EWS Rider Bike Size and Height Chart

PB Forum :: All Mountain, Enduro & Cross-Country
EWS Rider Bike Size and Height Chart
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Posted: Sep 29, 2020 at 7:45 Quote
This is data from the last year or so worth of EWS bike checks. I only included data where the rider height and bike info was readily available and looked reliable.

Very few riders are running really "progressive" geo or upsizing. A few are downsizing significantly. Most are running "new normal".

To recap something I posted in the comments, this is my current best understanding:

A long front-center (which is influenced by the head tube angle as well as reach) can decrease cornering performance if not accompanied by a lengthened rear end. You'll note some riders who are downsizing significantly are on bikes with short chainstays (Firebird, SB150).

A longer reach can provide more stability and allow the rider to relax and survive down the fall line, very useful for Enduro. However, top-level EWS riders are riding more and more like DH riders, where they pump and work every section of track. DH bikes are kinda short (in reach, not wheelbase) compared to 2020 Enduro bikes, and I suspect one reason pros downsize is their desire to backside features for speed, riding actively and aggressively.

EWS courses often involve very tight switchbacks, moreso than the modern purpose-built MTB trails most consumers ride.

Riders are also conservative, avoiding substantial change if their current setup feels good. At the same time, they generally look for any advantage. Each rider has a different balance of conservatism desire to take risks for possible gain. This will be reflected in their choices.


For the amateur Enduro racer or trail rider, this is interesting data, but perhaps not to be taken too seriously. My own personal interpretation is that one certainly can be fast on a bike that's not super long, and I suspect it will reward a very active, pumping and pushing style that I am far from mastering, but enjoy working on. I might be giving up a little stability, but I'm compensating with longer chainstays (440) and slacker HTA (64.5), to keep the bike reasonably compact (465 reach, 40mm stem) for my 181cm height.

Posted: Sep 29, 2020 at 7:58 Quote
Pros can ride fast without needing a huge reach and wheelbase to feel safe and give them confidence, as such they can benefit from the snappier handling and lighter weight of a normal size frame.

Posted: Sep 29, 2020 at 8:32 Quote
NGL, this list makes me wish I had downsized my frame. I'm 5'11 on a large Firebird 29, which means I have a couple cm's longer reach than a lot of these riders. would explain why I switched to higher rise bars and still feel like I need a shorter stem. but I'm not a pro, and I appreciate the stability on downhills.

Posted: Sep 29, 2020 at 8:49 Quote
I always watch the interviews and follow a ton of pro riders. Seems like a majority of riders prefer the shorter set ups.

I always thought the 443 reach on my HTLT was perfect for me(5'10").

Posted: Sep 29, 2020 at 10:07 Quote
Thanks for this. I'm shopping for an enduro bike to race next season and this is really informative.

Posted: Sep 29, 2020 at 10:21 Quote
Great info! Just getting into trail/enduro riding after a 13 year hiatus (post injury from my street/park/dj riding youth) and looking to upgrade from the bike I picked up at the beginning of the year. At 185cm I straddle large and extra large sizes and living somewhere without the option to demo bikes has made choosing a size stressful. I figured I should be looking for around ~470mm reach, about where pros my size in the chart are, but perhaps something a bit longer will offer some greater safety factor when the going gets steep?

Currently on very undersized 434mm reach 5yo medium frame and have been having a blast on all but the double black trails. I do like the tossability of the shorter bike but I'd also like to get into enduro racing so perhaps a 480-490mm reach with shortish chain stays would offer then best compromise? The trails here can be pretty steep tech with plenty of rock rolls and chunk, and lift access is non-existent so climbing is a high priority.

Posted: Sep 29, 2020 at 19:15 Quote
Love this data - shows a clear disconnect between pros and PB review team (plus many commenters).

I feel it basically comes down to most average riders not riding difficult tech anymore.

Marry up a long bike with a groomed bike park with 'catch berms' and straight line trails, and you've got a recipe for an average rider to feel like a hero shralping berms, floating tabletops and transferring lines without ever having to snap corners or aggressively move the small bike into difficult low speed lines.

Posted: Sep 30, 2020 at 3:00 Quote
This is really interesting. Thanks!

