700c or 650b wheels – what should you go for?

We’ve designed a number of our frames to accommodate both 650b and 700c wheels – the Mehteh, Kepler and Big Bro will all happily take both wheel sizes (referred to as 27.5″ or 29er in the mtb world). So naturally we get a lot of our customers asking what the benefit of each wheel size is and therefore which they should choose. There’s a huge amount of debate about this online so we’re not aiming to “solve” the question – however we thought we’d show you a couple different wheelsets on our gravel frame the Mehteh and give our opinion on the subject below…

To put it simply a 650b wheel has a smaller diameter (584mm) than a 700c wheel (622mm) – the smaller diameter of the 650b wheel allows you to put a higher volume tyre on your bike while maintaining a similar overall wheel size to a 700c wheel with a narrower tyre. The only limitation is that the frame has the clearance to accommodate the tyre width. Always check the frame spec to see what the max tyre size is.

Have a look at the two pictures below – the first is a Mehteh fitted with 700c wheels and 40mm tyres and the second is the same bike however fitted with 650b wheels and 47mm tyres – the difference is relatively subtle however the riding style of each bike is very different.

Before we discuss the benefits of each option we should point out that this is simply our opinion based on our own riding experiences…

A 700c wheel is the go to standard for road and cyclocross bikes, the thinner tyres mean less rolling resistance and more momentum which is suited to tarmac and not-too-technical gravel terrain. However the larger diameter does mean the wheel has good rollover capability, if you then combine this with a gravel tyre like the WTB Venture in 700c x 40mm (as we’ve used in the picture below) you’ll have a very versatile bike. Fast on the tarmac whilst still giving you a lot of confidence when you hit some gravel.

If you go with a 650b wheelset you’ll be able to fit a higher volume tyre in the same frame – this means you’ll have a larger connection point with the ground giving you better grip when off-road. Also, having a larger volume tyre means you can run your wheels at a lower psi which is better suited to riding on rough terrain. The low pressure allows the tyre to conform to bumpy and uneven ground, giving you better grip and bump absorption – this is super important on longer rides where bumpy trails can really sap your strength!

So, if you’re asking yourself whether you want a 700c or 650b wheelset on your bike you really need to think about what riding you’ll be doing most of the time. If you’ll stay on mostly smooth tarmac and gravel, rarely venturing onto the really rough stuff, then we’d probably recommend going with 700c. However if you’ll be spending a lot time off-road and can’t help but explore that single track weaving off into the trees then you might appreciate the comfort and grip that a higher volume tyre will give you.

And if you want a bit of everything why not get yourself two wheelsets? The beauty of disc brakes is you can easily swap one out for another. No need for two bikes, we’ve designed our frames with versatility in mind – ready to tackle whatever adventures you throw at them.