I've just fitted a new WTB Nano 700C x 40, and there were a couple of issues, one minor, one major. The side wall had a pin prick hole in it, which I guessed correctly would be easily sorted out by the sealant. This issue unfortunately took my attention away from the bigger picture, and after I'd added sealant and span the wheel fitted to the bike, it looked at first as if the wheel had a significant buckle. On closer inspection, one portion of the tyre measured 35mm from the rim, while the rest was 40mm. Obviously it's going back, but has anyone else had issues like this? I suppose that I've been lucky that in 40 years of messing about on bikes, this is the first time I've encountered something like this.

I've seen the same on both Maxxis and Schwalbe tyres.

Are you sure they’re seated properly? Did you get the seated bang? I’ve seen that wHen a tyre isn’t quite in place evenly all the way round.

I didn't get the seated bang, but it was holding air. I did unseat the tyre and try again with the same result though. Even with the previous tyre (Maxxis Rambler) I didn't get the bang. I put that down to the tyres being mounted on old rims that were made long before tubeless was a thing.

Continental Mountain Kings years ago. Bought a load on offer from CRC. Was a super offer. But all turned out to be warped (except 1... so I think that was 4 that were wobbly).

Glad you noitced it straight away as mine were for bikes that I built over the months/year for others so never caught the problem straight away. Then for many years stayed away from Conti but I reckon it wss pribably just a batch issue and hence the reason they sold em off so cheap!

Did you get your super cheap or reasonably priced

The WTB Nano was the cheapest I found after a quick Google search, but not shockingly cheap.
You've got me wondering now though Shaf. I've got a couple of Conti Mountain Kings in reserve (that I got for very good price last year) for when the Maxxis Ardents on my mountain bike wear out. Fortunately the Ardents are proving to be very hard wearing, despite being ridden on more tarmac than I would like for off road tyres.

Conti X=King on the back of my OO Fatty is warped, but side to side, rather than up and down, if that makes sense. Spin the wheel and it looks like a massive kink in the wheel. Dont notice it riding mind.