I had a shop convert my Avanti mtb to an ebike. The tyres were replaced (from knobbly to road) as part of the job. I’ve ridden it maybe 5 hours tops for a 3 commutes and a tame off-road ride locally.

I’ve just noticed this split on the outside of the tyre, close to the rim. Lucky I did, because I was just about to take my baby out for a ride, after recently getting a seat added to the back.

What could cause this? I have had my tubes pumped to max 60psi... the bike it stored in an outdoor room that can get warm in summer (though usually doors are open). enter image description here

  • 1
    Purely bad luck, 100m out of the shop is enough to cut the side-wall on a shard by the way it looks.
    – Carel
    Jun 6, 2021 at 7:17
  • @Carel: The strange thing is that there is no scratch marks or abrasion anywhere along the cut. Maybe a knife attack, manufacturing defect or really bad luck with a broken bottle or very sharp rock.
    – Michael
    Jun 7, 2021 at 6:03

1 Answer 1


Contact your bike shop ASAP - I'd politely ask for a replacement under warranty, looks like a possible manufacturing defect in the photo, unless it happened to get slashed exactly between the threads.

Or could there be someone stabbing your tyre with a sharp craft knife when its parked somewhere ?

You're right not to ride that tyre as-is - the inner tube seems to be visible already and it won't take a lot to herniate out.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.