I think the problem is with the straight head tube, rather than geometry. You’ll have to find 27+ / 29 forks that haven’t go a tapered steerer.

The longitude is what it is…. Don’t change it…. Embrace the rigid and just run a bigger tyre with less pressure……

I’ve still got the stock tyres too which are fine, but will change to something in 3.0″ when they wear out. A<span style=”font-size: 12.8px;”>t the moment I’m actually using a 29er wheelset with spiked tyres for commuting in Oslo, it’s a great bike for doing everything on!</span>

Strip it, transfer the parts to a tarn frameset ( there are a few going cheapish at the moment ) and give the longitude frame to me.  Along with the Croix de Fer.  HTH.

It isn’t all about the N + 1,  it’s about another one.

Tarn is 148×12 longitude is qr both ends.

I thought longitude was qr at the back and TA at the front or something equally weird.  I won’t tell OP if you don’t, though.

Out of curiosity, what year is yours?

I’ll have to check the new ones, it is the one thing that has put me of the longitude.  I’d like to be abke to mix and !atch wheels with my other bikes. Well that and the slightly odd Geo.  The high standover, and the relatively short reach compared to top tube length, im not sure how well I’d get on with it

Yep, 2017 and newer are 100mm/135mm x QR. The Longitude angles may look odd on paper, but it fits and rides great. Standover is no issue, in fact it has the lowest standover of any of my bikes (not as low as a Tarn though). If you want a bikepacking/touring bike it is hard to beat, if you want a trail hardtail I would look at other options.

Cheers guys that’s really helpful.  Sorry to OP for the hijack.

I like the long and low thing but also want to use it as a winter/commuter/ everything bike.  I am becoming more aware of my own mortality so don’t do the stuff I used to do in my non-sus, non compact Geo 90s mtb.  Occasionally I ride a trail, manual, bunnyhop, take small jumps for fun so really don’t need a full on trail bike.  The longitude seems to fit all of that, like the Kona Unit and Pine mountain and still enough in it to do the occasional stupid.

I’m torn between the s and m though.  M gives more reach and a really long TT with the laid back seatpost.  The standover numbers worry me though.  They don’t look anything like as tall as they say, the Geo is similar to other bikes with much lower quoted standover.  I suspect they must measure much closer to the Head tube than others do to get the numbers they do.

I think a Tarn should be really fun but the boost spacing puts me off.

Is that a 32″ crotch to floor or 32″ trouser leg.  If that’s not too personal a question.

I would go for the bigger size. It’s true that it’s long and low, but it’s a bike you sit “in” rather than on which is great for riding longer distances. It’s also the kind of bike that works really well with a swept bar like a Jones (I have an OnOne OG bar on mine coz I’m poor) which will bring your hands backwards. Also a larger size means you’ll get no toe overlap – I have 29″x2.1″ tyres plus full mudguards on at the moment and there’s plenty of clearance.