I’d like to upgrade the wheels in my surly ecr, the wheels I have are 142×12 rear and should go straight in.

However, I think I’m going to need a bolt up thru axle that bolts up from both sides as the frame has horizontal slot dropouts.

Surly do one but I can’t see any stock the other option is a cheap Chinese QR stye thing which I’m not sure I could trust when on multi day trips alone.

Any thoughts or suggestions gratefully received

Hmm – I was about to advise you to check out WolfTooth/OneUp/Burgtec for axles, but when I googled for a Surly Axle, I foudn the link below, looks like a proprietary axle so you might be stuck with Surly’s own one. It’s in stock below, at least.

https://www.bike-components.de/en/Surly/Gnot-Boost-Rear-Thru-Axle-p75518/

Do Robert Axle Project make something to fit? They have all sorts, SJS cycles also sell their axles.
https://robertaxleproject.com/

Thanks George, looking at the photo of the axle on that link it appears that the axle does both 142 and 148 which is what’s in there now so should just swap straight over.

An unexpected, very welcome outcome to this post.

Thanks all.