Schwalbe have identified a problem apparently with a particular batch of their Ultremo R tyre. I bought a pair of these tyres just before the defect was identified and they were delivered 24 hours before the problem was made public. I have been observing and testing these tyres since and had been pleased with them.
When the problem was identified I wrote to Schwalbe quoting the tyre batch numbers and the reply they sent was as follows:
Thank you for contacting Schwalbe North America. Your tires are OK. The production codes of your tires point to a very recent production, well after the issue was found out and changes were implemented. We apologize for any inconvenience this has caused and trust that you will be completely satisfied with your Ultremo “R” tires.
Reassured I continued to use the tyres and continued to monitor them carefully, I have now done about 250 miles on them.
I was riding today and had just completed a long steep descent at just under 50mph when I felt a "bumping" from the back wheel. I stopped to investigate and the tyre is failing.
This tyre fault could have killed me. Note the following:
1. As soon as I knew there was a problem I contacted Schwalbe.
2. I was assured that my tyres were not from a defective batch.
3. My tyres were well past the 100 mile period when they are supposed to "fail if they are going to fail", according to Schwalbe.
4. I have only done 250 miles on the tyres.
5. The tyres are perfectly fitted and undamaged.
6. The rear tyre is on the point of complete and catastrophic failure which happened suddenly as I had inspected them before I set off, the bulge appeared during the descent, there was no "bumping" during the ride prior to that point.
Based on this experience I will not be using this product further, my opinion is that a rider cannot have confidence in this product. I would advise anyone using these tyres to think very seriously about the safety of this product before continuing to use it. In the end it's a personal decision.