The wheel wars get hotter every day. As well as 29-inch and good old 26-inch, the latest contender is the intermediate size 650B, which gives an overall tyre diameter close enough to 27.5 inches that ‘27.5-inch’ is what everyone’s calling it if they haven’t memorised old French tyre sizes.

There’s heated debate about whether an intermediate size is a good idea or even necessary. Californian bike maker Intense is convinced though. They’ve just announced the Tracer 275 and Carbine 275 with 650Bs.

Intense marketing manager Scott Sharples says: “If the industry had to decide on one wheel size, I would vote for the 27.5, without hesitation. It is just as much fun as a 26, but faster. If I had to pick one bike from my quiver right now, it would be my Tracer 275. Without a doubt.”

Intense president and head designer Jeff Steber decided to make a 650B macine while travelling. A few weeks later, he was riding the first prototype.

“One of the advantages of having our own factory on-site is that we can put plans into motion right away,” says Steber. “I can visualize it and can make the first prototypes a reality within a very short window.”

Intense claims the advantages of the 650B size are that the “wheels roll right over the chatter, float through the sand and still rail into the corner without the overbearing feel of the 29er. The best part is, you don’t’ have to adjust the way you ride on the 275. You can hop right on and feel instantly comfortable with the bigger wheels.”

The Tracer 275 has travel adjustable between 5.5 and 6in, 17in chainstays, a 13.3in bottom bracket, cable routing for RockShox’s Stealth Reverb dropper post, Intense’s G1 replaceable dropouts and a modified geometry 67-degree head angle.

Intense has also announced a 275 version of the Carbine carbon fibre trail bike. By modifying the dropouts, Intense has been able to fit a 650B wheel into the existing frame while giving sufficient tyre clearance and good handling. Intense says the converted carbine will take a 2.35in tyre.

Everything old is new again in the bike industry. Tom Ritchey was building mountain bikes with 650B wheels in the early ’80s, until the supply dried up of the Nokian Hakkapeliitta tyres Gary Fisher was importing to shoe them. That means 650B’s not actually new, and had history gone a bit differently, we might never have had 26in-wheeled mountain bikes at all!