The misunderstood reach and bike sizing

[Sherman]

This was originally intended as a reply to another post, but I decided to post a new topic as this is a thing I keep bumping into all the time here. Which is 'reach equals bike size'.

Reach does mean how far you have to reach for handlebars when seated. Reach is the distance between bottom bracket and head tube. There are many other variables when sizing a bike.

I have two bikes (Turbo Levo 2017 and Pole Evolink 158), the difference in reach is an extreme 75mm (460mm vs 535mm). But I sit more upright on the Pole due to much steeper seat tube. The distance from the saddle to handlebars is longer on the Levo. Yes, the stem on the Levo is quite a bit longer (60mm vs 35mm), but even with same length stems the difference from saddle to handlebars would be about 15mm apart each other.

Bike sizing has not changed, size M is still a size M even with the new school geometry. You have to look at the complete package, test ride and figure out your intended usage when choosing a bike. And test ride again.

Further reading:
Enduro magazine: 'The Great Confusion: Why geometry tables don’t help'
Transition bikes: Modern Mountain Bike Geometry Defined

 

[Pukmeister]

I just went by the makers guidelines and the store manager confirmed this at a glance. Luckily for me it seems we were spot on.

 

[ggx]

Usually there are lots off concernings about right sizing choices .
Less usual but I´de like to see/read/discuss about how same bike in diferente size beave or compare with other models !?

 

[brash]

Front centre is another measurement few understand.

Specialized with their stumpy Evo, new enduro and demo have moved away from the traditional S-xl sizes and now have s2-5 depending on the model. It’s basically a reach meaurement. Some may like a smaller more nimble feel and go for the shorter frame while others may prefer the neutral position a longer reach gives and a longer wheelbase and go up a size.

Geometron/Nicholai & pole have also got it figured out.

I ride a S3 stumpjumper Evo as a training bike, which in geometry talk, is longer, lower and slacker (you read that right) than my 2018 XL s-works demo race bike.

 

[FlyingKiwi]

Reach is from standing and not seated. Effective top tube is considered when assessing how far you may reach when seated, the Reach dimension is used in a consideration of how far you may reach from a standing/ riding position eg. the more fun and, outside of x-country, the most important dimension when contemplating bike size and rider position when up off the saddle pointing the bike down.

 

[FlyingKiwi]

....in saying that even more important is probably the Reach-around!

 

[Rosemount]

Lee McCormack's Guide to Bike Set-Up - Pinkbike

Lee McCormack tells you what he thinks the most important measurement is when setting up your bike.

www.pinkbike.com

 

[Gary]

Reach does mean how far you have to reach for handlebars when seated

No it doesn't...

and the rest of your post is complete nonsense too.

Your Pole Evolink is stupidly long (in comparison to your Levo)

Bike sizing has not changed, size M is still a size M even with the new school geometry.

Yes it has. Massively. Especially over the last 4 years on trail/enduro bikes

You can't even buy a new 2021 150mm FS bike with a wheelbase/reach which would have been considered normal on a small sized bike in 2015 anymore. The industry has effectively sized out bikes for small riders across the board telling us all we need longer bikes. We don't! Longer bikes have just as many disadvantages as advantages.

 

[Zimmerframe]

When small was smaller ...... and fun ...

 

[Gary]

Exactly Zim

RYFB MOAR

 

[STATO]

Reach is fixed, you cant (easilly) change it. Thats why its used as a comparison, of course you should look at other numbers but as a starting point its better than effective top tube which is nonsense on anything but an xc or road bike.

Stem, bar sweep, seatpost (layback or straight), saddle design, where your saddle is clamped on the rails, etc. are all adjustable by the user to put them in the position they want to be. So yes if you want the same saddle-bar distance you can adjust these, heck you can make a size small feel the same when seated as an XL with a long enough stem and seatpost.

 

[Gary]

and here we go again. someone else who doesn't understand what they're talking about.
Effective top tube and reach are BOTH virtual measurements.
Neither one is "better" than the other.
BOTH will give a fixed length when measured correctly. being virtual BOTH are a little awkward to actually measure. But neither are any use at all on their own.

Control contact point (bars, grips, levers, stem) position affects handling.
Saddle position (height, fore/aft, angle) affects pedalling efficiency/comfort.

Luckily the human body has handy joints all over it and humans are adaptable and (some) even have the capability to make free choice and think for themselves.

 

[stiv674]

My current 2018 size medium Focus has a reach of 430mm, it seems pretty much right for me, but when I put my measurements in to a bike manufacturers sizing calculator, it always seems to recommend a bike with a much longer reach, 450 plus... I guess my bike is too small for me... ?

 

[Gary]

all Eebs ride better with slightly less length

 

[Zimmerframe]

all Eebs ride better with slightly less length

That's what @BAMBAMODA tells all the ladies....

 

[Gary]

Fuck it. We might as well embrace technology in all physical pursuits

 

[Swissrider]

Whatever way you measure it, if reach is too short, one feels cramped. It can be alleviated by using a longer stem and sliding the saddle right back but that can alter the handling dramatically. If reach is too long, one feels too stretched out with too much weight on hands and wrists. If reach is right for then you’ll feel neither too cramped or too stretched. Once you’ve found the sweet spot, measure the angles and lengths between the middle of the handlebars and the middle of saddle, between the middle of saddle and bottom bracket, and bottom bracket to middle of handlebars. You should be able to compare these with drawings of bike geometry or an actual bike to give you a good starting point. If you have the same figures on a new bike to one that already suited you, the new one will fit your body, and don’t be afraid to experiment. I used to ride small, but am now happier on medium as I’ve got older and less brave I prefer the stability that comes with a larger size, compared to the throwability of a smaller size.

