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Mar 26, 2012
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Maplewood, MN
Welcome aboard the RRB forum train! These build offs are extremely fun and you will expand your horizons in the realm of bike building.

"A couple of Roadmaster frames..." Hmmm...

The first thought that comes to my mind is a "Push me - Pull you" type of design with two front ends?!? :bigsmile:

RaT oN~!
 
Aug 14, 2019
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Curious where the BB will be located and wondering whose bike will be longer...

Carl.
It's going to be longer than this, I plan to rake the headtube and swap out these 20"forks for 24's.

The red dots are where I plan to mount the BB and the jackshaft idler sprockets. The BB location will probably be a little lower than the dot.

P9260522_LI.jpg


This is where I could use some help. Does sprocket size matter when running a jackshaft? I've only seen larger sprockets being used.
 
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Aug 14, 2019
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A lot depends on your jackshaft gears.
You can 1 to 1 the gears on the jackshaft and make it easy to figure, or step up for speed or step down to easy the pedaling... (I think that's right)

Carl.
I would do 1:1 for a start.

I found some sprockets/locknuts that appear to fit a freewheel hub. As these seem to be much narrower than a single speed freewheel, I was hoping maybe I could fit them on a freewheel trike adapter. The smallest I found are 14t, if size doesn't matter, I would use them.
 
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Aug 14, 2019
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Bunch of old Geezers!!!!!!!!!!!!!:rofl:

While I wait for the new rear spring, sprockets, and the freewheel adapter to show up, I thought I would work on losing the big horseshoe that is attached to the fork.

I used a piece from a rusty bent up sissybar for a brace/brake mount. After it was welded up, I cut the old brace brake/mount off.

Before

P9260525.JPG


After
(I still need to make a tab for the brake to mount to.)

PA040534.jpg
 
Last edited:
Aug 14, 2019
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One step forward, one step back.

Forward,
The rear spring arrived today. I welded the spring mount and then made the brace for the bottom tube of the frame. Then I tacked the BB in place, I think with a shorter crankset, it will work.

PA050536.jpg


Backward,
The new brace for the forks is not working out. With the wheel mounted the forks bind and there is no suspension. I assumed that when my weld cooled things might have moved, so I made a cut through one end and it immediately had a gap. To keep things centered, I cut through the other side, centered the piece and welded it back up.

It still binds!:mad:

Back to the drawing board.