All Terrain Bike

[KDean]

Would you count the Nomad mk2 as an  ATB ?

[Danneaux]

I certainly would, because mine has been over...all terrain. 

Tires and tread are a determining factor as well.

Best, Dan.

[WorldTourer]

I rode the Baja Divide, one of the world’s most grueling bikepacking routes, last season on a Nomad Mk3. There is nothing about the Nomad frame’s geometry and strength that makes it unsuitable for bikepacking routes. It all comes down to the gearing and tires you install on that frame. Of course, Thorn’s own builds are generally with gentler terrain in mind.

That said, the Mk2 is inferior to the Mk3 in a number of ways, from the bad bottom bracket design (which makes the elliptical shell a wearable part) to the rim-brake-only Nomad Mk2 fork. One of the best features of the Mk3 is the seatstay splitter for a belt drive – it was great to cycle across 2000 km of dusty and sandy desert terrain without having to clean a chain.

[PH]

It isn't the classification I would grab for when describing it, but these things are vague enough that many bikes fit into multiple ones.  I prefer to approach it from the other end, if you say it's an ATB would I have a reason to disagree? No.
It's a term that hasn't been much used for a while and seems to be coming back into fashion, particularly on the trendy websites:
https://bikepacking.com/plog/atb-manifesto/

EDIT - For the princely sum of £3.50 I've just bought a copy of "Sloane's Complete Book of All-terrain Bicycles", a 1986 edition.
I read a copy a decade or so ago, when I was deciding on the design for a custom ti bike, it was a bit dated then.  Maybe if ATB's are coming back into fashion I should buy them all up and promote them with a trendy spin!

https://www.amazon.co.uk/Sloanes-Complete-Guide-All-terrain-Bicycling/dp/0671532332

[mickeg]

Would you count the Nomad mk2 as an  ATB ?

Yup.  But, it is not a fat bike with the super wide tires that float over snow.  I run 57mm wide tires on mine, I think that is the upper limit.

First through third photos are with the stock fork fitted.  A 100mm suspension fork can be fitted to it, but it has no rear suspension.  Fourth photo has a front suspension fork on it.  That said, it may be hard to find a 26 inch suspension fork that has sufficient steerer tube length for a larger size frame, as such forks are pretty rare now that everyone has shifted to 27.5 or 29 inch wheels.  The fork I have in the photo was bought in 2014 and at that time I was having trouble finding one with sufficient steerer tube length.

Thorn advised against drop bars for this model, but that is what I want for strong headwinds.  And Thorn is not a fan of kickstands, which I fitted to mine.

The Mk II was sold either as a complete bike built to order or as a frame and fork, I bought the frame and fork, built up mine from parts.  You will find each Mk II differs slightly because of this.

Many Mk II were build with CSS rims that have an extra hard wear braking surface on the rim, thus rim brakes do not wear out the rims.  But CSS rims are no longer available.

I have not had any problems with my eccentric bottom bracket.

It is a heavy bike, if you are in a race you want something else.  But if you want a load carrier, it is great.

[PH]

Worth a short read on the history of such bikes:
http://www.63xc.com/talljames/cleland.htm