Sleazy Rider

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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.
View attachment 193098

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.

View attachment 193097
That fork looks sick! 👍
 
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It might look good, but it didn't seem to be strong enough, and I see more alignment woes using the cut up fork ends. I have come up with another idea that should be stable and look good. :bigboss:

I think the pedal system will be the way I get around on this thing, so height is not a big issue anymore. The frame is made for a 27" skinny rear wheel, so a 26" fits with a 1.50 tire. Using a standard 20" fork for the front, a 20" wheel gives me about 7 inches of ground clearance. I may have to put a couple flanges on the fork, but it will be one piece and solid. No struts. For kicking it wouldn't be that easy, but not scraping the ground would be a plus. This also puts my handlebars at 43 inches. The black rim will match the front, and that's where I got the red hub for the 20" rear wheel. I could go back and relace them again, but I may get a sealed bearing set of hubs if they are still a decent price.
My longboard is still in shipping somewhere.

26 inch.jpg


This is nearly the same configuration the clone Easy Racer frame was made for. 27" rear, 20" front, with a long chain and an easy chair. But it uses a 26" or 27" fork with a 20" wheel.

1652428626532.png
 
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It might look good, but it didn't seem to be strong enough, and I see more alignment woes using the cut up fork ends. I have come up with another idea that should be stable and look good. :bigboss:

I think the pedal system will be the way I get around on this thing, so height is not a big issue anymore. The frame is made for a 27" skinny rear wheel, so a 26" fits with a 1.50 tire. Using a standard 20" fork for the front, a 20" wheel gives me about 7 inches of ground clearance. I may have to put a couple flanges on the fork, but it will be one piece and solid. No struts. For kicking it wouldn't be that easy, but not scraping the ground would be a plus. This also puts my handlebars at 43 inches. The black rim will match the front, and that's where I got the red hub for the 20" rear wheel. I could go back and relace them again, but I may get a sealed bearing set of hubs if they are still a decent price.
My longboard is still in shipping somewhere.

View attachment 193240

This is nearly the same configuration the clone Easy Racer frame was made for. 27" rear, 20" front, with a long chain and an easy chair. But it uses a 26" or 27" fork with a 20" wheel.

View attachment 193241
You could still give the 20" fork a slight kota-bend to get the complete setup a bit lower. I think it would be worth a try with a spare fork...
 
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It will have to sit level, so the front will need to be adjusted in height to match the rear 26" wheel. So a bend may be in order, or a flange bolted to the fork.
I ordered up a new 20" BMX fork, pedals, and sealed bearing hubs, in gold. The hubs were cheaper than before.
 
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As long as I'm modifying the fork, maybe I could add suspension somehow. I've got a few seat springs and a springer fork spring to use. Being higher off the ground, there could be some spring action without scraping.
I picked up some springs for the return on the drive system. These are for the brake pedal on a motorcycle. I may only need one, but I'll see how the tension is when it goes together.
I forgot I had this SRAM 2 speed automatic hub. It shifts to high gear at about 10-12 mph by itself, so it may work well if I get going that fast. I'll probably need a good downhill run to use high gear.
sram and springs.jpg


The caliper brake will reach the 26" rim after all.
caliper brake.jpg
 
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I had good luck with the fork on Splat Rat, and I think this one will work well also. This used two springs and doesn't move unless you really bump something or put all your weight on the fork. Good for offroad.
f10.jpg


My current plan is a simpler fork than that one. From the main fork, a couple of flanges to a u shaped strut that will go over the front wheel. Only one will be needed. The bottom of the spring will attach to the top of the U and the top to a bracket on the top of the fork tube. One spring only should give a cushy ride. The measurements have to wait until I get the 20" BMX fork and size it up.
 
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I ordered a 20" fork online, but still asked for one at the bike shop when I stopped to get the wheel trued. They had a bunch of them, but as I suspected, none would work for me. The head tube on the Scurf is 6", nothing they had came close. Then the owner went rummaging in the back and came out with this old 20" road bike style fork. The threads had some damage to boot, but I bought it anyway. it has a crown that almost matches the lugs on the frame, and they'll probably get painted red like the lugs. Black with red trim is what I have in mind. My ordered fork showed up when I got home. Same as the other BMX style, too short. But it went on the 20" heavy workhorse frame I got from the junk last month. They use those frames for sidecars and work carts over here. That's a project for later.

hd rp bike.jpg


mockup 16 May 22.jpg


Now with the rear wheel and fork in place, I can estimate how the front will sit. The lower tubes on the frame need to be 7" off the ground to be parallel to the ground. There's just a little adjustment in the rear dropouts, so the front will be modded to that height.

