Gravel Grinder Green Motobike 1930

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MazdaFlyer

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Picked up this old Schwinn Motobike frame at a swap meet. It’s had a rough life as evidenced by the bumps and bruises under the blue paint.
It came with a fork sans the truss rods. I had some other parts for it so I began some mock-up work for the $10 frame.
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I ran a survey for determination of a base color. The results so far are either for green or black.
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I had a 700c wheel set so I sourced some on sale 700x38c gravel tires. Gravel Racer Klunker, maybe that’s a better title.
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I posted a question about the fork it the “How To” forum. I have two forks, both have holes in the blade ends. I’m thinking of turning the holes into slots in order to get 3/8” axles in place. The truss rods would maintain their holes. I might also use the safety clips that come with new wheels.
Has anyone had experience doing this modification?
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I posted a question about the fork it the “How To” forum. I have two forks, both have holes in the blade ends. I’m thinking of turning the holes into slots in order to get 3/8” axles in place. The truss rods would maintain their holes. I might also use the safety clips that come with new wheels.
Has anyone had experience doing this modification?

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If you have a hand grinder, they've got thin steel cutting discs that make the modification you're talking about easy. I'd drill the holes to the desired size first and slot them straight thru afterwards. I think that's the best way to keep the axles centered...

Carl.
 
If you have a hand grinder, they've got thin steel cutting discs that make the modification you're talking about easy. I'd drill the holes to the desired size first and slot them straight thru afterwards. I think that's the best way to keep the axles centered...

Carl.
Thanks Carl. Thats what I had in mind. I was curious to know if anyone had experience doing it and wondering if they had safe riding after.
The fork ends are pressed steel not forged.
 
I've been thinking about gravel grinders lately too, but I'm looking at it from a MTB point of view. Are you doing drop bars? All my life, I've been opposed to them, but the new gravel ones are wider, and have less drop.View attachment 105408 View attachment 105409
Not that fancy, maybe flipped over tourist/touring bars. I have a newer Raleigh Preston with flipped bars. I find it has a really comfortable riding position.
 
Cool. Nice rear dropouts.

Been thinkin about putting an 8-speed 700c wheelset on a 63 Schwinn Corvette cantilever frame.

I can force fit the 700x35's in the back. But if I want to go with larger tires, will need to remove the fender mount tab and grind a little off the bottom of the dropouts.
 
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Yeah, the new bars ain't cheep! I was thinking about experimenting... Try to cold set an old road bike bar from the stash. Seems unlikely that I'd get both sides to bend evenly.
 
Yeah, the new bars ain't cheep! I was thinking about experimenting... Try to cold set an old road bike bar from the stash. Seems unlikely that I'd get both sides to bend evenly.
The Preston...
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DO a low ratio so when you climb up loose gravel hills, you can grind them down real hard and spin out.
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And use grips and bars like these. I want this bike.
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I nave an modern, steel gravel grinder that I will post soon. That bike has been a lot of places and done a lot of things over this past year.
 
DO a low ratio so when you climb up loose gravel hills, you can grind them down real hard and spin out.
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And use grips and bars like these. I want this bike.
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I nave an modern, steel gravel grinder that I will post soon. That bike has been a lot of places and done a lot of things over this past year.
I plan to experiment with some different gear ratios as mine will be a SS. I have several sizes of rear cogs for starters.


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I set out today to experiment with my old 28” truss rod forks this morning. I planned to turn the blade holes into slots capable of running 3/8” or 10mm axles. So first I drilled out the existing holes. I started with the blue fork as the potential sacrificial lamb. I used a small drill press, vise and clamps.
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After success with the holes I moved onto the slots. I had a cut off grinder but decided I might have more control with a Dremel tool.
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After getting the slots done I located a drill point for the “lawyer washers”, and drilled away.
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So after completing this blue fork I moved onto the rusty chrome fork that I had previously mocked up. It was successful also so I spent some time mocking it back up with the wheel in place.


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It was a little tricky getting the fork blade spread open to fit the modern 700c hub. I used an wood clamp as I’ve done before, the trick is to find the right height and spoke location.
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With the wheel in place I refit a different set of truss rods as the first pair were too short. Not sure if I’ll use the current stem or bars or not, they could change.
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At least it’s a roller...
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Now to contemplate a base color, I’ll strip the paint. I did a test strip on one area, bare metal under the blue. The blue comes off easily. The final paint may be determined by what I find under the rest of the blue.

I’m thinking this project is a way of unwinding from RRBBO#14...not sure I want to do another one.

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Going to try a different stem.
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We did some experimenting with paint. My wife picked a few of the colors. I like the metallic green but it needs to be darker. E1 and A1 look pretty good as to darker green.
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