit - ARCO. I have a purple one in the shed with the same lowers.



Here's the special machined parts:



The tubes on the fork uppers were cut down slightly for clearance for fork travel, then the machined parts were welded in, and then a plug weld up top to keep the parts from rattling inside the upper fork tubes.



Here they are assembled and still needing some spring material welded to the fork uppers for the springs to push against:

 
#3
Been having one of my guys Alex (AexC on here) work on a few bikes since it's been really slow here.

Engine will be an almost new Tecumseh Power Sport 3.5 flathead that came on a bike I got from Striggy years ago. We will be using a used TAV unit that came on a junk motor I had on the shelf.



Setting up the bracketry to make the minicycle brakes work on this frame:



Getting ready to set up the front:

 
#5
Painting day: Duplicolor T148 Dark Blue in the truck and SUV line. Has some pretty good flake in it and just a little darker than the T401 Bahama blue I'm going to use on my rider Bonanza soon.





 
#6
Alex has been assembling since last week in between customer jobs. Still some bugs to work out and maybe a better seat sometime in the future since this was just something lying around that we threw on.

Mooneyes decal because my kid will love it:









 
#7
Kickstand is a bicycle unit modified to fit using a fabbed bracket mounted with existing holes (we forgot to weld one to the frame before painting). Large washer welded to stand because I'll be parking on dirt a lot where I live.

Footpegs were fabbed out of some sections of 1" tubing from a junk Bonanza frame. Used the same frame to make some for the Gilson project we are in the middle of too.





Front brake will be nice:



Haven't decided on shocks yet. These were lying around so we threw them on. Seems like they should be longer to get the seat up in the back a little:

 
#8
Got to ride it today and it does pretty good for being a small engine. It's still a little torquey on first take off when the TAV engages giving the impression of the front end coming up a little but doesn't really, I want this bike to be mellow so anybody can ride it. So far it seems like it will work out well that way. This one along with the 2 Gilsons we are doing with oversize wheels should make some good riders at my place with the river and orchards right there.
 
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