Posted: Sep 30, 2020 at 3:04 Quote
Hey nice data ,

Here it is in a scatter plot with outliers highlighted ( Eddie, Jack and Richie shorter bikes vs G. Callaghan and M Simmonds longer)


I think there are two key variables for Enduro/DH bike sizing,

1. Bike Fit (from Lee McKormacks Dialled Geo book) defined as the RAD or distance between centre of BB and Handlebar Grips which should match distance between your hand and feet when your hands are at your side standing.
- His logic is that too long and key muscles switch off in your back and glutes to protect your spine so pumping and generating speed is difficult. Most bikes fall into the too long category these days, personally I should be 805mm RAD and my bikes varied from 805mm to 830mm...I brought my bikes back to 805mm with anglesets, shorter stems and feels good! I also created a small model to calculate all of my prior bikes RAD to understand why some bikes felt great and others were unwieldy...turns out up until the lower slacker longer thing in 2015, my bikes were bang on 805mm, then sizing up to L pushed up to 830mm which gave a ride experience best described as a point and shoot passenger!

2. Bike balance; Here I developed an idea around an ideal FC:RC based on personal experience and analysis of the winningest bikes in DH history. First off, I looked at Sam Hill's bikes as he is the cornering genius...what kind of bike geo does he go for? Turns out ca. 1.7 FC:RC same as R. Rude and B.Atkinson --> what are they known for? Cornering ability!! I also did this for G.Minaar, S.Peat, A.Gwin, N.Vouilloz, G.Atherton and R.Atherton...I plottted their success rates per season from Roots and Rain vs bike Geo, looks like there is a correlation between % from Fastest Time of the Day (FtD) and FC_RC ratio, but it is quite weak --> % From FtD is lowest at around 1.75 FC:RC. It increases if you go lower or higher than this value.

I then modelled the FC:RC of prior bikes I owned to understand why specific bikes were total weapons around corners/ difficult to manual vs poppy and fun but sketchy in corners...turns out the 2015 bikes were awesome at cornering with a FC:RC around 1.70 but tricky in the steeps, >2015 longer FC made it harder to weight the front and turned the bike into a point and shoot type affair at >1.8,1.9 FC:RC. Ive since gone back to a shorter FC and lower FC:RC of 1.75 and its a nice balance between manuallable/pop and cornering front wheel balance and traction

So there you go! My "bro science" with some research --> calculate your RAD, Match it up to your bike to get the correct FiT, then make sure you can get a reasonable FC:RC ratio that fits your style, personally I like how 1.75 corners, but if you just ride 45 deg steeps and like to manual everything, go for a >1.8 FC:RC.

Data


Posted: Sep 30, 2020 at 4:58 Quote
While I totally agree with the idea of having a balanced bike, it's a bit of a leap to assume that EWS riders are choosing their bike size from an objective data/engineering standpoint. Greg Minnaar who for most of his career felt like he was a bike that's too small even said he thinks that racing on larger bikes had to come in stages; that he couldn't have made the leap directly to the bike he's riding now. Racers (even outside of bicycles) tend to not want to deviate from a successful formula. That's kind of what happened with 29ers in DH and enduro racing. Lots of riders hated them at first.

Posted: Sep 30, 2020 at 18:45 Quote
The optimum size for a race bike also depends on the kind of tracks that are raced on.

You can’t just look at numbers and say it’ll be faster.

As WC tracks got faster and more built up, bikes change to optimize performance in these specific conditions. Go back to lower speed tech and janky line choices in DH racing and you’ll see bikes adapt again.

Posted: Sep 30, 2020 at 23:56 Quote
Linc wrote:
The optimum size for a race bike also depends on the kind of tracks that are raced on.

You can’t just look at numbers and say it’ll be faster.

As WC tracks got faster and more built up, bikes change to optimize performance in these specific conditions. Go back to lower speed tech and janky line choices in DH racing and you’ll see bikes adapt again.

Exactly it's horses for courses, long low and slack isn't the best option everywhere all the time just like F1 doesn't run the same aero, suspension and tyre setups ect every race. Buy what 'you' like that works where 'you' ride.

Posted: Oct 1, 2020 at 2:17 Quote
So I think the main point is, you need a bike that fits you. Longer only works if you have been riding bikes that are too short (seems obvious!) but when people size up randomly thinking longer is better, well its only better if your current bike is too short! The problem is bike fit is an art in itself and most people look at Reach or Stack maybe but where I think Lee McKormack's RAD (Rider Area Distance) measurement is ingenious, is that it is a single measurement that you can map directly from your physiology to the bike independent of HA, StA, BB height etc.. its literally where your two contact points meet the bike when descending out of the saddle--> feet to pedal and hands to handlebar. If you go too long then you cannot apply appropriate levels of power to pump and generate speed dynamically as your ride position/posture puts your spine in a compromised position/risk of injury --> inhibiting certain muscle groups, same if bike is too short...Imagine doing a deadlift with your back either pronated or over extended and try not to get injured!

