[Closed] Are modern bikes too long?

Yes, but no. It all depends on how (and what) you like to ride.

I saw the same video and found it really interesting. I'm no expert but have fad similar thoughts.

I'm not sure my needs match theirs as I'm not a dirt jumping ex-bmxer but, I'm also (despite my best daydreams) I'm not a super radgnar enduro racer. As much as I love the down hills, the vast majority of my time is either up, or along. So much more of my time on a mountain bike is sat down and pedalling compared to what the current fashions would have you think.

The modern long bikes are designed for maximum fun going really rather fast downhill, if you don't do a lot of that maybe they are less than ideal.

I rode a friend's old steep head angled shorter full suss the other day down garburn pass. It climbed brilliantly but tbh it was a bit scary going down steep techy stuff and I was slow. You pays your money etc

I think I saw this video on it first.

No, it's all about the right tool for the job. Being 6'5" I feel like bikes are only just being made in a size that really fit me. When I look at pictures of me riding a bike from a few years ago I look like I'm riding a children's bike.

That said, I have a 4x bike for messing around on that must have a reach of low 400's, it feels great fun but very twitchy. My hardtail is 510 reach and my full sus is 528mm. They all arguably fit me but vary in size massively and ride very differently.

But when it comes to fitting bikes in my car/shed/garage/workshop, yes they're too long!

I'm 5ft 9in and Morden reach means I can ride a small and have 180 dropper. Winner

yes they are too long for reach. some small bikes have a reach that is too long for me.

Not all bikes no. The option of longer reaches is welcome for many, and shorter are still offered for those that like more moderate reach figures. Don’t really see a problem.

I think the discussion isn't one of "should they stop making long bikes" but more a case of selecting bikes by considered/informed choice rather than following fashion.

It depends who you are and what you want. MTB's were shaped like 1980's road bikes for 20 years which is absurd and larger sizes were well overdue.

I'm 6'2" and my current bike is the first I've ever had that feels like it really fits. I've never ridden anything that climbs or descends so well and it's a comfortable place to sit all day. So yes it's probably too long for most people but for me it's a godsend.

I did however grow up riding BMX, hitting ramps and jumps and I find this kind of riding much harder on a big bike. For most people in most scenarios it's a non-issue. The combination of raked out front end and long chainstays makes it an absolute pig for lifting the front wheel and popping trannys.

I want hardtail or shorter trail bike for fun rides full of jumps and wheelies before I get so old I completely forget how to do it.

(current reach is 520mm, wheelbase is 1328, head angle 62)

As much as I love the down hills, the vast majority of my time is either up, or along. So much more of my time on a mountain bike is sat down and pedalling compared to what the current fashions would have you think.

Yep, that is where I spend most of my time. I am on the seat almost all the time other than some standed climbing and some trickier bits. That is the terrain where I live so I therefore have the bike that suits it which is a short bike with 68 HTA.

There's a couple of taller guys commenting here that are saying bigger bikes are better. I'd be interested to know what "bigger" actually means. Are they better because they're bigger than bikes of old or because they're RAD++?

I'm tempted to set up a couple of steps in the garage and test my RAD.

Depends on your body dimensions. Having long legs and torso but normal length arms is a problem for reach. I've rarely had a bike that fits me, and have had to resort on one bike to fit a bmx Stem and single wall supercross bars to get the stack height I needed.

What do you mean by longer and to what effect, my current bike, which is a transition patrol in medium has a reach of 450mm, and a top tube length of 583mm, my 2003 full susser had a top tube length of 580, so not exactly hugely different in terms of the length from me in the saddle to the handlebars, my stem is 35mm long now, back then it would probably have been 90mm!

Folk get carried away with longer, reach for me is a dimension that gives me info on how i will be positioned when the saddle is down and i'm out of it, going uphill, reach means nothing, as i am not in the attack position, i actually find my patrol feels shorter than my ebike, which has a 430mm reach, again this is down to so many other aspects being in place, wheelbase has of course got longer, but we're no longer running 26ers, so not dramatically in terms of keeping the same geo with larger diameter wheels.

Has anyone commenting here checked their RAD yet? I shall check later and report back.

Maybe-ish? (I'm 6ft)

I demoed a bike with a 500mm reach and whilst it was brilliantly bonkers at just rolling down bumpy stuff without thought, it wasn't something I'd want to actually ride. You just had no direct control over it. Lifting the front wheel was only really possible if you preloaded it then tried HARD to manual. You couldnt just unweight it.

But then 10 years ago 475mm was impossible to find outside of XL frames and 450mm is way too short. So for me my ideal seems to be at the long end of mainstream but not in the realms of Bird/Geometron or the other out-there geometries.

