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Poll Time: 650b or 27.5 - What the hell do we call these wheels?

13:15 17th May 2013 by Ed Haythornthwaite


We’re fed up of companies calling the ‘in-between’ wheelsize different things, we just want to pick one and stick with it. But which one should we use? Is it 650b, or is it 27.5? You decide!

If we manage to sort this one out then maybe we can move onto all the other oddities in our sport like is it a 150mm travel bike or is a 6″ travel one? Actually scrub that, I can’t ever see us sorting out the whole metric/imperial nonsense, but let’s at least try and nip this one in the bud before it gets even more out of hand…

What should we call the 'in-between' wheelsize?

View Results

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  1. Chris Keeble-Smith

    Seems to make sense to keep it simple with imperial units for all three wheel sizes. 26″, 27.5″, 29″

  2. Ross

    If everything else is named in inch size why the hell would we call it 650b?

  3. phil

    As they don’t measure 27.5″ I don’t see why we should call it that.
    Maybe the marketeers want to disassociate with the roadie-esk standard but the fact is 650b has been around longer than mountainbikes. We only got 26″ because Joe Breeze and Gary Fisher couldn’t get strong enough rims and tyres to suit their needs

  4. Ed

    Thought I would cut and paste this from good old Wikipedia to fire up the debate even further. I mean after reading this I’m thinking maybe we should go with the true 584mm measurement, or should we even be going down the 23″ route?

    26 inch / ISO 559mm [edit]
    26-inch clincher tires (with inner tubes) are the most common wheel size for mountain bikes. This tradition was started initially because the early mountain bike pioneers procured the wheels for their early bikes from American-made bicycles rather than the larger European standards in use. The typical 26-inch rim has a diameter of 559 mm (22.0″) and an outside tire diameter of about 26.2″ (665 mm). Increasingly common are tubeless tires conforming to the UST (Universal System Tubeless) standard pioneered by French wheel manufacturer Mavic in conjunction with tire manufacturers Hutchinson and Michelin.

    27.5 inch / ISO 584mm / 650B [edit]
    Main article: 27.5 Mountain bike
    27.5-inch mountain bike wheels[29][30][31][32][33] (which some also refer to as 650B[34][35]) use a rim that has a diameter of 584 mm (23.0″) with wide, knobby tires (~27.5 x 2.3 / ISO 58-584) are approximately the midway point between the 26-inch (ISO-559mm) and the 29-inch (ISO-622mm) standards. They carry some of the advantages of both formats, with a smoother ride and larger contact patch than a 26 inch wheel, and more stiffness and durability than a 29″ wheel. As 27.5-inch wheels have just started to be embraced by larger manufacturers, one of the primary disadvantages has been a reduced selection of compatible frames and forks. However, an increased availability of 27.5-inch forks, wheels, tires and tubes is expected in 2013.

    29 inch / ISO 622mm / 700C [edit]
    Main article: 29er (bicycle)
    “29-inch wheels”, which also conform to the popular 700C (622 mm diameter clincher) wheel standard are becoming more popular for not only cyclocross bikes but also cross-country mountain bikes. Their rim diameter of 622 mm (~24.5 inch) is identical to most road, hybrid, and touring bicycle wheels, but are typically reinforced for greater durability in off-road riding. The average 29-inch mountain bike tire has an outside diameter of about 28.5″ (724 mm).

  5. Scott Malcolm

    Can’t we just stick with standard 26

  6. Boredofwheelsnow

    Small, medium, large I don’t care how about a day without mentioning wheels

  7. Chris Pleass

    The real question is ‘six filthy b’ ’650 cheat’ or ‘six fifgay b’. For people such as myself who consider them cheating and not mountain bikes. (Same way a bike with 20 inch wheels is not a mountain bike)

  8. Chris+Pleass

    Also what the hell does the 650 or the b mean?

    1. Dirt

      Something to do with the width of the rim isn’t it?

  9. sx trail

    Where’s the “who gives a shit button?”

    1. TimBud

      thats the 3rd option fella ;)

      1. sx+trail

        The page wasn’t working properly…

  10. sx+trail

    Now it works! Go figure!!!

  11. sx+trail

    I see that it’s not loading properly again.

  12. benkilbee

    I actually quite like the way all the various parts of a bicycle are a complete mish-mash of imperial, metric and even dedicated measurements (inch gear). Seems to reflect the rich diversity of bicycle culture and history.

    At the same time I can also see how it could all be waaaay simpler for everyone to understand if we just stuck to one measurement system. But that’s not gonna happen anytime soon is it…

  13. benkilbee

    Don’t think I’ve ever seen a poll that had such even results! 34%, 33%, 33%!!! That’s crazy! :D

  14. ryan

    either 650b or 27″. It’s not 27.5″ so why call it that….

  15. Bruce

    Well personally i think 650b. Not 27.5 because its sounds lame. I dont think 650b wheels will go out because its a split halfway betweeen 29 and 26. Say your rly small but u want a bigger wheel size for xc. Well? 650b. Even though why is it called 650b


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