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View Full Version : Helping Handicapped Friend....Backwards Drive Train


andyinchville
09-11-06, 11:11 PM
HI All,

I have a friend who loves to ride but he was recently involved in an accident. While he can move aout reasonably well (after a long rehab peroid)....he is in such a state that he can ride a bike IF the front sprockets are on the opposite side where they are now (i.e. instead of the front chainsings being on the right side of the bike when seated they be switched to the left side when seated)...My question is twofold...on a cotterless crank system is it possible to put the front chain rings on the opposite side (by reversing the bottom bracket components) and secondly is it possible to use and internal geared hub on the opposite side by modifying it?...Also, can the
internal gear hub be welded up NOT to freewheel (my friend loves to ride fixed gear bikes) yet still shift? (has to be able to shift because since the accident he does not have near the strength he did before...needs gearing for hills)... I figured an internal geared hub setup would be easier to modify to be used on the opposite side in a fixed (non freewheeling) configuation than getting a welded up sprocket set to work with a deraileur mounted on the "wrong" side.
Thanks in advance for any and all help.
Andrew

kemmer
09-14-06, 09:31 AM
I can't understand what kind of injury would create this kind of need, but...

I don't see any reason why you shouldn't be albe to put the BB/cranks on the wrong side except that the pedals will come off. Put em on nice and tight with some thread locking compound and you should be ok there. I'm not sure about the rear hub. Fixed gear would probably be a mistake if your friend is recovering from an injury/lacks strenght.

frameteam2003
09-14-06, 08:15 PM
Talk to the BMX group ,some of their hubs are made to run a chain on the off side.

FishBykeSteve
08-23-08, 10:30 AM
I know this thread s old but someone may find use. for the info--In the early eighties there was a BMX bike with dual-sided drive(for extra stiff power transfer or something) that had to have had a left-side freewheel. Look in old BMX mags circa 1982 and you may find the make which is the start of your trail. Who knows, there may be a wharehouse full of them somewhere. A decade ago I bought 25 sturmey archer 5 sp hubs from the 1960s really cheap, and the distributor said they had hundreds of them so you never know...

dokydoky
08-24-08, 06:02 PM
This fellow managed to convert a normal freehub into a left hand drive one. Looks pretty difficult though.

http://www.recumbents.com/MARS/pages/proj/tetz/VFS/projtetzVFS02lefthanddrive.html


A left-hand drive BMX freewheel would definitely be easier, but it looks like you need a special hub too.

http://www.bikeparts.com/productinfo/ACS-SouthPaw-16t-Left-Hand-Drive-freewheel-18-60381-52095.html

FishBykeSteve
08-25-08, 08:14 AM
If this hub is expensive, you could take a regular hub and have any machine shop turn down and thread the left side on a lathe. It would probably be surprisingly inexpensive, especially if the chap is friendly and you explain the intended use.
The other possibility is to use an intermediate hub with double track cogs(both sides) as a jackshaft, mounted on a rear rack, then have the RH drive stuff (w/gears) run from the hub on the rack to the RH side of rear wheel. THIS MAY sound like a lot of fabrication, but if you get in touch with your local tallbike/mutantbike club they will likely be happy to do it on a volunteer basis. These folks are usually pretty civic-minded in that kind of way.
I'm glad the 3X I broke my ankle it was the left one!

Hobartlemagne
08-25-08, 08:36 AM
I think captain position tandem cranks operate the chainring on the left side.