I think the range of sizes used to be too narrow and too skewed towards shorter riders (ignoring excessively long seat tubes). And now it’s skewed towards taller riders.

I’m about 5’11” with long limbs (6’2” armspan) and very happy at 455mm reach on both bikes. I think the wheelbases are 1230mm on the Levo and 1185mm on my hardtail.

I think modern bike sizing is good for racing or tall riders. Not so good for shorter riders or anyone preferring to mess about rather than go flat out. Ans it’s no good saying “just ride an older bike” because the trend in head angles, seat angles etc is good!

If you’re 5’7” or under, especially with a shorter torso and/or arms, and wanting fun rather than fast, I’m not sure what you’re meant to buy?

I quite like the newer but not too extreme geometry. I’m 5ft 9” yet have short legs at 29” and arms like a gibbon. So longer reach and shorter seat tube is great. Historically I’ve ridden hardtails the most and think something with around a 66dg HA and a 130mm fork is the sweet spot for me.

It’s interesting alright, by his rough figures I should be on a 470mm bike. Now that’s a lot, lot smaller than I’m on (yes I might have gone too long..). So I’m 189 cm 6’2 in old money, I don’t Chuck the bike about like these guys do they’re much more poppy jumpy hoppy...I’m more trundle, survive, jump if really necessary!! So the smaller bikes might be more suitable for them. I think if I’m not sure comparing me to Richie Rude would be overly helpful...in the same way comparing my bike fit to Tom Boonen’s would be?

Ok....did the marker on the wall thing...got 89.5cm....I’m an ape, handy for boxing a nightmare for archery kit...my bikes a xl and is 90cm from bb to bar (35cm stem) but it’s also 60mm longer than the calculations say height x2.5....🤦🏻‍♂️😂😂😂

Saw the RAD sizing idea a while ago. I worked it out and it suggests a 500mm reach. My mountain bikes are mostly around that number, either slightly longer or shorter, not far out. But I still think reach is a byproduct of other measurements and angles that matter more, so isn't the whole story. Sizing by reach alone is a mistake.

I think more important if they are too long or not, is that today you have options.
Look at Bird, a 6ft guy can chose between as much as 3 sizes (stretching it a bit, I know) and select dropper travel accordingly.

Yeah that’s a 35mm stem....not cm...😂😂😂

5'10" on large HD3 and it has a RAD of about 80cm. Trying the bike on some steps and testing that way seems about spot on.

If you’re 5’7” or under, especially with a shorter torso and/or arms, and wanting fun rather than fast, I’m not sure what you’re meant to buy?

I'm 5'7" with slightly short legs (29") and normal arms, usually puts me around the crossover between a small and medium frame.

Back when dropper posts first became normal, around 2010-12, I struggled with finding a bike with enough reach but a short enough seatpost to allow a 125mm dropper to go in. That's no longer an issue but the reach figures are increasing massively. I can find manufacturers recommending me to have a bike size with anything from 420 to 480mm reach for the same type of bike. I know from my current bikes and ones I have demo'd that anything over the 460 mark pushes me too far forward to be comfortable while seated and anything under 425 leaves me with very little room to manoeuvre around going downhill. Anything between 430-460 seems to be my sweetspot, shorter for XC and trail with Enduro up near the top.

Watched the video, didn’t realise it was Lee McCormack inspiring this thread - I’ve been following his stuff since buying a copy of Mastering Mountain Biking Skills in 2009!

“I’m 5’7″ with slightly short legs (29″) and normal arms”

You might not realise it but having short legs means you can ride a longer reach bike - I’m 3.5” taller than you but my legs are 4.5” longer, so my torso is shorter. It’s your torso length that determines the reach you need - arms bend so longer arms mostly just give you more tolerance of a wider range of reaches.

I think really long bikes are a specialist thing for sure, I've always liked a longer bike but that's because I like riding long-bike-stuff, recommending the same for everyone doesn't make sense...

But equally, I have a Solarismax which while not massively long at just under 1200mm is a hardtail with more wheelbase and more reach than a long travel enduro bike had just a few years ago (it's a medium but it's longer and reacher than my size large Remedy 29, which won its last EWS overall in 2015). That's a massive change over just a few years, but, it's not made it into a compromised #enduro bike, it's still a very good xc bike and mile muncher that's also aquired a ton of dh and technical ability. It climbs better than my old 26er Soul... I don't necessarily want a longer one but there's never been a second I wish it were shorter.

But basically it feels like for a long time, there's not been any need to ask about "too long" because essentially everything ought to have been longer, so the right answer was always "longer". Now there's probably a lot more bikes getting past that point where "longer" is a thing to choose rather than a thing to do automatically.

