I noticed my back tyre has hollow knobs and I can't remember ever seeing this before. Some of the knobs have turned out to be hollow inside. I know YGWYPF, my questions are:
- Is it normal? I got no meaningful results with google.
- Is it desirable on a budget (even cheapskate really) tyre? It wouldn't surprise me on a £££ model, but in this case my guess would be that it would not meet the balance between extra cost of manufacturing complexities vs the savings on raw materials.
- Shouldn't the label say the knobs are hollow? My loose thoughts would be that this has a bearing on a user's ability to assess things like performance and remaining life? Even if it's the subconscious visual assessment of these? I bought this in the UK but it's a global brand (and so is probably the model).
I'm aware many on here would argue this tyre is way overdue for replacement, this is not what the question is.
Edit: Clarification in response to some early comments.
- I can't tell for sure if this is a manufacturing defect, it might be, but I think this is part of my question really.
- The holes do not seem to go through the casing to the tube inside. The best way I can describe it is that it seems like they are hollow blocks/knobs glued onto a slick tyre. It also seems that the hollow space inside the hole is bigger that the opening that has been created.
- I estimate I've ridden 100 to 1000 km on this tyre, 95% tarmac (from dry to heavy rain), 5% well compacted gravel path, very little harsh braking. Estimates are very rough because I don't use any tracking and my cycling comes in irregular spells of commuting.
- They do indeed seem irregular. To me, this could equally indicate "unintended error in manufacturing" or "intended by design but poorly executed". The photos are a decent indication of the number and spread/distribution around the whole tyre. I'm fairly sure I didn't ride over enough broken glass (or similar) for that to be the main cause.