"That’s how Sam Hill measures his bike, he gets on any bike, no point telling him any numbers, he just gets a tape measure and measures feet to bars, and if it makes sense, then he’s happy, and away he goes. I do think that’s the only true measurement you can work off." Ali Beckett NP Designer

I really recommend "Dialed The Secret Match of a perfect Mtb setup" by Lee McCormack if you want to dive into this in more detail.
Here is an article for pb he wrote on the subject:
http://https://www.pinkbike.com/news/lee-mccormacks-guide-to-perfect-bike-set-up.html

Whats your RAD? Its easy to measure your bodies RAD (bottom of foot to centre of hand when standing with hands by your side). The problem is how do you know the RAD of a bike? You can measure it if its your own bike, but if you are thinking of buying a bike online you need to calculate via some trigonometry. I have a model that can do this based on Reach, Stack, stem length and spacers under the stem. But failing that here is an approx relationship between Reach and RAD from around 25 bikes I have modelled. Therefore as a starting point you could infer your ballpark Reach from the graph to deliver a certain RAD and fine tune with stem length, spacers, anglesets. Or you could use this equation: y = 0.925x - 305.37 where y = Reach and x = Rad, to calculate your Reach starting point.

e.g I measure my RAD as 805mm (I'm 176cm), this would give --> 0.925*805-305.37 = Reach of ca. 440mm.
Meaning if I bought a bike with a reach of 440mm, I could get it to fit me pretty well with some fine tuning.


So once you have a riding position that fits (which is priority no.1) you can start to think about HA, Wheelbase, CS length, Stack to get a bike that descends well and corners well (combo of stability and front/rear balance/traction).
STACK: For DH/Enduro, a high Stack enables upright position and good vision, ability to descend steep terrain safely, too high and front tyre traction may be an issue in flatter/mellow terrain) --> personally I go high
Handlebar width: Needs to be proportionate to your shoulder width to keep stable and strong position (too wide and your shoulders are super compromised)
HA: Slack enables a longer FC without compromising the bike fit, you can extend the FC whist maintaining a short cockpit (64-65deg for descending biased riding is probably fine for most people)
STa: Steep seat tube angles seems a no brainer as it enables greater power transfer and reduced pressure on lower back
CS: Shorter for more pop, "manuallability" and pump with a more rearward biased weight distribution, at the expense of front wheel traction, Longer for more stability (longer wheelbase), shift weight bias to front slightly, reduce pop, pump and manual ability.
Wheelbase: Longer is more stable, but its where you get the length, just FC or balance FC and RC?
FC:RC: Balance between FC and RC, a ratio that is independent of bike size --> is there a golden ratio? Maybe but everyone is different, style, tracks etc.. Shorter and you get a corner carving, wheels on the ground feel, longer and you get a poppy, point and shoot plough that manuals out of corners if you hit them hard enough. So need to be aware of it but not too hung up on a perfect value. Somewhere between 1.7 and 1.8 seems optimal for the average p50 rider.

So bikefit is not really up for negotiation, the bike either fits you or it doesn't, but picking the remainder of a bikes geo is a compromise, you cant have a 100% perfect bike for all situation, but one that handles the majority of terrain you tend to ride, the majority of the time.

Posted: Oct 1, 2020 at 4:01 Quote
Thing with the RAD measurement is it doesn't tell the whole story, you could have a super short reach and high stack or a super long reach and low stack both giving the same RAD measurement but are polar opposites in terms of the bikes actual geometry. So yea maybe it tells you if it fits but it doesn't tell you at all how the bike will behave. Additionally you find with the new crop of bikes with steep seat angles the bike actually feels smaller and more comfortable and upright when seated so you can get away with a longer reach for standing whilst having better geo when sitting.

Posted: Oct 1, 2020 at 7:10 Quote
Danzzz88 wrote:

Exactly it's horses for courses, long low and slack isn't the best option everywhere all the time just like F1 doesn't run the same aero, suspension and tyre setups ect every race. Buy what 'you' like that works where 'you' ride.

Speaking of F1 examples... it's kind of like how F1 uses 13" wheels still. It might be tempting to look at an F1 car and think that since they use 13" wheels with high profile tires that must be better and I should try to replicate that on my sports car.

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