It's like motorbikes... For decades, literally every motorbike was too bendy. Engines got pretty good, frames didn't. So then for a long, long time every engineer just added more stiffness to every design, it was always the right decision. Til suddenly, it wasn't- Honda made the RC51 and it was the first time anyone had really made a road bike that was just too stiff to work properly. Suddenly the design decision was different. Maybe that's about where we are now, with longer.

Not across the board though- even in motorbikes there were still loads of bikes that needed to be stiffer even as the pointy end got too stiff, and when you look at entry level mountain bikes etc it still feels like basically all of them could have an extra inch in the front centre and be just overall better for it.

A man with admittedly argumentative opinions has had something to say about RAD...

As you can imagine, he's scathing...

I don't necessarily agree with the idea that long bikes descend well but don't climb or pedal so well. My current hardtail climbs better than anything I've ever ridden, the reach is 9cm longer than the Cotic BFe it replaced. Yes it's a long bike in terms of reach but the steep seat angle means it's the same size from saddle to bars but I'm now far more centred on the bike so I don't have a wandering front wheel on steep climbs and I can push the front much more into corners when descending.

Every bike will be compromised is some way, no it doesn't manual as well as the Cotic but then that isn't as easy to manual as my BMX.

I tried the measuring method, my jump bike is spot on, my enduro bike is probs around 15mm "too long".

It is sizing around a very specific movement, I want full available power for that movement on my jump bike, I think it works out, it feels that way on my jump bike.

On my enduro bike, even being on the pumpy, hoppy end of the spectrum, do I need full potential for that specific movement, I don't think I do, am I happy to trade for a bit of stabilty, I think I am.

So is he saying height x 2.5 = reach, or RAD?

Depends on what you are using it for. An all day XC type machine, it's probably not that the reach is too long, but the seat angle is too steep. If you like the ups and especially the downs, no. Consensus seems to be that longer really is better. Bikes that are targeted at bike packing are still pretty short,with a more relaxed seat tube and a steeper head tube. Horses for courses.
What I would say is that the options for a decent all rounder are limited. Not too long, not too steep, not too short or slack.

You could pick the angles you want and then choose from at least two frame sizes, couldn't you?

Depends on what you are using it for.

Well, if its reach it works for me - I'm comfortable withy Spark RC with a calculated number of 452.6, the Sparks reach is 456 with a 90mm Stem. But, my Clockwork Evo has a reach of 476, albeit with a 50mm Stem, and I find that comfy. So taking the Stems into account I have 546 on the XC race and 526 on the Evo play bike, which kind of make sense by accident...?

“ You could pick the angles you want and then choose from at least two frame sizes, couldn’t you?”

No, not if you’re a slightly shorter than average man or about 80% of women - a whole load of brands are now making their smallest size too long in reach for them.

I'm 6"4 with reach of 530 on my full suss, 520 on one hardtail and 480 on another.

The shorter hardtail has 26" wheels in a 27.5" frame. It is harder up hill, downhill and in the Twisties compared to the longer bikes.

I wouldn't buy a MTB with a reach shorter than 520mm by choice any more.

Maybe I just like it, maybe I'm just used to it, probably I've fallen for fashion/ marketing.

Whatever it is if feels great bombing about 😃

So i’m 5.9” tall and live in Essex so definitely not blessed with steep or long hills but i’m very much in favour of the long, low and slack.

Bikes went from a medium commencal meta to a large banshee splitfire to a “medium “ longer geomatron with 500mm reach. I would say that even if I wanted an xc/trail bike I would still want it to be LLS which there are no bikes that fit the bill. Bikes are generally designed around to things, going up hill or down it. The reach measurement does depend on the length of the bike as well as seat tube angle. Why anyone would was a slack seat angle putting the weight over the rear wheel and not in the middle of the wheel is behound me. As soon as you point the bike down a hill the seat is dropped, is out of the way and it’s only the top tube length comes into play of how the bike will handle.

Stem length is another thing to discuss. If you’re riding a corner properly to shouldn’t be turning the bars much but leaning the bike over (again making the stem less of a requirement to man handle the front wheel (think of a tiler on a boat V a steering wheel of a car. A more direct connection to the steering inputs and direction change).

To me a bike should be like a custom suit to make sure it fits your exact fit (like a bike fit for road bikes) but there a only a few frames that truly allows you to adjust it to fit it to you (g1 being the only one or go custom athertons (but it’s custom one fit and not adjustable after it’s been made).

