So I come from a trials background where reach was calculated completely differently to regular bikes and I'm slightly confused.
My MTB is a 2018 Jamis Dakar A2 in XL, which according to all the reviews I've read, has a short reach in comparison to similar bikes of 485 (and it feels pretty cramped even in XL).
I've looked at other bikes to see what kind of reach they have if it came down to switching and all the numbers I can find are even smaller, for example the closest comparable bike the Bossnut is 463?!
If anyone could explain I'd be very grateful!
If you havent already look at geometry geeks where you can compare bikes and they have a handy guide to key metrics also
I'm assuming you're quite tall if you ride an XL and find it a little small?
Does it feel cramped when seated or standing?
I just had a look at the geo for that bike and while the reach is quite long the stack height is quite low, that probably makes it feel small. The diagonal distance between the BB and the top of the head tube is the major factor in how big a bike feels in my experience.
Was going to suggest looking at geometrygeeks. Great website.
485 isn't short by modern standards. Yes, there are much longer bikes, but most aren't. I'm 6'1 and have a hardtail with that reach and it feels long and roomy for me.
the latest Bossnut in XL is 476mm.
this is still very conservative, i ride a large in all my bikes with reach numbers around 470-480mm.
manufacturers are all over the place with bike sizing and recommended fit etc. this is often the case with the same manufacturer and different models.
the problem in the past though was that we were generally restricted to seat tube length, if you bought a bike that had the reach you wanted then you couldnt get your feet on the pedals, so things are much better than they were, and with 'large' bikes coming in with reach numbers from 440 to over 500 the size on the sticker means nothing, so it obviously helps to know what you want before you go out and spend.....and what you want will depend on what type of riding you are doing.
Is a vitus escarpe a reasonable comparison with the jamis? Seems similar to a bussnut ie 27.5 trail bike. That bike has a 510 reach in xl and 482 in l. Size up in that to get the room you want? 480 seat tube on the xl so prob limited to a 150 dropper.
I would say the Escarpe is probably a bit of a cut above the Dakar in general. Think it’s got a bit more travel and it’s a bit burlier. Pretty decent whilst still being good value. They’ve gone carbon mainframe for 2021 rather than alloy and they look pretty good.
Geometry is a minefield - as someone said above 485 is a fair reach but it depends how tall you are. It looks like the Jamis has a fairly low front end despite the long reach so that could be making it feel small to you potentially.
It’s not just outright height that defines what reach / stack etc you should go for, but also your proportions and riding style.
On the manufacturer of my full suss bike I should be on a Medium-Long size, but I found that too long a reach (481mm) because I’ve got relatively long legs for my height but short arms. So I sized down to a medium.
Also there’s a difference in the effect of reach between a full suss bike and hardtail. Hardtails get longer reach as the forks sag but the back end obviously doesn’t. This also means the head angle steepena under sag and the seat tube angle also gets steeped.
With a full suss you get sag at both ends so the changes between unsagged and sagged are generally less extreme.
I ride a Santa Cruz Bantam, (medium) and the reach is a fraction under 400mm; will I die?
The diagonal distance between the BB and the top of the head tube is the major factor in how big a bike feels in my experience.
This is what we used to class as reach on trials bikes as you're standing all the time, sounds like it's the stack height I need to consider as well.
I'm 5,9 and ride a small firebird 29 435 reach iirc