 

[Madmountainman]

In the main, for your average height rider, you can just try different bikes out for size. However, if you're like me and around 1.98m, understanding geometry becomes fairly important.
Take the Kenevo. On paper it looks like it's got a long reach and wheelbase, ideally suited for a taller rider. However, the raked out fork angle combined with the steep seat angle serve to create a very cramped cockpit when sat. Also, the difference between actual and effective seat angles are very close so, as your seat goes higher it doesn't travel much further back to create space. The low Stack only serves to increase weight over the bar, unbalancing the bike for taller riders.
Now look at the Bullit. The actual seat angle is fairly laid back, despite having a reasonably steep effective angle, which increases the reach when sat, ideal for us taller riders. The really high Stack means that a taller rider remains centrally located over the bike and helps to minimise that 'over the bars' feeling we all hate when the going gets steep. The Bullit wins over the Kenevo again here, as the Front Centre is just that bit longer too.
If you understand Geometry, you'll know that the ETT, combined with the SA/HA, Reach and Stack all play a joint role in how a bike feels. All riders will notice these differences to varying extents, but it becomes more noticeable the further from average, at both ends of the scale, you are. If you only look at one or two geometry figures, you'll stand a higher chance of getting a bike that won't be the best for your needs. If you understand that the combined figures all affect each other, you'll learn which bike will fit you best. If you're around average, you can combine this info with lots of test rides to find a bike that feels right for you, but test rides on S and XL/XXL bikes are very few and far between, which is why a good understanding of geometry is useful. Looking at the RAD measurement, linked in an earlier reply, that basically sums up what i've said and is my go-to measurement to confirm what i've already worked out from the listed geometry figures on any bike.

 

[BBear]

I just thought reach was how far you have to lean forwards to hold the handlebars. I don’t see how any bike can have a definitive ‘reach’ measurement because we’re all different and there are other variables as well?

 

[Madmountainman]

I just thought reach was how far you have to lean forwards to hold the handlebars. I don’t see how any bike can have a definitive ‘reach’ measurement because we’re all different and there are other variables as well?

Reach is only one part of the equation. Take a vertical line up from the bottom bracket and a horizontal line from the headset. Where these two lines intersect is your reach - when a measurement is taken from this point to the headset.
However, take two bikes - one with a 64 degree SA and one with a 68 degree and each bike will feel completely different when sat. That's why you also need to consider the ETT when fitting a bike to yourself. When stood, both bikes will feel very similar, as long as they have similar stack, but if there's a few centimetres of difference, you'll feel like you've got more body weight over the front wheel. The RAD is useful for getting this bit right, but even if you had the same RAD for a Bullit and a Kenevo, the Kenevo would still feel cramped, by comparison, when sat. I'm a fairly even build, neither too long or short in legs, arms and torso, but find the SC's geo suits me best. If you're shorter in the torso and/or arms, you may find the Spesh a better fit.

 

[Rosemount]

ETT , RAD = whaaa ?

 

[Madmountainman]

ETT , RAD = whaaa ?

Try reading the whole of this post. There's a link to Lee McCormack's approach to bike fit, which is RAD.
ETT? I really shouldn't have to be spoon feeding information like this. Look at any manufacturers geometry guide and you'll see what ETT is. Not having access to bikes in XL/XXL sizes makes it essential for me to understand a bike's geometry in order to know if it'll fit. It's looking highly likely i'm going to order a new Bullit - although it may be a year before it materialises - and that's a lot of money to spend on something you can't try out for size. Fortunately, I took the time to understand geometry, have had a test day on an XXL Heckler and have my current bikes to base a reasonable comparison on. Since reading about Lee McCormack's RAD i've measured my bikes, of which both were set up with my understanding of standard geometry and the RAD equation is pretty spot on.
Still struggling? Ride your bike and see how it feels? If it feels like you're falling over the handlebars or overloading and pushing the front end, when going down the steep stuff, you'll need to look at your Stack and Reach. Reach could be longer, or stay the same if you had a higher Stack. Alternatively, if you feel you're falling over the bars going down steeper stuff, but feel it's a stretch to the bars, just go for a higher Stack. Another work around for Stack is to fit a higher rise bar or stem. 'Over the bars' is just one of the ways that 'feel' on a bike affects your ride. There are loads of other permutations, but that's one of the most common and easily felt. Other factors also play into the over the bars feeling, such as wheelbase, head angle and fork rake/offset, but they're more for fine tuning your ride so i've tried to keep it simple by focusing on the Reach and Stack, with a little mention to stem length and bar height. I haven't even mentioned the opposite of 'over the bars', as that's just another can of worms to add to the confusion. ?
The more you ride different bikes with differing geometry, the better your understanding of how that bike's geometry affects the feel. If you're happy with your ride, don't worry about it, just get out and ride. If you're not happy, put some time and effort in to understand geometry and you'll likely find your own solution.

 

[Rosemount]

I have my bike set up Lee Mc Cormack style .
Measurement from the bottom bracket to the grips in proportion to my body .
The bike shop has a Rip Row . I have watched a lot of Video of Lee coaching .

I read your post more than once it still didn`t explain RAD ...
You only needed to spell out RAD once then use the acronym and folks would understand .