So I did some measuring today. His 2.5*height (180cm) puts my ideal reach at 450mm, or 459mm for ‘RAD+’. Measuring against a wall puts my RAD at 850mm, and comparing to my bikes the Whyte 901 is 870mm and the Cortex is 850mm. Interestingly from the geometry charts the Cortex reach is 465mm and Whyte is 476mm, so the different bar/spacer stack (both have 35mm stems) cause the extra difference.
From this I assume my torso is longer than his assumed proportions, or he assumes longer stem/taller bar than fitted to either bike, as both should be way too long.
Time to try to shorten the Whyte!

By the method of standing up in that position, making a mark on the wall etc, as per the video, if you take 2 people of otherwise identical dimensions but one with arms 10mm longer than the other has, the one with longer arms will have a "RAD" 10mm shorter and fit a smaller bike.

That doesn't make much sense, surely?

Modern geometry is perfect. Until bike companies want to sell more bikes and invent a new geometry.

“ That doesn’t make much sense, surely?”

It does in terms of how you generate power when doing a clean or deadlift.

I read those two PVD articles and I think they, like also the LLB RAD thing, both fail to take into account body proportions. You can’t work out sizing precisely without knowing where a person’s body hinges. If you look at the world of powerlifting or Olympic weightlifting the experts there know how much your joint segment proportions change your movement patterns and your leverages.

I’ve liked going to bigger bikes but I like where I’m at now - which is short in reach for my height compared to the most current trends but makes sense if you analyse my proportions (and consider that I prefer the steering feel of a 50mm stem vs anything shorter).

I’m also running a lot of stack height with fairly tall headtubes and 40mm riser bars - which correlates with my high hip position due to my long legs for my height. And if you look at the RAAD (angle of the RAD) thing that Lee McCormack talks about, that is overlooked - it’s not just about what you’re riding down, it’s about where your body hinges.

“when you look at entry level mountain bikes etc it still feels like basically all of them could have an extra inch in the front centre and be just overall better for it”

I think it’s important to remember that you can increase front centre without increasing reach.

I think there’s been a lot of timidity in increasing front centre through slacker head angles and taller headtubes, it’s been a slow process for years. That’s improved a lot now we see enduro bike with DH bike head angles and trail bikes not far behind. With longer reach we need higher bars, so taller stack helps.

It will be interesting to see what else changes in geometry. I’m expecting actual seat tube angles to steepen to give more consistent seat angles at higher saddles, maybe size specific seat tube angles (steeper on bigger sizes). More short straight seat tubes for huge droppers. Size specific chainstays or adjustable chainstay lengths.

In answer to the OP: Maybe, it depends.

“ You could pick the angles you want and then choose from at least two frame sizes, couldn’t you?”

No, not if you’re a slightly shorter than average man or about 80% of women – a whole load of brands are now making their smallest size too long in reach for them.

I've been wondering about this too: Cotic FlareMax small, is, according to his method, still a bit reachy for me (I ride a medium, as per their sizing table). Might be time to think about culling a few mm with some SQlabs bars, maybe... Or a frame swap.

Are they too long? No, I don’t think so, you can still buy small bikes if you are small, or that’s your thing, but you can also buy big bikes now if you are tall, or that’s your thing.

I know what I like & I’m probably in the realms of ‘normal’ these days.

My thoughts on this are more specific being 6'6"
A longer bike is more stable but i find more stable a bit boring.
I currently ride an xl older stumpjumper evo with a decent sized stem (80mm i think). It's more playfull than the previous bike that had a much longer wheel base.
I find at the min bikes are too short/ small (seat tube), yes i can fit a longer dropper but that leaves loads of seat post above the frame and bing taller means not light so subjecting the seat post and tube to a load of unnessesary force.

It's similar in some ways to the more travel option, i found a more capable bike boring cause i could ride really rough peak trails sat down where previously i'd be up and picking lines.

Reach is not a great way to size a bike; it's one of the few measurements on a bike where the same person could ride a massive range of lengths and still be perfectly comfortable. It is however good for helping decide what a bike will ride like.

As people spend more and more time at man made trails (both formal and informal) reach has got bigger to allow more stability at speed and of course as seat angles get steeper. This is compromising the slower speed / flat handling of course, but that's the trade off.

Reach is an arbitrary measurement from the BB. It makes a difference it you stand up on you pedals all the time. Obviously GNAR gods do - but most of the rest of us use the seat a lot. So if you have a long reach with a 74 degree seat tube, it will be very long. A steep seat tube and it may well feel short when seated ...
I like long shot geo as it fits my body - tall, long body, short legs - and have always found it difficult to get comfortable on a normal geometry frame.
But, like with most marketing, it will go to extremes, and then come back to a moderate position once the fashion is over.
In a few years time we will look at all the Marinos with 62 HA and laugh ....

