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Donnelly BOS Tubeless CX Tire

Review: Donnelly BOS Tubeless CX Tire

scottmares's picture

We Liked

  • Thick tred
  • large side knobs
  • Tubeless ready
  • Arrow center tred

We Didn't Like

I would like to change this title from “What we don’t like” to “What we would like to change”. We would like the tire to be open more in its tred. Right now to us the tire is inbetween a all around and a mud tire with the current tread spacing. Our recommendation to improve this tire to true mud awesomeness is to reduce the center and side knob count by one and then respace. This would open it up and allow the mud to clear off the tire before the tread bites the mud again. Packing of mud will not allow the tread to do its job of edging and reduce its grip and bite in the brown slippery goo of cyclocross.  

The Final Say

We love cyclocross here in the Pacific Northwest and we love it when it's muddy. We see all sorts of mud tires and the biggest improvement in cyclocross tires came a few years back with the PDX. It's no coincidence that Donnelly was also involved in the PDX tires developpement when you take a close look at the BOS. Now After using this tire in a couple of different situations I can say that it is my new favorite mud tire for a couple of reasons. The tread is aggressive and deep. This deeper tread allows it to dig in. Over the years I have noticed that the PDX tread appears to not be as deep as when it once was. I found the tread of the BOS really well suited to the slick semigrass hills that we have around here. Because of the robustness of the tread the BOS will also work well in rocky conditions as we found out. The Final race of the Cross crusade was at Barton Park this year and that race is in a rock quarry. So there was plenty of loose gravel and dirt with some larger rocks to deal with on a mostly dry course. I went back and forth between a file tread or the BOS and ended up choosing the BOS. It was a good choice in that the tire was really good at the changing surface conditions from gravel to dirt to mixed. Turns out that the BOS is really an all around tire that does really well in the mud.  

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