Looking inside my rear 142mm axle there appears to be a line running around the internal circumference in the middle, giving the appearance of a two piece axle, is it a perfectly formed crack or a machined mark, my boost pro4 rear doesn't have this mark.
They're quite easy to knock out using an appropriately sized socket and a rubber mallet, so if you are worried then I'd take a look.
Does your back end seem less stiff than normal, or is it creaking?
Pro2s were prone to cracking their axles because they were quite thin. Pro 4s less rather less so. It's certainly possible, but one of the main drivers for the pro4 replacing the pro2 is said to be exactly this.
You might be looking at a crack, you might be looking at a machining mark.
one of the main drivers for the pro4 replacing the pro2 is said to be exactly this.
I thought that was the pro2 - pro2 evo change? The pro2 axle was fine until you used the 12mm version which had very thin walls.
Theres no performance issue or creaking, I'm just thinking 'that line wasn't there before', looks like I'll be dismantling and checking to be on the safe side, I'm putting a new wheel on anyway, just didn't want to risk bearing damage by tapping out the axle for nothing.