Oi Bigdean, any chance you could donate me a couple of inches of your legs ?

5ft 5, 27inseam, try that on the Canyon sizing chart,

M levo, reach 435, the reach feels about right (*doddering xc ramble rider), but I do wish the bike was shorter (and lower tt)

Prior to that a Scott espark, m, also reach 435,

Come on ye smaller wheels !!!!

I found those videos interesting but this RAD approach is seriously flawed. Lee seems so focussed on this maximum power lift thing... maybe that would have some validity if you spent every ride trying to impress bystanders with your walking pace, waist-high bunny hops.

I decided to give the RAD measurement a try (I'm about 5'10" with very long arms and legs and a fairly short torso). This means I get a really short RAD measurement for my height... This makes my large Tallboy about 80mm too long for me! If my arms were shorter than "normal" then the RAD method would say the bike is ok! Clearly it would then be too long!

Reach is not a great way to size a bike; it’s one of the few measurements on a bike where the same person could ride a massive range of lengths and still be perfectly comfortable. It is however good for helping decide what a bike will ride like.

If you understand how the other measurements work alongside it, then it's still the primary metric for me.

Alongside chainstay length actually.

Head and seat angle are also important, but can be fudged a bit easier.

Top tube length and front centre are irrelevant to me, as is wheelbase. They are just outputs from getting the other figures right.

Oh, and seat tube length is critical, bit just has to be low enough. Once it's below a certain point it doesn't matter.

Are sizing a bike and telling how it'll ride not kind-of the same thing though?

Yes, at 5ft5 a trail bike is too long for me making it too difficult to left the front wheel off the ground. Can't get my weight in the right place. My trail bike from 2015 is perfect for me. But current geometry is too long.

Lee seems so focussed on this maximum power lift thing… maybe that would have some validity if you spent every ride trying to impress bystanders with your walking pace, waist-high bunny hops.

Yeah that’s true. He seems obsessed about riders generating power without being interested in whether the bike will be fast or not. A longer wheelbase makes a bike more stable and faster through chunder. Even if that is a compromise when doing bunny hops that's going to be a good compromise for most riders.

I don't even think it is a compromise though. I've thought a lot about the mechanics of hopping (used to ride trials) and I'm pretty convinced that a longer reach is a good thing. If you do 'American' style hops, you pull the front wheel up first. You then launch your body weight upwards from a crouched position to the maximum extent you can - usually limited by the length of your arms at full extension. Obviously if you can jump upwards more forcefully in the space available, you can go higher. But another way to get more height is to increase the space available.

Something like this:

(Still taken from this video:

Extra length is even more useful when doing 'static' moves I.e. you're already on the back wheel, balanced. You're generating all your upwards momentum in the reach-space* available.
Which is why trials bikes have been pretty long for years. NB the trials shop Tarty Bikes has used 'reach' meaning BB to bars (AKA 'R.A.D') for probably 15 years. It's not a new concept, although they've updated their website and are now using the industry-standard reach to mean the horizontal distance (a concept that's a bit irrelevant if your bike spends most of its working life with its front wheel in the air).

* Reach-space is my made-up name for this.

TLDR: More reach is a good thing for stability. It's also potentially a good thing for getting a lot of power into your moves.

On paper my bike is undoubtedly too long for me and yet it feels good nearly all the time riding it.I'm 5'7" and my bike has a 490mm reach - far far longer than any of my previous bikes.The same as Chiefgrooveguru-I seem to have relatively long legs so I find I need to stand tall and keep my hips high on the bike to keep my weight centered,rather than lowering/squatting down more and moving my weight backwards-this is very noticeable difference when cornering. The longer reach and higher stack that my bike has helps me maintain what feels like a more centered and balanced position.

People can be built very differently.

A bike sizing system that purported to be truly accurate would need to offer alternatives for different types of riding, and also suggest more fine-grained aspects of geometry, eg ideal chainstay length, head angle/reach options, seat tube angle, crank length(eeeek!) and so on. You can't represent a bike with just one number any more than you can represent a human.

I’m 5’10” if I stand up straight. My bike has a 480mm reach. I’m by no means a dirt jumper or enduro racer, more of a trail trundler. Strava tells me I climb and descend way faster on this bike than any other I owned before (the last bike had a 435mm reach). And it makes me laugh like a kid when I ride it, too. So I reckon fairly long reach (with a steep seat angle) suits me pretty well. Sweeping statements about geometry “bikes are too long” “head angles are too slack” or whatever probably aren’t that helpful except for click bait and forum rage. 😆

Funny isn't it. I've been looking at my old 26 inch blizzard from 15 years ago... i've no idea how i rode the bloody thing for so long. I raced it, went touring on it, rode it 3-4 times a week for years and years... and it just looks like a kid's bike.

