Ok so i was having a talk with someone about rear wheel spacing. I have a frame that has 126 rear spacing and i've put 130mm wheelsets in it. Should i have this frame cold set to 130 or just leave it the way it is. It's only 4mm difference which is 2mm on each side. I've been using the 130 wheel on the 126 mm drop outs with no issue. sure it's just a little tight when i put it in but other than that i've had no issues.

can anybody provide some advice or info?