sloe bicycles raleigh randonneur

I've edited my comment, because I was wrong..
But I calculated it first, which was why I said around 20%.
At some point you might like to try the Continental Grand Prix Urban. They're branded as 35mm, but my pair came up around 33mm on 19mm internal rims.
They ride incredibly smooth on tarmac and gravel, and I didn't have single puncture with mine.