I have been looking at this recently too, as I'm looking at a new bike. I will moving from 10yo 26" bikes, so everything is going to feel strange and almost no test bikes seem to be available. At 5' 7" with short legs and a +5" ape index I'm certainly an average build. If I were to use the RAD calculation I would end up on an extra small frame but would then end up ridiculously cramped when riding seated.

Chainstays on the whole are still far too short and should vary with frame size, small bikes shorter, xl longer and everything else in between. Bikes simply aren’t balanced front to back, huge front ends and short rear ends make for some odd handling.

But how long is too short for chainstays? I ride XL size bikes and don't want long chainstays that make it handle like a barge. We spent the first half of the last decade asking for shorter chainstays on 29ers, and I stand by that. No need to 'balance' the front and rear just because the front has gotten longer.

I've got one bike now with adjustable chainstays. Tried the long setting and all it did was take the fun out of the handling, make it more difficult/slower to turn, and harder to manual. Don't really see much need to vary the length by size but have another bike where it does, longest being a rather short 430, perfect, no odd handling. Both bikes 510-520 reach.

Decently steep seat tube angles are important so short stays don't feel like you're too far back over the axle or cause the front to lift climbing.

Bikerumor have something on this…

https://bikerumor.com/2021/03/19/aasq-110-six-mountain-bike-frame-mfgs-discuss-proportional-length-chainstays/

430 on the XL Smuggler I use for XC, 455 on the large G1 for gnar.

G1 feels more balanced and can climb steeper gradients, horizontal seat offset from the BB is the same on both bikes (virtual seat tube angle). Going down, G1 is faster through the turns, all the time. G1 has a 82mm longer wheelbase (1242 vs 1324).

But how long is too short for chainstays?

430mm

😉

It's clearly personal innit - and comes down to handling priorities.

I ride bikes with 460mm and 475mm reach - and chainstays of 435mm, 445mm and 450mm.

The 460 reach/450mm CS bike is the best-balanced and most-intuitive handling for me.

Yes, a steeper seat angle would stop the 435mm rear one lifting at the front on climbs, but it would still lack have the same planted feel and stability on rough or steep trails. I buzz my bum most on that one too as I need to get my weight back more.

I used to have Konas with long fronts and short rears, and they were more playful, nippy and easier to manual - but felt like they got out of their depth a bit easier.

Adjustable chainstays do seem to be the answer here.

I always wanted the shortest chain stays possible but bought a used frame with sliding dropouts and the shortest I can get them is 450mm.
Turns out it climbs better than shorter chain stay bikes I have had and the handling is great but they seem to be very much against the latest trend in chain stay length but then my head angle is only 68 degrees so the whole bike is clearly a death trap.

Watched both videos, they speak with confidence about what "suits them", also read the link and this bit caught my attention about RAD and its founder/author:

He also works with a ton of novice riders that are looking for easy confidence.

RAD or Reach or any other new way of measuring bikes doesn't account that these are personal preferences. As with a few other posters on this thread, I've just gone from a bike which was "short" to a new "LLS" and am loving it, got an extra 49mm in reach, 10mm in the chainstay with a wheelbase increase of 84mm and could not be happier, the bike does exactly what I purchased it for which is enable me to go fast downhill, I know it wont be good doing XC and I dont care, it also hasnt impacted my other abilities as I can hop fine on it and actually manual better!

As a footnote on chainstays.

It's nice that proportional CS lengths have become a hot topic - but I find most brands who do it seem to start at "too short" and go up to "getting there" by the time they hit the XL and XXL.

Instead of 430-445mm across the range, I'd probably suggest 445-460mm.

But even better to do that and allow some adjustment.

Frames need to be shorter/longer to suit the riders height. You can't just have one length for all heights. I've noticed recently that some bikes start at a medium for 5ft 6 and above. Why no small? Or maybe its just down to stock being low.

https://enduro-mtb.com/en/enduro-race-bike-mtb-review/

This is worth a read. It is a timmed group test with team bikes that lead to some interesting observations about reach, chain stay length, the proportion of the two and also handle bar width.

"I ride bikes with 460mm and 475mm reach – and chainstays of 435mm, 445mm and 450mm."

Do you know what the chainstay lengths are at sag or how they change through the travel? Only the high pivot idler bikes get noticeably longer at sag but some bikes get a bit longer to sag whilst others get a bit shorter. And towards full travel the differences can get really big.

