Touring - Change from 74BCD to 58BCD

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View Full Version : Change from 74BCD to 58BCD

Booger1
09-21-08, 09:44 PM
I wanted some lower gears for my old legs,but really wanted to keep my old crank.So I looked into the quad ring adapter thing that takes Suntour? Regina? freewheel gears.Good idea,too hard to get gears for.So I figured,whoever made that thing is human,so am I,so I can make one too!

Got a piece of 1/8"-6061 tempered aluminum from work and brought it home.I wanted to see if I could make this with hand tools,things us types might have around the garage.I used a power drill,drills,coping saw,hacksaw and some hand files.

I used the above tools to make one of these out of aluminum:

http://http://i538.photobucket.com/albums/ff346/Booger1957/IMG_0178.jpg







Bolted it to the crank,set up the spacing,Done. Works Great! Shifts Great! How bout that...a 20 tooth gear on a crank with a 74BCD!

http://http://i538.photobucket.com/albums/ff346/Booger1957/IMG_0175.jpg

http://http://i538.photobucket.com/albums/ff346/Booger1957/IMG_0171.jpg

http://http://i538.photobucket.com/albums/ff346/Booger1957/IMG_0176.jpg

mjww
09-22-08, 09:17 PM
Brilliant idea. Doing the drawing using a CAD program, you can do any adapter you want with great accuracy, even add a 4th chainwheel. Gotta try this out! :thumb: