unterhausen

I'm somewhat curious about why you chose this forum, instead of, say, the gravel forum. But at those distances, I would just go with gravelking small knob and be happy. I have really good luck with them on my gravel bike. I use that bike for all kinds of riding, not just gravel. They definitely cut down on the stress when riding gravel or bad surfaces and they aren't super slow. They might be too draggy if you were riding 300km mostly on roads, or something like that. But I have ridden them on 200km mixed surface rides with some success. For mostly road rides with some rail trail fine gravel, I have some 40mm Maxxis velocitas.