Reach cannot be adjusted.

Given you hold onto the handlebars rather than the head tube, surely stem length adjusts the effective reach?

On the subject of Spesh and Cotic not using the more typical S, M, L, XL sizing nomenclature, my favourite sizing chart was the previous Geometron one:

Long
Longer
Longest
Extra-longest
XX Longest

😀

My bike has 440 reach which is too short according to this. In reality it’s fine and very comfortable.

Stack hight is often overlooked. Really frustrating that bike manufacturers to often spec very short headtubes, and then cut the steerer tube with almost no room for spacers. What good does 520mm reach do if you have to hunch over like it’s s triathlon bike? I wonder how their testriders are built.

Definitely read the manufacturers size guidance! I’m 6ft but ride a medium Canyon Lux Trail.

It fits me perfectly and there is no way I thought I’d ever ride a medium!

Interestingly the most critical review of the Lux trail was from a 5ft 10″ guy riding a large frame size…

Some key bits missing from this article

Stack.

Generally too little on large and xl bikes, hence stacks of spacers and riser bars

Reach, useful to know when out of the saddle, less so for fitting for in saddle use.

I agree with the above on stack.. Why on L and above is it always so little?

You can pop a load of spacers on the fork, but it looks gash.

And reduces your effective reach too.

Ritchie Rude laughs in the face of your recommendations.

And then goes on to win every race he enters on a bike ‘too small’ for him.

Ritchie Rude laughs in the face of your recommendations.

And then goes on to win every race he enters on a bike ‘too small’ for him.

A lot of the EWS racers ride ‘too small’ bikes, however they’re good enough that they don’t need the straight line stability that a bigger bike gives them and they’d rather be able to make time up in the corners. Vastly different skill levels 😁

Effective top tube is an important measurement too, which is affected by both reach and seat angle. 2 bikes with 30mm different reach measurements came have identical ETT thanks to much steeper seat angles.

I guess if we’re honest with ourselves, you could ride anything on anything, and ultimately the arbiter of whether your bike geometry is any good is you yourself. So this article could be distilled down to “run what you like” 🙂

But nonetheless, it’s useful to have some ballpark guidance. And really, if your existing bike has short reach and a steep headtube angle, and it’s OK for you, then what the heck, go and ride it and more power to your elbow.

But if you’re in the enviable position of buying a new bike, there’s no real drawback to getting something longer, lower, slacker. I know people talk about bikes making trails dull, but as a noob I’ll take maybe-slightly-duller over will-send-you-otb-like-a-flash-on-anything-steep.

You can pop a load of spacers on the fork, but it looks gash.

And reduces your effective reach too.

This is an underappreciated detail. If you have to put 4″ of spacers under the stem, the effective reach will be much shorter.

Stanton have got the reach wrong on most of their HT’s then. Lots of reach is good for stability but there’s more to riding for me than just speed in a straight line. More than happy with 440 reach at 5ft 9” and I’m all arms.

But if you’re in the enviable position of buying a new bike, there’s no real drawback to getting something longer, lower, slacker. I know people talk about bikes making trails dull, but as a noob I’ll take maybe-slightly-duller over will-send-you-otb-like-a-flash-on-anything-steep.

Bit of hyperbole there. We all rode shorter and steeper bikes until relatively recently. Despite being told that long, low and slack 29ers are great my fastest times on some local segments are from years ago on a 26” wheeled Bfe. Never went OTB on it despite being relatively new to MTB at the time and rode some steep and silly stuff on it.

The advice in the article is great but test riding is key. Not everyone wants long, low, slack. It has definite advantages for sure but it’s got silly with some bikes.

Length of stem is irrelevant to reach. In terms of handling characteristics the reach measurement should be looked at as a percentage of the bb to bars measurement, in that everything else being equal, a bike with 480mm reach and a 70mm stem will handle very differently to one with 500mm reach and 50mm stem.

It’s not so much “irrelevant” it’s just that unless you are running a slammed, inline stem the reach figure given on the geo charts is, at best, only an indicator of the assembled bike’s layout. real life “reach”, lets call it horizontal distance from your grip to a perpendicular point inline with the BB is affected by a number of components (bar/stem/fork and of course the frame)…

Geometry charts are lovely, but then you fit some parts, twiddle suspension and hoist your bulk on there and those variables utterly skew all of those numbers, plus every rider will prioritize different aspects if how the bike rides. Treating a manufacturers/journalists spreadsheets like gospel, especially as they’ve added a few chapters to that gospel lately, is kind of laughable, the “rules” are being rewritten on the fly. Which is fine, but it doesn’t make older bikes suddenly unrideable.

So Yes I should more than likely be on a longer frame, I don’t have a spare £1.5k or the inclination to make that happen any time soon. I mostly notice my frame’s short reach on climbs, and I can handle the compromise, it’s not bonkers to adjust contact points in the short to mid term just to try and address how the bike behaves a bit, I doubt I am unique in this…

I think that bikes have actually got bigger over the years, and not just the wheel size and handle bar width.

I used to happily ride medium frames but now feel I need a large.

Recommended reach numbers for rider height:

Under 5ft 2in (157cm) = 410mm to 450mm
5ft 2in to 5ft 6in (157cm to 167cm) = 430mm to 470mm
5ft 6in to 5ft 10in (167cm to 178cm) = 450mm to 490mm
5ft 10in to 6ft 2in (178cm to 188cm) = 470mm to 510mm
6ft 2in or above (188cm+) = 490mm to 530mm

These number do seem quite a bit off to me. Of course, they don’t include stack, but assuming a somewhat common stack for each frame reach, the reach suggested here for short riders is way too long, and for tall riders, a bit too short.

This is generally the problem with frame sizing: the small, and especially the XS, are too long and too tall (stack), the XL is too low and the XXL is too short and too low.

Back to the reach chart:
There is no way a 5’2” rider can get a good fit on a bike with a 450mm reach. There simply aren’t short enough stems to get the grips in a close enough position for true, controlled riding, where the rider manipulates the bike, pushing and pulling the front up and down and sideways.

Stretching high and forward (too tall and too long bike fit), like a baseball player catching a high ball, is a position that makes it virtually impossible to either push or pull on the bars.
If you are a M or L size rider, you can try this out by grabbing a XXL from a friend.

This is compounded when we consider stack. To a certain degree, a long reach can be compensated with a low stack. Except, in realty, small and XS bikes have high stack (relative to seat height), so this is not an option here.

When my daughter was around 5’2”, her bike had a 390mm reach. Combined with a fairly tall stack, it gave an upright fit that allowed her great bike control.
The longest reach I would even consider for someone 5’2” tall would be 410, and even then I would want to carefully fit it before committing to buying.

On the other end of the chart, 490mm reach is pretty short for a 6’2” rider, let alone one taller than that.
Again, 490mm reach might work if the stack was high, and combined with high rise bars, but in reality the stack is low for on these biggest sizes.

Lee McCormack (Leelikesbikes.com), one of the best coaches around, has developed a fit system based on rider control. My experience as a bike fitter is that it ends up a bit on the small side of comfort for most people, but even if you go up a bit from his suggestion, you still end up far shorter (for short people) than the chart above suggests. Short riders need to really watch that their reach is not too long.

Here are two videos showing and explaining this: