horizontal dropouts and geometry

[lanton]

I don't think I could really notice any differences in my limited fiddling with the placement of the rear wheel in longer horizontal dropouts, but I was just wondering if when these bikes are designed is there a center point in the dropout that is used for measuring, or is there a range? For example BB drop, ST, HT, trail. The wheel base definitely changes, but is the vertical change considered too small to be noticed or measured?

[Andreu]

HIi Lanton,
it is an odd one this...in my limited experience there is a slight difference between wheels and it seems to change ever so slightly over about two years with the same wheel (out of true)....iMy guess is you only need a slight change in wheel set up or frame to cause a difference on the centring!
A:mad:

[Andreu]

Just reread your note and my reply doesnt really answer the question. Hope someone else can help you!
:confused:

[lanton]

thanks anyway, what I meant was only looking at it from a side view, 2 dimensional way, where moving the wheel back and up or forward and down might change certain measurements slightly. Must be very small, but just wondering if there is a standard reference placement in the design phase.