bici_mania

The overlap of me turning my own wrenches and owning geared bikes with horizontal dropouts as opposed to vertical dropouts is small so please forgive me if this question is dumb.

What is the ideal position of the axle in relation to the derailleur on a bike with horizontal dropouts?

I originally positioned the axle forward of the the derailleur hanger nut because it seems most horizontal dropouts are positioned that way.

When trying to solve a derailleur shifting issue I made a very tiny adjustment to the left adjustment screw because the wheel was not centered between the seat stays. After doing that I began hearing a rubbing sound when riding it. It took a bit to find the source but I found that the loop in the tension spring for the rear brake was making contact the slightest contact with the tire on one side.

I resolved this by adjusting both axle screws to move the wheel further back in the dropout. The adjustment put the axle behind the derailleur hanger bolt. Will this be an issue? Why not slide the wheel back all way back in the dropout?

rootboy 

Because the further back you move the axle relative to the derailleur, the more space, usually, develops between the upper jockey wheel and the small cog. The closer the small cog is to the upper derailleur pulley wheel, the better the shifting performance. In general. It also affects handling a bit and, if you have a very large big cog moving the wheel back in the drops can help the derailleur cage clear the big cog. So it's a tradeoff of sorts. Middle of the dropout is a good place to start , then you can tweak to and fro from there. My 2 centimes.

eschlwc

^ that's about the best advice you're gonna get. there have been a few of these threads, and there's not really any hard rule concerning axle placement in the dropouts unless you're experiencing shifting issues. sometimes a derailleur can reach its biggest cog easier when the axle is furthest rearward.

i always put mine square in the middle of the drop if given the choice.

those screws are usually called 'frame adjustment screws,' even though your title seems more appropriate.