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I think that the problem might lie in the angle that that fork is working. When you add weight, the fork just jams itself instead of moving.
I agree, and even when they are free, they barely work due to the angle.

The problem I have is that even off the bike, with the fork vertical, it's bound up. I don't really know why it bothers me as they would basically need to hit a wall to function properly.
 
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I believe the horse shoe you cut off also keeps the fork centered and free as well as keeping the wheel square for brakes. It looks better now and you'd think your new bracket would've worked fine. But I'm thinking if you want a working suspension you're either going to need to reduce the angle or change your fork to a more mechanical design, like a Schwinn single spring or Monark dual spring style springer. Good thing is you've got plenty of time to sort it out. How's the clearance under the frame when you sit on the bike?

Carl.
 
I'm going to live without the front suspension working as I like the look of the forks. I don't think a springer would look good on this frame.

I have enough ground clearance with me on the bike if I put the jackshaft above the frame.

Now that I tacked the BB in place, I might try using the stock BB on the bottom frame for the jackshaft. This will possibly save work, and have a cleaner mount. If I do this, I will have to make a skidplate on the bottom of the frame to protect the sprockets, or possibly a bump stop on the front upright tube on the rear suspension to limit the travel.

I don't know much about bikes, so my explanations of what I'm doing might be a little hard to follow.


UPDATE

I cut the center of my brace (There was quite a gap!) and fit a plug into it that would hold it in place, but allow slight movement.

PA070538.jpg


While watching my cut, I pushed down on the fork to see if there was any movement. None. Then I took the wheel off to allow more flex and it felt the same. Put the wheel back on and tacked, tested, welded. It might not work correctly with my geometry, but at least it functions as it was intended.

I'm considering this a win.
 
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Sometimes when welding you get some swelling on the inside learned that on a seat tube couldn't get the seat bar in. Could be what you have going on with the suspension.

If you look where the brace is welded, the tube is larger for the plastic guides to fit, there is a gap between the tubes. But that is good information to know.

The forks work as good now as before the brace swap.
 
The freewheel adapter arrived today. When I put it up to the crank shaft, it fit over the end of the tapered square almost perfectly. It's just a bit too long for a nut to hold properly, but the flanged crank nut on backwards works for mock up purposes. I think it needs to have some taken off the back to get the sprockets to line up, so that should also solve the nut problem. I have another idea if that doesn't work.

PA080540.jpg


I really like the chain layout. I also found a more appropriate set of bars for a drag bike.

PA080539.jpg
 
The angle of the seatpost created a clearance problem between the seat and tire. If you look at the last pic I posted, the seat is really high. The solution was to cut and weld a bend in the seatpost. Now the seat sits nice and low, right where I want it.

I also cut and drilled the cranks. They are now 2" shorter. I have to get a set of taps to finish them up.

PA080542.jpg


PA080543.jpg
 
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I'm debating a chain guard. I like the mechanical look of the chain, but thought I would mock up a couple of guards and ponder the decisions.

The first design covers everything and gives a good area for some paint. I think this is too bulky.

PA090546.jpg




Next up is just cutting out for the sprockets. I like the front mag showing, but I would have to make something to dress up the back one as it's very plain.

Better, but still too bulky.

PA090550.jpg


Next was just the center cut out.

I really like this.

PA090548.jpg



Last is with the center and both sprockets cut out.

I think this is the winner.

PA090549.jpg
 
A short piece of handlebar with a 1/8" plate welded to it, and a hole. A shock bushing, bolt, and nut.

PA090554.jpg
 
Depending on if it's the same color as the frame, or an accent color in the finished product, I like a little more of the guard showing. Maybe just a window cut out of the chain line part, and a circle cut for the chain ring in front.

Plus if you leave a little more on there, you will have some good surface area for your Top Fool logo....:nerd:
 
When I came up with the idea for this bike I really only decided on two things, where I would cut and mate the frames, and that the stock shock mount would be a great mount for a shifter.

I was going to scratchbuild a shifter, when it dawned on me, why waste time and effort when I have the shifter that came on the bike to start out with. I cut the elbow off the grip shifter and ground out a hole in the main part of the body for the exit piece to fit in, then filled the cavity with JB Weld. I also cut the twist part down. The top left piece is a filler made from a PVC fitting.

PA100558.jpg


I drilled a small hole off to the side of the handlebar piece and mounted a roll pin in it. Then a matching but slightly larger hole in the frame mount to prevent it from spinning.

PA100559.jpg


The modified shifter body in place.

PA100560.jpg


Both parts to the shifter are tucked away for the night as the final coat of JB cures.

I also swapped the 650 spring for a 1500 on the rear suspension, what a difference! Well duh, it's twice as strong! The 650 had a very soft and bouncy feel, it was going to need a skid plate or bump stop. The 1500 has just a bit of movement when sitting and lightly bouncing on the bike. I don't know anything about suspension bikes, but I think a bit stiffer is better than too soft and bottoming out.

Now if my sprockets would show up, I could get my drivetrain ironed out.
 
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Modifying a grip shifter? Wow. I'm kind of confused about which part is now JB welded instead of being the manufactured bond? Maybe you can show us along the way how everything fits together.

My experience with Grip Shift (since 1988) is that it has to be very specific in it's configuration, or it doesn't work properly. If you've figured out a bypass to that, I'm really impressed!
 
Modifying a grip shifter? Wow. I'm kind of confused about which part is now JB welded instead of being the manufactured bond? Maybe you can show us along the way how everything fits together.

My experience with Grip Shift (since 1988) is that it has to be very specific in it's configuration, or it doesn't work properly. If you've figured out a bypass to that, I'm really impressed!

I'll try to gets some pics to explain what I did, it's very simple.

Could you explain what doesn't work properly, I don't know anything about these shifters. I do know that shifter was mated to the back wheel on the bike, so it made sense to me to use it.
 
I'll try to gets some pics to explain what I did, it's very simple.

Could you explain what doesn't work properly, I don't know anything about these shifters. I do know that shifter was mated to the back wheel on the bike, so it made sense to me to use it.
Just that the shifter itself is pretty finicky. Has to be mated just right for the cable pull and shifter indexing to work just right.
 
Just that the shifter itself is pretty finicky. Has to be mated just right for the cable pull and shifter indexing to work just right.

Looks like he just changed the cable routing/stop/adjusting screw from a 90 degree bend to straight ahead.

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