My bike has an aluminium frame and I measured 134mm rear dropout spacing. The wheel it came with has 130mm OLD. The dropouts are quite a bit flexible, the QR pulls them in on tightening. This is the wheel it came with as far as I remember. I am the first owner, but rear and front rims while looking very similar don't quite match. Cannot remember to have (had it) changed.
I am driving this bike for years and thousands of kilometers without breaking the dropout. After a recent need to replace the sprockets and discovering that even the 12-34 megarange freewheel is not available any more I decided to upgrade to freehubs and cassettes. Got a used 7-speed hyperglide wheel to match the measured 130mm OLD of my old wheel and transplanted a current 8/9 freehub onto it, staying at 130mm OLD. Conversion is done for some time and drive quite a bit with it, but there remains a nagging thought:
134mm is a weird spacing, isn't it? I checked with bolts, the dropouts are parallel, unclamped, and they still look parallel clamped to 130mm.
Could this be a 135mm frame, set to less dropout spacing by long use of a 130mm OLD wheel? And is 130mm OLD the way to go, here?
Before transplanting I tried putting in wider hub: pulling the dropouts slightly apart I was able to get it in. The 130mm hub is easier to get in and out and I have been using such for years and miles. On the other hand, 135mm is "closer" to 134mm and would allow for less dishing.