33.3 recurring: Rivendell Jack Brown and the mathematics of plush

Two immutable laws were at play today. 1. Buying your own Christmas presents is always best. 2. Spending money on tyres is the most efficient way of transforming your bike.

I squared the power of these two laws recently with the acquisition of a pair of Rivendell Jack Brown Green tyres. Now the thought of opening a pair of tyres wrapped in Christmas paper might not appeal to many. Opening a pair of tyres that you bought yourself is surely more tragic? Nonetheless the childlike joy of anticipation has kept me going since I clicked ‘Buy Now’ on Planet X’s website during their Black Friday Fibonacci sale a month or more ago.

“Math is a wonderful thing”, to quote Jack Black, and Jack Brown also knows a thing or two about the magic of numbers. What we have here is a 700c tyre in a Goldilocks 33.3mm width. Why is 33.3 just right? Because it will fit a huge range of bikes, from 1970s and 80s ‘road bikes’ through hybrids, tourers and cross bikes.

It is also a width that won’t intimidate dyed-in-the-wool 23mm riders, in spite of high performances tyres being available in motorcycle-like widths for many a moon.

But it’s when fat is combined with thin that the magic really happens. A fat, slick tyre with a thin supple carcass is the apogee of road/cycle interface. Jack Brown ‘Green’ is a fat skin wall with a thin tread, high thread count, Kevlar bead and no puncture resistant belt and as a result, weigh a paltry 350g apiece. Rivendell also produce a ‘Blue’ version with a Kevlar belt for the puncture-anxious.

But enough of the numbers and specs. How does the maths work out on the road?

In short. Oh. My. Levels of plush that one only dreams of. Quick acceleration. Floating over irregularities like a pneumatically-suspended god. A rounded profile that begs for Jan Heine-like angles of lean. Tenacious grip on many surfaces. I rode this very day through water, ice, autumn leaves, puddles, gravel and more and not once did Jack’s chequerboard tread complain.

Then there’s the looks. Simultaneously channeling 70s road bike and Dugast tub, the Panaracer-made Jack Brown is a quality handmade in Japan thing, looking like a snake that’s shed its skin in the packet but on the bike like the bulbous, canvas-sided loveliness that graced Eugene Christophe et al’s Tour de France whips.

But inevitably we must come back to the numbers. What price for this best of all worlds performance? Currently £29.99 from Planet X , Fibonacci sales excepted.

My advice? If you’re fat tyre curious, call Jack. You won’t be disappointed.