Jones Ti Spaceframe

Looking at the current STW thread on Jones, now topping 130 posts is easy to forget one thing, the Jones is a just a bike, nothing more, nothing less, it’s not a magic bullet, it’s not a cure for cancer or create world peace.

Ok now we’ve got that sorted, here goes………jones1

Concept – A fully rigid bike with some built in ‘give’. To keep things simple and create an enjoyable involving ride that will test your skill and reward your efforts.

The Design – The frame set is designed as complete unit with the fork and handlebars, so the geometry of the frame and fork complement one another. Perhaps its most unique feature is the truss fork. This is designed to be super rigid and precise in its handling with 55mm offset to quicken up the steering. The frame is designed to be laterally stiff but with some vertical compliance, a video on the Jones website shows this, with the chain stays flexing up and down and the seat post moving back and forth. This, combined with a long flexible 27.5mm seat tube takes some of the sting out if riding a rigid bike. It’s designed as a 29er, so the larger wheels roll better than 26″ wheels. The frame set sets out to solve the challenges of 29″ wheels. The wheelbase is kept very short, with a bent seat tube to allow for short chain stays. It’s wheelbase is actually shorter than my 26″ full suspension bike. A short wheelbase equates with nimbler handling. Another issue with 29″ wheels is flex, with the Jones, the front fork is designed to take a 135mm front hub, this allows for a dish-less wheel that is stiffer and stronger than normal. A specially modified 6 speed cassette is available to fit on a single speed hub to allow for a similarly stiff dish-less rear wheel. The wheels are built from 35 or now 50mm wide rims  (the frame is designed to take 2.5″ tyres) – this spreads out the profile of the tyres and allows for lower than normal pressures  – typically 18psi for the front and 20psi (somewhat less with 50mm rims), with tubes, increasing grip and comfort.

The accumulation of all these design choices, (29er, stiff direct fork, large volume tyres at low pressure, wide rims, vertically compliant frame, short wheelbase) is a bike that dances through twisty singletrack with aplomb and is simply a joy to ride.
jones2
Fat – Another option is to run a FAT tyre up front, a 26″ rim, (typically 50mm to 72mm wide rims are used) and tyres up to 4.8″ will fit. The fat tyre on a 26″ rim adds up to the same diameter as a 29er wheel. I usually run a 4.8 Big Fat Larry tyre at 7.5psi with a wide 72mm rim which allows for low pressures whilst maintaining stability. These tyres are great fun to ride – trail buzz is nicely absorbed and it has the feeling of being able to roll over just about anything – it’s pretty confidence inspiring. The downside of these tyres is weight and rolling resistance – this feeds back as a somewhat slower steering feel, it takes some adjusting to but once dialled in, it’s grin inducing. The tyres offer bucket loads of grip in winter slop too.

The latest option is the 3″ 29er+ Knard tyre by Surly – which manages to combine the best of both fat and normal tyres – it’s a real blast to ride, fast responsive handling, plenty of grip and some of the cush offered by fat tyres – it’s a winning combination.

The final feature is the “H” bar, which is designed for a natural hand position (unlike normal handlebars!) – I find them great, but they’re marmite – that’s for sure!

I thinks that’s about it.

Ashley

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