2019 bikes:
Orange Stage 6 = 450mm static / 453mm @ sag / 444mm @ full travel
Stumpy Evo 29 = 443mm static / 441mm @ sag / 422mm @ full travel

@mwleeds I'd forgotten about that group test. Interesting reading, especially "In size L, the COMMENCAL is the loser of this test and proof that the trend towards increasingly longer bikes has definitely reached its limit." Although it sounds like it was as much the disproportionately short chainstays that were the problem.

This is worth a read.

A "team bike" should be optimised for the team rider... who cares how fast someone else is on that bike, especially when compared to another bike optimised for another different team rider?

This combination means that you have to ride the bike very actively to generate enough grip on the front wheel when cornering.

Sounds reasonable. But perhaps some pros want to ride a bike in that way, and know how to turn it into pure speed in a way the test riders do not?

The whole test was an interesting read on the trends in setups favoured by team riders, but the timings (and labelling one bike the "loser") is all a bit silly.

Do you know what the chainstay lengths are at sag or how they change through the travel?

Good lord no.

That is interesting, but I wouldn't have the bandwidth to factor that into my bike buying along with everything else.

it sounds like it was as much the disproportionately short chainstays that were the problem.

That website has form for jumping to conclusions on the basis of partial evidence, or results which could have been influenced by a multitude of factors.

Longer and slacker certainly isn't always better, but when it is - it really is.

Was At Nant yr Arian yesterday on the Scandel. It's just under 1200 whereas my Dog is just over. TBH I couldn't tell much difference in any thing except the Scandel has a longer cocpit, even though the reach is shorter. There's no fast stuff there and the difficult definately isn't, or I wouldn't be able to do it...
The Scandel effectively has a slacker seat angle. I have the seat right forward and it's still further back than the Dogs's most rearward one. The Dog is more sit up and beg.
The seat being further back on the Scandel means it doesn't need a Dropper so much. On the Dog the seat tends to pitch you forward downhill, putting me over the front wheel which I don't like, so need the Dropper to lean back.
I scraped the 175 cranks once too so I wouldn't want a Squatch or Morph and most of my riding is cross country so I don't want a ultra steep seat angle, dropper or no.
So yes I think for many the trend is beyond optimal right now but 1200 and 65/66 doesn't seem too much for a medium. A lot of the new stuff is winch and plunge for man made trails.

I was pondering this at the weekend. My (longshot) FlareMax is great for riding down mountains on natural trails. Ideal for the sort of fairly open rocky landrover tracks that I often find myself on where it can really fly. But once I get down to the woods and the more man made trails with tight berms and various other obstacles I find it a bit of a handful with my very limited skills. Suits me as I tend to avoid anything marked as a mountain bike trail and prefer the open hilltops. But, given that most normal people prefer "proper" mountain bike trails it does surprise me a bit that bikes have become so long. Probably just a skill thing though.

More leaning of the bike required?

Yes, that and more commitment. Mincing into a "berm" and then finding you don't have enough speed to get round and it is too deep for a pedal stroke can be very embarrassing 🙂

"That website has form for jumping to conclusions on the basis of partial evidence, or results which could have been influenced by a multitude of factors."

They did a similar thing on bar width if I recall correctly. One doesn't like to stereotype the Germans too much but they do have a talent for thinking that everything can be measured - and although many things can be measured, it's not often possible to measure something in a way that can translate into journalism and be understood by laypeople. And if it's a journalist doing this so-called scientific analysis, well, it's not going to be very scientific...

Going back to chainstay length, I now swap between a 29" ebike with 455mm chainstays and a 27.5" hardtail with 420mm chainstays. Everything else about the geometry and build is similar but you'd think those four big differences (massive frame weight, bigger wheels, longer chainstays, and absence of rear suspension) would make a huge difference but I can swap between them really easily. I guess the Levo just needs earlier timing and more leverage to do anything but otherwise they behave quite alike and when I find myself dealing with anything gnarly my feet and hands are in a similar place vs the front wheel.

Watched both videos, they speak with confidence about what “suits them”, also read the link and this bit caught my attention about RAD and its founder/author:

Both riders clearly been riding a long time, grew up on BMX, spent decades riding bikes that are too small for them and have got used to riding around the inherent characteristics of smaller bikes quite clearly... If you want a Dirt Jump bike, or are only concerned with how easy a bike is to manual, then knock yourself out, go for RAD-... Doesn't work for me any more though!

Are they too long? No, I don’t think so, you can still buy small bikes if you are small, or that’s your thing, but you can also buy big bikes now if you are tall, or that’s your thing.

