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My plan for the fork so far. I'm going to cut the legs off the main fork about 5 inches below the crown. Then crimp the last couple inches and drill 1/4" holes. The I'll take the donor fork and cut it so I'll have 2 legs 12 inches long. Then crimp the 2 ends and drill 2 holes the same to connect to the main fork. Then I'll make up 2 supports to go from the axle to a bracket on top of the fork. Like truss rods only stronger. If that doesn't seem stable, I'll have the fork welded instead of bolted together. I have the wheel positioned exactly where it needs to be.
Excuse the crude graphics, it's a wonder I can draw anything on the computer.

Forkmod1 - Copy.jpg
 
I'm holding off cutting the forks up so I don't wind up with a bunch of pieces I can't use. I'll give it a day or two to simmer before I get out the saw. I measured to see how large a wheel would work if I used a fork as is, just trimmed it down. It would be 10" at the largest but would track well, like a store bought scooter. I don't think they make a heavy duty 10" wheel., it would probably be a 8" wheel. That's a last resort though, I want the wheels to match and 20" is the smallest I want to go.

small.jpg


I thought I had lost the matching red adonized hub, but it was on an extra 26" wheel, so I'm going to re-lace it so I'll have matching hubs.
red hubs.jpg


And this work is done in the AC in my office, that's a big plus.
relace hubs.jpg


An advantage of the recessed rims is that the spokes don't need to be an exact size, the spokes can stick out past the nipples and not touch the inner tube. Even if the two hubs are different sizes, I can still use the same spokes unless they are too short.
 
The wheels are ready. Less than 2 bucks, 80 pesos for truing. 100% tip and still under 5 bucks.
I use 36 hole rims and the 3 cross spoke pattern to have a strong wheel. Any smaller and 28 hole is the max I can go. This scoot should have a pretty high weight limit.
wheels.jpg


I use the 7 speed cluster so I can see what cog works best when I try out the pedal system. The coaster hub had some slop, but the cluster grabs as soon as the chain is pulled. I'll need that for the ratcheting action. Maybe a motorbike brake pedal would work. It's still in the planning stage.

1651989466104.png
 
I laid out the forks and made sure I had them measured correctly.

forkmod3.jpg


Then I made the cuts. No problem.
forkmod2.jpg


I'm going to flatten the ends somehow so they look good, not hammered wildly.
I checked the fit again and found the original forks were long enough. I didn't have to chop up the second set of forks. :crazy:I'll find some use for those parts. I just have to remove the brake bosses and drill some holes. Then the supports and bracket.

fork mod1.jpg



I wonder if this may need to be a class two with the modified fork?
 
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@Wildcat , I just checked the Rules for the BO, and it looks like they have been modified to restrict the welding and cutting mods to the frame only. So as far as I can interpret, it looks like you are still okay in Class 1.
 
Good, no need to transfer everything over.

I have an idea for the drive figured out. I will use the bottom bracket on the frame and install a 3 piece square taper crank, with just non drive side crank arms on both sides, and both aligned together, not 180 from each other. So pedaling can be done from either side. There is enough clearance for the front wheel and the crank arm because the wheel is so far forward. Then a cable or rod running back to where the chain will attach along with a couple springs, and that's it. I'll post a pic tomorrow after I mock up the cranks, if I have 2 crank arms.
 
Still trying to catch up with your design work on this one. One option for a long board is try and locate an old wooden water ski. I used a water ski as a rear rack on Fugsley ages ago.
 
Your pump drive sounds similar to a system used on some Penny Farthings, a ratcheting treadle so the driver just pushed up and down. It's in the backlog of ideas I've been dreaming of building and perfect for a burrito styled build too. Imagine how low you could get without worrying about rotation.

Carl.
 
Still trying to catch up with your design work on this one. One option for a long board is try and locate an old wooden water ski. I used a water ski as a rear rack on Fugsley ages ago.
I'm limited by the 2 1/2" wide the two tubes on the bottom are. A water ski would work if it was wide enough. At 10" wide I may find it difficult to kick. I expect my skateboard deck will show up in a week or two.
 
Your pump drive sounds similar to a system used on some Penny Farthings, a ratcheting treadle so the driver just pushed up and down. It's in the backlog of ideas I've been dreaming of building and perfect for a burrito styled build too. Imagine how low you could get without worrying about rotation.

Carl.
That sounds about right. I gave it some more thought. It could go by pedaling downward or forward depending on the position of the drive rod. I think a pedal that pushes down will be easier to operate. Leaning my weight into it might be easier then pushing forward.

1652135297437.png
 
I had to update my visa in town so I stopped by their version of Harbor Freight to look around. We need new tiles for the house and a couple of other things. I picked up a big clamp and a set of vice grips to help with my build.

The clamp didn't work out as I thought it might, with a couple chunks of wood or with some metal to crimp the ends of the fork.
fork1.jpg


fork2.jpg


It's not made to do that. So, it was the old rubber mallet method to flatten the ends, flat enough to drill holes and bolt them together.

fork3.jpg


I figure that when I get it aligned with the struts at the right height, I'll tighten them down so they mash together. Then I'll clean up any edges with the dremel grinder.
 
I used a vise to flatten the ends of tubing. I found it harder than expected and I had to use a pipe over the vise lever which bent a bit too. My vise is quite bigger than the one you got, while being still clamped instead of bolted to the table, but I really had to sweat in order to manage.
 
I had some more free time, so I checked the frame alignment using the string method. It is off to the non-drive side a little. It might be made that way, nothing looks bent, but it was at the bottom of a heap of metal for some years.
string test.jpg


I swiped the crankset and cranks from an incomplete bike and added them to check the clearance. This also shows how I plan to make it work. The pedals will sit at that position when at rest and coasting. Pedaling forward will engage the drive rod and turn the rear wheel via a foot long (or so) piece of chain which is connected to a return spring. Pedaling can be done on either side. I will use the top chain wheel connection for the drive rod. The other 4 arms will get trimmed off. That's the plan.
cranks1.jpg


cranks2.jpg
 
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I used a vise to flatten the ends of tubing. I found it harder than expected and I had to use a pipe over the vise lever which bent a bit too. My vise is quite bigger than the one you got, while being still clamped instead of bolted to the table, but I really had to sweat in order to manage.
I broke the previous vise doing that. And my table is wood.
 
That bike, like the Worksman carts and those like that over here use a near vertical headtube. I'm wondering how mine with a slanted head tube will steer.
 
I put the fork together, but the fork needs to go to the machine shop for the ends to be flattened completely. I don't have the stuff to do it right. I think they have a press, but maybe just a big hammer.
You can see how far forward the front wheel is. The handlebars can go 3 inches higher by raising the stem. I have to make up 2 struts about 18 inches long to run from the front axles to the bracket at the top of the head tube. That still needs to be designed, I'll probably have that made up at the same shop. They did a good job on the flanges for Splat Rat.
locknuts.jpg

I also raised the height by a half inch. Recent research shows that kick bikes have a deck height of 3.5 to 4 inches. The Schwinn has a height of 6 inches and no one likes that on the reviews. So this will put my foot height at 3 inches, if I mount the board to the bottom of the two bottom tubes as planned. Another option is to mount it on top of those tubes. I would have to trim it a little. That might look better, showing the whole board surface.
One other consideration is the option to lower the fork legs to fit a 24 inch wheelset. it would need longer struts too. That would bring the geometry more into normal but make the board too high to kick. The chain drive would have to work great to consider that. Kicking would be the secondary drive mode then.

mockup 12 May 22.jpg
 

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