Dropout size issue

Roasted

Kona Fan
Assembling a bike and the dropout is norrower at the bottom than at the top on the drive side. The bottom is 9.54mm and top is 9.95mm. Hub fits fine on the non drive side but won't go in the drive side. You can see in the picture that the dropout is slightly narrower than the hanger.

What would you do? I have a feeling that I know what the answer is.

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To my eye, it looks like the replaceable drop out isn't aligned correctly, causing the problem. Can you loosen the bolts, adjust and tighten up! I'd suggest loosening, popping in the wheel to align it, then tighten the bolts but it looks like the qr could prevent this.

Had a similar issue on a carbon frame. Replaceable dropout design was a bit pants, had a single bolt that acred a bit like a pivot and the overall shape allowed the drop out to move, mis-aligning the rear axle. Had to file the replaceable dropout so when it was settled in position, it didn't push against the axle.

In your car, looks like if the dropout sits as pictured, you may need to file a few mins of the frame.
 
We often find with new frames they've been bashed, sometimes before painting, closing the dropout up enough to pinch on the axle.

Often a whole lot worse than this.

Alternately it could just be the hanger taken the dink.

Either way you can be sure when these parts were cast or machined, they were parallel.

If you're super bothered and it's new, you could ask for a replacement.
Otherwise a touch with a file and away you go.
You can eye up the sides by looking across to the lh dropout to check, but it's almost certainly the back face pushed in.
 
It's a used steel frame so it's possible it's had a knock in the past. It's just been freshly painted so I really don't want to take a file to it, but it is in a hidden area. The hanger is brand new hanger which has been drilled for lager bolts.
 
The spindle will have the paint off pretty quick anyway....so grab a file.

You could heat the frame cherry red and bend it a bit....but that's really going to loose some paint.
 
I've managed to fit the 10mm hub. I put the axle in the dodgy drop out first and then dropped in the OK side. A bit of a faff but seems to work ok. I had hoped that I wouldn't have to take out the wheel very often, but I fitted a 180mm disc and I actually need a 160mm.

If it becomes a problem I will get the file out.
 
As said, the liklihood is that it's suffered a whack against the rear dropout edge at some stage, quite common occurance when working in bike shops. I just use a prybar to realign things.
 
Freshly painted frame. Quite possible just a really thick coat at that point. That area is going to be sprayed from a few angles to cover it properly. Go gently with some wet and dry rather than a file and see how that works.
 

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