Now my groad is up and running, I’ve been having a bit of a thought experiment. While riding the bike on in gravel mode (40mm tyres) on a particularly bad section of road between bridleways, I was struck by how much smoother the ride was and how I hardly noticed the poor surface.
This led me towards the idea of trying some 32s or even 35s as slicks for the road. The road surfaces round here (especially on the quieter country roads) are often indifferent at best, not getting any better, and even 28s in tubeless are not always the most comfortable.
Now, let me be clear, I don’t race, and while I do some fast-ish group rides and have target times in mind for a few forthcoming sportives, absolute speed isn’t everything for me (just as well really). So with that in mind, losing a little pace shouldn’t really bother me.
But… I work quite hard for my current fitness and speed, indifferent as it is, and I’m loathe materially to sabotage that.
My gut and research seems to suggest that at 30mm, any speed losses would be trivial, and perhaps even at 32, but at 35 I’d expect to notice a fall-off.
So what I’m asking is this: has anyone in a similar position actually put wider (over 30mm) tyres on their road bike, and how did you find the experience? How much, if any, speed did you lose? If it helps, I’m not quite 4w/kg, tend to average 27-29kph over 2-4hrs riding solo on fairly lumpy terrain, 1-2kph faster in a group, and ride Aeolus Pro 37 wheels (28mm external width).