Originally Posted by
johngwheeler
I weigh 71 kg (158lb). On hard packed dirt, the 32s are fine. On loose gravel, sandl they lack traction and stability.
Would 40mm tyres be a lot slower on the road?
Than 32mm? not really. It depends
There are some factors to consider.
1) carcass construction is the biggest. With the same carcass & tread, they don't roll a lot slower. Most larger tires have stiffer carcasses (and often different tread) that can make them roll slower. companies like compass specialize in tires that don't have these disadvantages compared to a smaller tire.
2) bigger tires are heavier, and will accelerate slower every time you stop.
Yeah, I ride 32mm on hardpack, and 40-45mm on dirt and sand. It makes a difference.