That's another question on my mind. Thanks!One thing that you are going to want to do first is straighten up those dropouts a bit. The slots for the axle should be parallel. Yours have been bent open like a Y on that right side dropout. You also want your dropouts to be flat and aligned parallel with the centerline of the frame (when you are looking down on them).
There are several sizes for this type of adjuster bolt that fits your picture, 1/4, number 12. The adjusters people have shown above will fit, you may have to do a little file fitting but they work. Here are the same dropouts you have with rear adjusters.
Some of us seem to be hard on drive components! I have to run 3 piece bmx cranks and axle adjusters. I wear out chains stupid fast so I run KMC 410hd's.riding without them is a no from me, I kind of have a tendency to break cranksets though. the pisser is halfway through a ride when your tire starts rubbing on a chainstay. You really put a lot tension on the chain riding up hill and it pulls your hub out of square. i actually prefer the ones with wingnuts so I can cinch up chain stretch easily
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