Rides great, won't shift

[moteurhead]

I used a right hand derailleur with a funky mount. Seems the geometry is out of whack due to the rearward mounting location. Is a left handed derailleur fairly common? Can I modify a righty? I haven't seen any during my parts gathering expeditions, are lefties more common over seas? Other than shifting issue she rides nice albeit awkward on a crowned road. I used the large chain rings from a crank for the final drive, placing the larger as the driven sprocket for some added mechanical advantage...thought this might have been excessive but pedaling from a stop is easy with hardly any more drag than a normal 10 speed. I think when I get the shifting squared away I'll add rear brakes. She could be a hairy ride at the speeds she's capable of!

http://i189.photobucket.com/albums/z230/j_sin_album/chopper/2.jpg

In this image the derailleur is hidden by the chain ring.

http://i189.photobucket.com/albums/z230/j_sin_album/chopper/3.jpg

The slack chain issue has been resolved since this photo was taken. I'd like to use a left handed derailleur mounted to the nut securing the jack shaft, or something creative...any ideas?

[TheKid]

From the pic, it looks like the chain is way too short for the derailler to work. In high gear, the derailler should be vertical. Here's a link for adjusting deraillers, which includes getting the correct chain length:

http://www.sheldonbrown.com/derailer-adjustment.html

[moteurhead]

That's a great site for reference. It's hard to see in these photos but my derailleur is mounted to a bolt welded about 4 in. behind the shaft center line. When the derailleur moves forward to take up slack while shifting to smaller sprockets (higher gear) the idler cage binds on the largest sprocket. I'm gonna try (as a result of that site) making a bracket to relocate the derailleur mount to 1 in. below the jack shaft. -that would be easier than finding a "lefty".

[TheKid]

Also make sure to use a derailler with a "B" adjusting screw. That allows the derailler to be adjusted closer or further from the rear cluster. Relocating the mounting bolt will probably help immensely.

[John Lewis]

From the pic, it looks like the chain is way too short for the derailler to work. In high gear, the derailler should be vertical. Here's a link for adjusting deraillers, which includes getting the correct chain length:

http://www.sheldonbrown.com/derailer-adjustment.html

The link to the video on Sheldon's site is broken. Here is where to find it.

John Lewis

http://bicycletutor.com/calculate-chain-length/

[moteurhead]

Finally got it working. The key was location. and the chain was too long. The important part was keeping 180 deg. of chain contact on the driven sprocket, chain was skipping in high gear (small sprocket) also due to the cassette being inverted the hi and lo adjustments are reversed. also had to weld nuts to back of cassette and through bolt it to the hub because reversing the direction provided an undesirable loosening of the hub. all the bearings and dog teeth were removed and sprocket welded to the hub. I just unbolt the hub and spin off the sprocket for axle bearing maintenance. the rear wheel carries the free wheel so pedals aren't driven. Another problem is the shape and angle of the teeth on the cassette, it doesn't work well when being driven. my future design will maintain proper orientation to the drive line, by moving the cone to the inside of the mid drive.

The next step is to make a mid drive that will allow either pedal power or electric assist while not pedaling the motor or driving the pedals with the motor. The motor I have in mind (pros and cons of brushless verses cheap) is a long shaft Ford starter circa 1964ish part number 3115, still available at your local auto parts store for around $45. a dry cell battery from a "booster pac" will provide the power. The pac is designed to charge on a 110 ac outlet so all the circuitry is there to use. all of this will be hidden in a mock-up coffin tank, except the motor, it will be in front of the rear wheel under the mid-drive. The motor is way over powered and will consume massive amounts of energy but that's the nature of this beast, and it wont use one lousy drop of gas.