So these Continental Diesel tires are just right for the kind of trails I ride, however I'm wondering if they're too wide for my bike. I ride a Trek 4300(2009). My normal tires are 26x1.75", these tires are 26x2.5". Is this too radical of a size difference? And just one other question do I HAVE to run wider tubes or are 1.5-1.75 fine? Continental Bicycle -Diesel
I run 27x2.25s on my 09' Trek 4300 disc and i have a mile of clearance left over with them. And yeah, like Mr. hack says, you need new tubes.
1.75" tubes are too small, but don't worry about finding tubes that are rated for 2.5" tires. 2.2-2.35" are fine. Most 2.5" tubes are made for downhill and are heavy and expensive.
So instead of the Diesels I went with Bontrager XR4's. They were what I was looking for, and defiantly fit my bike. The awesome owner of my LBS showed me the actual with of the diesels and it turns out you only have a 1/4 inch of clearance, which is not enough for pedaling. Plus, the XR4's are much lighter, the diesels would have added 4 pounds!!! So it worked out for the best that I went up there. I posted some old, new tire comparison photos.