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Could you rotate the chain tensioner position so it pushes the top chain side downwards?
Is that really where you would want a tensioner? A chain can only pull, so the slack will be on the bottom of the chain. Plus if I don't need it, why have it?
 
Plan B.

The mount for the tensioner becomes the start of the mount for the chain guard. This is the front one, 1" x 1/8" steel drilled and bent. The back one is almost identical, but I won't mount it until I make the guard.

PA250613.jpg

The final mechanical piece to the shifter, a 1/8" locator pin to keep the cover in position.

PA250615.jpg

I'm really glad to be done with this shifter, it took entirely too long to rework.
 
The green chain is just for mock up.

I think I wasted money on that tensioner. While it is a pretty piece, if it's not needed, it's just clutter. The silver lining, I can use the bolt welded onto the frame for a chain guard mount.

You may still need the tensioner. With the suspension pivot between your chainwheel and the jack shaft the length of your chain line will change as the swing arm moves. It's not going to change by a lot but I would check out your chain slack at maximum suspension deflection before you discard the idler completely.
 
You may still need the tensioner. With the suspension pivot between your chainwheel and the jack shaft the length of your chain line will change as the swing arm moves. It's not going to change by a lot but I would check out your chain slack at maximum suspension deflection before you discard the idler completely.

That's a very good point.

I have a very limited amount of suspension, the amount of movement in the chain is very small. I don't think I'll have a problem.

SHIFTER UPDATE,

I hooked up a cable and ran it through the gears. It indexed each gear perfectly, both going up, and down.
 
As a beginner, I'm not sure if I'm wasting everyone's time posting this. You guys probably already have your tricks for doing projects like this.

My brake bosses arrived very quickly and I made a very simple jig to get them parallel. It's just a piece of steel thick enough not to bend with two holes large enough for the bosses to fit down to the adjustment plates with the 3 holes. After I drilled the holes, I elongated one slightly for some adjustment.

The first boss gets clamped to the bar, then the second one with the elongated hole gets aligned and clamped. I will be able to tack the first one in place, then fine tune the 2nd one before welding it all up.

PA270616.jpg

PA270617.jpg

It's supposed to rain all day, so I doubt I'll get to welding them until tomorrow.
 
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Don't accuse me of having tricks for doing things, mister! I am literally learning as I go. Rip a part apart, hopefully learning enough during the process to be able to get it back together again! Not so lucky with RockRat's shifters! Gained function in the ratcheting mech, lost 3 gears and the gear indicator!
 
Don't accuse me of having tricks for doing things, mister! I am literally learning as I go. Rip a part apart, hopefully learning enough during the process to be able to get it back together again! Not so lucky with RockRat's shifters! Gained function in the ratcheting mech, lost 3 gears and the gear indicator!
I'm learning as I go also, plus a little help from you guys. To be honest, I'm lost on a lot of terms and types of bikes discussed here. I guess if I make it here, I'll eventually catch on.

Good luck with your shifter.
 
It stopped raining and the sun is out. The rear brake is on and works great, it works well enough that I might not need a front brake.

After the brake was on, I looked at it and realized I had enough together to take it for a maiden voyage. With 1/2" pedals stuck in holes drilled for 9/16 pedals, two outer cables linked to reach the rear derailleur, no grease or adjustment to the BB, and a jackshaft adapter that is on backwards (which I thought for sure would unscrew itself in about 50 feet), I was out the driveway and down the street.

It is a little difficult to ride, the rake of the front wheel has it wanting to steer to either side, you have to hold on! I went through all the gears and got up to a decent speed for a few hundred feet. The small cranks are not as bad as I thought they would be. One thing that I am proud of so far, the drivetrain is nice and smooth. I think it will be a fun car show/fairground cruiser, I never planned on it being any more than that.

PA270618.jpg
PA270619.jpg

PA270620.jpg

PA270621.jpg
 
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I welded the cable stops back on to the rear suspension, then went over everything to tighten up for another ride. Both BBs were ridiculously loose and the front wheel was almost flat (never checked it yesterday).

I shortened these cranks and drilled, but never tapped them. To get the pedals to hold for a longer ride, I cut a 1/8" sliver of .040 sheet metal, bent a small 90 degree tab at the end to keep it from sliding into the hole, and tightened the pedals up. It worked great for a temporary hold, although a bit crooked. I don't really like this crank set, so if I ruin it, it's no big deal.

I got brave and decided to go around the block. The bike felt much better this ride.
Yesterdays short ride had me very nervous. I'm so worried that a weld will break, if the top tube weld fails, I'll be singing a few octaves higher. Today I was focused on noises and performance. There is a creak somewhere in the front BB crank area, it's not constant, nor does it sound critical. Maybe a little grease in there might help.:bigsmile:

This bike will be a lot of fun on flat ground, it certainly doesn't do inclines very well.
 
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COMIC NOOB ALERT!!!!!!!!!!

The noise I heard was the front BB loosening up again.

I've never owned a bike with a 3 piece crank, and the lack of experience has bit me in the hind end.
I completely forgot that I turned the front BB 180 degrees when I cut it off. I just concentrated on the flat spot is the bottom.

Now I have to cut it off and spin it around. I'm not real happy with myself right now. I just hope I can line it up as well as it is now.
 
It looks very cool. And the green chain ties quite well with the yellow fork.
Thank you. The green chain is just for mock up, and everything will be repainted.

The front BB has been cut off and swapped 180 degrees. It was a pain to cut off cleanly. It's tacked in place and has been tested. I'll finish welding it tomorrow.
 
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