This shows the clearance of the cranks and my current idea for the front. I'll use the big spring from a chrome knockoff springer. You can tell I got an "A" in computer graphics class.
front layout 16 May 22 - Copy.jpg
 
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I tried the fork out just where it sits. The height difference front to back doesn't seem like a couple inches. 9" in front, 7" in rear. The board will sit about 1/2" below the frame.
I'm going with this configuration to see how it rides with the board at a slight incline. I still may make up a springer front, but this keeps it lighter and a better steerer. Transporting it to good places to ride is another consideration. With the wheels, it's 88" long, minus the wheels it's 66". I can put it at an angle on the bike carrier and take it anywhere. edit: with the wheels off.
While waiting on the board, (which is supposed to be here in town from last week) I'm going to start on the drivetrain.

mockup 17 May 22 - Copy.jpg
 
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Weight won't be the issue, the length will make it a bear to get up that stairwell. Even with the wheels off.

I spent some more time just looking at it. Even though it'll have a board on it for stand up foot or pedal power, if I added a seat like the recumbents have, it could be ridden sitting down, just pushing the two pedals, no full rotation of the cranks, but pumping both at the same time might be an easy way to get around. And the board would be a foot rest while coasting. But the seat would have to come back off to stand up and go. Unless I can figure a way to have a comfortable seat that isn't in the way or could fold out of the way.
 
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I got started on laying out the drive system. I had to take into account the crank arms contacting the front tire. Also had to limit the rearward movement of the cranks so the bar and chain will stay snug when at rest. I would also like to make a stop for the cranks going forward, so they can't touch the tire. With the height, I don't need to cut off the extra sprocket arms, I'm using the arm at 42" in the pic for the connection point.
drive4.jpg


drive2.jpg

The alignment of the chain over the cog must be perfect or the chain will jump off. So I lined up the spring attachment, but that might have a different connection point after the board goes on. I dug out a 16 tooth cog in case I need a higher gear, 18 should be fine though.
Drive1.jpg

The piece of chain I'm using will be shorter, but enough for 6 inches of travel across the cog. The cranks, as they are now, will provide 3 1/2" of travel with each push. It would be over 4 inches if they went further forward, but in a turn would contact the front tire. If I need more travel in the chain, I can attach it higher up on the crank arm, but the hole is already there in this setup.
I plan to use a length of 1" flat bar, aluminum or steel, about 40" long to connect the cranks to the chain. It will run from the cranks to the chain, close to the frame and have bends at each end for alignment. It will probably be 2mm thick.
drive3.jpg

It may need a guide to keep it in line, but the return spring may hold everything in line.
 

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I got started on laying out the drive system. I had to take into account the crank arms contacting the front tire. Also had to limit the rearward movement of the cranks so the bar and chain will stay snug when at rest. I would also like to make a stop for the cranks going forward, so they can't touch the tire. With the height, I don't need to cut off the extra sprocket arms, I'm using the arm at 42" in the pic for the connection point.
View attachment 193757

View attachment 193755
The alignment of the chain over the cog must be perfect or the chain will jump off. So I lined up the spring attachment, but that might have a different connection point after the board goes on. I dug out a 16 tooth cog in case I need a higher gear, 18 should be fine though.
View attachment 193754
The piece of chain I'm using will be shorter, but enough for 6 inches of travel across the cog. The cranks, as they are now, will provide 3 1/2" of travel with each push. It would be over 4 inches if they went further forward, but in a turn would contact the front tire. If I need more travel in the chain, I can attach it higher up on the crank arm, but the hole is already there in this setup.
I plan to use a length of 1" flat bar, aluminum or steel, about 40" long to connect the cranks to the chain. It will run from the cranks to the chain, close to the frame and have bends at each end for alignment. It will probably be 2mm thick.
View attachment 193756
It may need a guide to keep it in line, but the return spring may hold everything in line.
I couldn't wrap my head around the propulsion idea before but that makes it much more clear. I think I can see inside your mind now
 
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The front wheel didn't sit right, so I checked the fork, it's bent. I probably did that putting the wheel in, the fork is made for a narrow axle. So I used the graph looking cover on my bench to line it up and do some straightening. It's real close, that's good enough. It's easy to overdo it and wind up with junk. I have a bin full of that stuff.
1fork bent.jpg


1fork.jpg


Then I aligned the drops using the monkey wrench method.

1dropout.jpg


Then on to the drivetrain. I still had an 8' long piece of metal from when they made the trim for my stairway. It's thin, but should work because the pull is lengthwise, no twisting. I put a couple of bends to keep it as close to the frame as possible, so it won't interfere with kicking.

1layout 19 May 22.jpg


If I let the cranks come back farther than straight up, I'll have 4" of travel where the chain attaches in the rear. I think the chain will go right on using it's masterlink, after I round the ends.

1layout2.jpg
 
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