49cc's on a Schwinn

I made a mount for my pedal chain tensioner tonight which was a remarkably easy thing to do using transfer punches. They cost something like $20 for a set which is money very well spent. Here's mine.

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The tensioner is designed to go over the back axle and hook into the the 3/8 slot in the dropout, but that ain't gonna work for me. I need to mount further up and onto the frame, but there's just the one 3/8 hole. What's gonna stop the arm from rotating on the mount?

So I decided to add a 1/8 dowel pin between the two pieces for positive location.

After taking the tensioner apart so I could work with just the fixed arm, I picked a spot with the most surrounding meat and drilled a 7/64 hole. Laid the arm up on the mount where I wanted it and using the 7/64 transfer punch made a mark on it.

Drilled the mount to 1/8" for clearance on the dowel. Reamed the 7/64 hole in the arm to .124" for a press fit on the dowel, and now they mate up real nice.

Next up was a knock thru the big hole with a 3/8 transfer punch to locate where to drill and tap on the mount ... and it was done.

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It's just hanging on with a magnet at the mo because I don't know where to put it yet! Waitin' on a longer #25 chain ....
 
Nice work FOG, I am chasing the same dog. Drive chain is now excellent but my Shadow Conspiracy Interlock v2 Chain Gold needs an idler. I worked on that when I got home from work. Not really work, I get paid to play with toolroom machines and make cool things. Transfer punches I have two sets like yours at where I get paid to play. But I am thinking of pulling the trigger on a USA made set for my home shop. The case hardened ones are not even very concentric. Good enough the imports but you get what you pay for.
Tom
 
Progress. I got my first chain done!! :) It's only the pedal chain but it's a start. 2 more to go ...

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Snaking the brake line thru is gonna be a bit tricky and it's also too short. If the caliper was on the left side and above the rotor where they normally go it'd be long enough. But it's not.

Anybody know what bleed kit might fit these Chinese calipers?
 
Beautiful FOG! I can't believe I never thought of using a derailleur idle sprocket on pedal side, that is slick.
I was a Schwinn mechanic in High School and still have a box of repair parts for my bicycles. Class A solution.
Tom
 
Six of my 7 bikes have pedal side tensioners and I love them. I took the pedal chain off the hybrid this afternoon to get it out of my way working on the hybrid took 5 seconds Lift chain off tensioner, then off pedal sprocket. No need to touch the rear axle. Always have correct tension. Use on both sides and it gets even better...I'm a fanatic on spring tensioners!

Why 6 out of 7? I've got a cool Schwinn chain guard I'll not sacrifice on my straight bar Excelsior Schwinn Autocycle build or it would be 7 for 7.



Rick C.
 
I'm still pecking away here. Since last heard from I've carved up a piece of 3/8 steel for a rear caliper mount and laced up the back rim. What's amazing to me is how complicated the bike of this bike got along the way! When I started this project I was naive enough to think a coaster brake would be just fine. We're way past that now.

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I spent an inordinate amount of time figuring out how to safely and sanely snake the hydraulic line thru it all. It needed to be well away from the tensioner, pass thru the pedal chain, and clear what will soon be a spinning back tire. I used 2 clamps in the back. One on the back of the tensioner mount and the other on a lug I welded on.

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From here I needed to go up the front downtube and I really didn't wanna weld some big ugly lugs on that. Zip ties would work but I'm entirely too old and fussy for something that easy. :) So I messed around with brazing a bit of metal on a tube that I could thread. Here's the experiment.

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That worked. What I actually did was drill undersize, braze, and then drill out and thru one wall of the tube with the correct size for an 8-32 tap. Here it is on the bike.

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I can live with that.
 
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I'm hoping to turn a block of aluminum into a jackshaft assy that can pivot to set tension on my primary chain. That's Plan A anyway.

The shaft needs to be offset for reasons that will become apparent later, but that presents an issue when ya wanna get that offset bore centered up in a lathe. So here's a bit of trickery I learned on the net that does the job.

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First I used the tables on my little mill to do the layout and a center drill to mark the spot, and then plugged that little pointer you can make yourself into the hole. The pointer is just a small pointed rod welded into a tube at the far end so it can wiggle around inside the tube with the mark. A center punch works too BTW. And then you adjust the jaws until the indicator don't wiggle no more.
 
I'm not exactly disciplined when it comes to workin' on my bike, so when I'm faced with massive interrupted nibbling on the lathe ... it takes awhile. But I've finally got one side of my jackshaft housing turned down.

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Avoiding chatter marks on that "interrupted" radius in the corner meant using some "tender" touching of the various knobs. Hardly necessary but it looks cool. I like it.

Time to turn it around ....
 
FOG said:
I'm not exactly disciplined when it comes to workin' on my bike, so when I'm faced with massive interrupted nibbling on the lathe ... it takes awhile. But I've finally got one side of my jackshaft housing turned down.

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Avoiding chatter marks on that "interrupted" radius in the corner meant using some "tender" touching of the various knobs. Hardly necessary but it looks cool. I like it.

Time to turn it around ....
Click to expand...

That's going to be a sweet Jack!

Rick C.
 
This is exactly the kind of thread I love to peruse. Craftsman with great skills and creative passions. More so perhaps because I don't have those skills. Woodworking perhaps but I don't even weld never mind do exquisite machine work. My hat's off to you FOG. Looking forward to further developments on your build. Fascinating!
 
Whizzerd said:
This is exactly the kind of thread I love to peruse. Craftsman with great skills and creative passions. More so perhaps because I don't have those skills. Woodworking perhaps but I don't even weld never mind do exquisite machine work. My hat's off to you FOG. Looking forward to further developments on your build. Fascinating!
Click to expand...

Whizz one of our old guys, Steve aka "fasteddy" is a master wood craftsman who developed his skills with metal to build amazing stuff on wheels. He's finishing up on an Indian Tri-car build with a beautiful chair upfront. Check it out on the forum "Motorized tandems & trikes" top of the stack, really long thread, you will be impressed. Also check out the threads in the "board track/ classics" forum many, many fine builds of vintage style bikes over there to inspire & instruct builders.

Rick C.
 
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