DIY Jackshaft

Did you just drill through the frame? ?

I am in the starting stages of building my own frame, so something like that would be easily added.
 
Well, you need to find some tubing that you bearings fit into and drill a hole in the frame to accept that tube. Do your homework on gearing, I can't stress that enough! I'm running 22t off the input side and just ordered a 14t to go back to the rear cassette, which was a 16t. I spent about $60 with shipping and everything. Staton inc is a great resource for jackshaft parts, that's where I went. Feel free to PM me with any questions.
 
I agree. Jackshaft mounted freewheel is much less expensive and more reliable than crank sprocket freewheel.
I use a similar setup on my OCC 5 speed.
 
Here is a better picture of mine
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BarelyAWake said:
Not sure if sarcasm or not lol - but as it can look complex at a glance, it's just a 5/8" keyed shaft, two cogs & a "BMX" freewheel w/shaft adapter... it looks busy because this particular setup uses additional stop-collars rather then just set screws on the cogs (for spacing & to be sure the bearings stayed put) but more then anything else it's got a disemboweled & reversed rear derailleur arm for a pedal chain tensioner - given it's a multispeed recumbent, that pedal chain is something ridiculous like eight feet long or so (total).

Another difference is this isn't a pedal crank freewheeled setup - so some of the "complexity" is actually simpler, it's jus' all on the jackshaft rather then spread out all over the bike. This jackshaft/freewheel design is FAR less expensive then the specialized shift "kit" freewheel cranksets but more importantly, it's also significantly more reliable as the engine & pedal drives are isolated until the final. Also, unlike with the crank freewheel setups should that freewheel fail, you can still get home :)

Click to expand...

Maybe just a wee bit of sarcasm (due to the angle of the shot) but I can see clearly how it works and it really is rather simple. Others may see and think differently however. I am a simple kinda man, as Lynyrd Skynyrd put it :D
 
I used pillow block bearings. I found them for a good price on eBay for $15 for a pair.

I tried using U-bolts and they didn't work. They do not have enough gripping surface area to prevent the jackshaft from turning around on the seat tube. So I made my own. Very simple part, made both mounts in about 20 min from some scrap aluminum, using a manual mill and a bandsaw. You could probably make similar ones if you find a big enough drill and figure out how to hold it in a drill press. Each of my mounts grips 1.25" of the seat tube, for a total of 2.5" area, almost 360* around. It's not going anywhere.

If I had a welder, I would go with those two-piece shaft collars and just weld a plate directly to two of those. Would be much lighter.

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