Multi Speed Chain Drive

K

kerf

Guest
As some of you already know, I'm a little unstable when off my medication, this may prove to be no exception. I have a Staton chain drive, left side output, currently setup as a two speed, works fine. What I've thought about may be a little far fetched and I would like input, negative or positive. Goes like this:

Step 1.
Convert gear box to inside drive.

Step 2.
Remove pedal crank and install backward, putting chain ring on left side, driving left hand freewheel on Staton hub. This results in a one speed, which is all I ever use anyway. Also pedal threads will be back wards, don't know if that will be a issue or not.

Step 3.
Rotate dérailleur as far forward as possible to place idlers in a more horizontal position.

Step 4.
Run chain from inside drive sprocket to right side 7 speed freewheel. I figure at least a 4 speed maybe 5 would be possible before chain alignment became an issue.

If chain routing to the dérailleur became an issue, maybe a wide ball bearing urethane roller could be employed to direct the chain. It should allow the chain to slide sideways for shifting.

I haven't been thinking about this very long, there has to be some impediment I've overlooked. What say you.
 
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Sounds doable Kerf, if the left side crank reversal became a problem with pedals loosening you could always use a crank off a tandem.

One thing I'm missing and maybe it's implied but this would mean reversing the engine and gearbox as well correct, driving off the right side?
 
Sounds doable Kerf, if the left side crank reversal became a problem with pedals loosening you could always use a crank off a tandem.

One thing I'm missing and maybe it's implied but this would mean reversing the engine and gearbox as well correct, driving off the right side?

The Staton box comes in two versions, outside (left) drive and inside (right) drive. I have the outside drive but it can be converted by drilling the right side of the case through the output shaft bearing and reversing the shaft. Someone, I can't remember who, had that idea and called David Staton, as I recall, he said it would work.
 
Inside drive:
http://www.staton-inc.com/image_thu...n-inc\images\Montague Final 009.jpg&width=800

Outside drive:
http://www.staton-inc.com/image_thu...aton-inc\images\5 3183 HPIM0611.JPG&width=800

What I'm getting at is both the above have the drive chain on the left side of the wheel.
Am I understanding correctly, your idea is to have the engine chain drive the cogs on the right side?

Both of those photos show the drive on the left hand freewheel, I would be like the Nu Vinci, except I would be driving the dérailleur freewheel.

http://www.staton-inc.com/Details.asp?ProductID=3249
 
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kerf,

you might want to look into putting some kind of chain guide half way between the BB and the derailleur.

this will triangulate the lower chain run keeping the chain approach into the derailleur flat and keep the derailleur from being drawn up into the bottom of the cassette.

if you have a standard 3 piece crank i don't see why you can't just flip it to the left side. you shouldn't even need a freewheel at either end on the left because the cassette freewheel will see the pedal force from that side as a coast condition.

how do you seal up the former left shaft opening ?

steve
 
In principle it could work if deraileur can be made to behave,lack of sufficient chainwrap. might be a problem.Some practical issues,need freewheel sprocket on gearbox for 3/32? " chain,max. cassette cog 32/34T I think,what overall ratios could be feasible?,
 
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kerf,

you might want to look into putting some kind of chain guide half way between the BB and the derailleur.

this will triangulate the lower chain run keeping the chain approach into the derailleur flat and keep the derailleur from being drawn up into the bottom of the cassette.

if you have a standard 3 piece crank i don't see why you can't just flip it to the left side. you shouldn't even need a freewheel at either end on the left because the cassette freewheel will see the pedal force from that side as a coast condition.

how do you seal up the former left shaft opening ?

steve

1/16" rubber bonded over the opening is what I'm thinking.
 
In principle it could work if deraileur can be made to behave.Some practical issues,need freewheel sprocket on gearbox for 3/32? " chain,max. cassette cog 32/34T I think,what overall ratios could be feasible?,

If memory serves me, never has before but if it does, I've got a 13-15-17-19-21-24-34 freewheel. Using the three largest freewheel sprockets with a 21 tooth on the output it should be 30.36/1 21.43/1 18.75/1 16.96/1. I'm currently running 18.75/1 & 23.08/1.
 
The one fly in the ointment, as far as I can see, is the chain geometry around the dérailleur. I don't want to tear apart my bike only to find an insurmountable issue. I need some type of test bed so I can try this idea in a low risk environment. Maybe a trip to the thrift store could provide me with a bike to test on.
 
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