complications and decisions, decisions, decisions....

[FurryOnTheInside]

It held up better than the shift kit did...

That was not a Shift Kit, though. You have the Chinese knockoff jackshaft kit that is only based on the old version of the Sick Bike Parts Shift Kit.
I know that was mentioned in earlier posts but it's inaccurate to use the name of the quality product in vain, and say a "shift kit" failed when it was the cheap Chinese knockoff. The guys at SBP worked hard to make the Shift Kit robust and reliable.

 

[GreenMantis]

I thought I was clear enough that I used the cheap, Chinese kit. But I'm glad I did, the problem I have with it will apply to any of them, the freewheel made it too damn hard to start the engine, at least compared to what it was. But it will donate some of it's parts to the tricycle I will do shortly. Those sprockets will come in handy...

 

[GreenMantis]

So I finally got the bored out sprocket that fits over my 3 speed hub. I put the old one piece crankset back in, but now the crank hits the muffler no matter how I adjust the engine. It's the same crank, and the same muffler that worked before. The only thing that's different is I put in new bearings and races, could that do it? Somehow I don't think so, but what could have changed? Somehow I doubt that those cranks are going to be easy to bend, so I am at a loss as to how to get around this.

 

[5-7HEAVEN]

This looks like it might actually work! The hole in the sprocket is the right size, or close enough, anyway. I have a 44T that's too big, and it's dished so that the teeth are offset, that won't work, and a 36T that's too small, so I'm thinking that a 40T would work best. But even if I can't use the caliper, and have to use a rim brake, it's still a solution to how to mount the sprocket on a rim with a brake disc. Maybe I should make another thread and follow it's progress. This, imo, is better than the sprocket and rubber thingies on the spokes, or even the adapter that mounts onto the hub. First, I think I'll get a 40T sprocket, drill the new holes in it, and polish it up on my belt sander. The sprocket is thicker than the brake disc, but will still fit into the caliper, with some adjustment of the pad spacing, it should be fine.

UPDATE: OHHH, LOOK WHAT I FOUND!
http://www.bikeberry.com/engine-kit-parts/drivetrain/40-tooth-rear-disc-brake-sprocket.html

It's outa stock, but it's something to use instead of the other options.

JMO, I'd have opted for the shift kit with a HD freewheel.
You were SO CLOSE! to installing it

HOWEVER, coaster brakes aren't meant to be used with shift kits, so you'd have had to fab rim brakes.

Exhaust pipe hitting the crank? There are several options:
1. Move the engine slightly.
2. Grind off the interference from the crank.
3. Use a torch and bend the pipe out of the way.
4. Use a different/wider bottom bracket.

Good luck.

 

[FurryOnTheInside]

Dent the muffler.

Elongate the holes in the muffler flange, allowing you to rotate it a little.

Or do a bit of both. Worked for me.

 

[CrazyDan]

Fill the exhaust header with sand to prevent a kink, then heat it up and bend it just a little tiny bit. Quickest fix out there to move the exhaust over.