I know what I like & I’m probably in the realms of ‘normal’ these days.

Echos my sentiments mostly... At 5ft10 the biggest realisation I've had in the last few years is that in *most* manufacturers geometries I should be riding a Large rather than persisting with medium sized frames in general. This only tends to buy you about 20mm of reach, but generally I feel more "in" a large sized frame (sweeping generalisation I know) than perched on a medium (most notable exception being my Geometron G15 which is a Medium, I tried a friends Large and it just felt too long).

My Large XC bike has a reach of 445mm, Large eBike has a reach of 478mm, Medium Trail Bike has a reach of 490mm. Chainstay lengths are 438, 442 and 445mm respectively, and Seat angles are 74.8, 77.5 and 77 effective respectively too.

Crucially, and so much for the concept of sizing by horizontal top tube length being irrelevant these days, my saddle nose to handlebar length (so cockpit length I guess) is between 495 and 500mm on all 3 bikes...

It’s nice that proportional CS lengths have become a hot topic – but I find most brands who do it seem to start at “too short” and go up to “getting there” by the time they hit the XL and XXL.

Instead of 430-445mm across the range, I’d probably suggest 445-460mm.

I'm certainly not tall enough to decide what's long enough at the upper end, nor am I short enough to dictate what suits at the lower end... I do know that I'm happier now with a slightly longer Chainstay length than I was a few years ago. All 3 of my full sus MTBs feel very well balanced with their respective reach and chainstay lengths listed above. Previous bikes have tended to have shorter chainstays, which arguably felt snappier, but less composed in high speed corners. There's also the climbing benefits that a longer stay length brings too... To a point.

By biggest gripe is with seat angles for many/most brands... They still tend to follow the traditional roadie method of slackening the seat angle slightly as frames get larger (though head angles thankfully don't tend to get steeper still, that stopped a long while ago on MTBs). This is totally counterintuitive, and is a pure old school roadie hangup for trying to minimise the wheelbase growth of a road bike as the sizes get larger. There's VERY few companies that have bucked this trend... Geometron being an obvious one, Vitus have started steepening their seat angles as the size gets larger too, I am sure there are a few others but they are the exception not the norm still.

The focus still is in many cases, and always was, on keeping the wheelbase down to a practical minimum, where actually the wheelbase length should just purely be a byproduct of putting all of the contact points in the correct place, combined with desired angles etc... Anyway...

It's becoming increasingly clear for the more educated of customers that "balance" is key... My XC bike has a wheelbase of approximately 120mm shorter than that of either my eBike or my trail bike, but it feels superbly balanced still, and I'm fast on it even where you wouldn't necessarily expect an XC bike to be quick as a result. I've seen many modern Enduro bike reviews where the testers have commented about the bike having a much longer reach than previous iterations, but no extra length in the rear end and as a result, feeling less balanced and therefore being slower against the clock despite increased reach figures. Clearly MTBing isn't the "point and squirt" sport that some of the manufacturers would have us believe with their geometry and marketing!

The fastest bike I've owned was a Trek Session 88. I think it was a 2010. It was a medium and had a reach of 390mm I think. It's a long time ago now but it felt perfect and was very fast, fun and confidence inspiring for me when riding down hill tracks in the Alps, Spain and in the UK. I've just checked and the current session has a reach that is 18mm longer. I've no idea if Trek are an anomaly here and if most downhill bikes have grown in length with trail and enduro bikes, or if downhill bike geometry hasn't really changed generally in the last 10 years. Possibly a bit of both as I think Trek do stick to the conservative side of geometry changes/trends.

I also owned a Strange Alpine five. I can't remember the geometry numbers but it was a prototype orange frame that singletrack once reviewed. It was probably built around 2008. It also had a reach of 390mm but was also very slack with a longer wheel base than some of my mates DH bikes at the time. It was also an amazing bike to ride in the alps down very steep, very rough trails. Both bikes were very capable descenders that I struggle to imagine would be quicker or 'better' bikes with longer reach. It's tempting to say that they were amazing because they both had slack head angles but that's probably not true - it was probably also that everything else was just right (for a very specific use!) eg. CS length, BB height etc.

I'm not sure what my point is. Probably that slack and short (by modern standards) bikes were and are still very quick and that (some) downhill bikes don't appear to have been effected by the slacker and longer trend.

But perhaps modern slack AND long bikes take what was great about my previous bikes and makes them better everywhere else...I've no idea as I've yet to ride one 🙂 It's good to keep a open mind though and it's interesting to read about RAD as an alternative to the longer and slacker trend. In the past I've very rarely test ridden bikes but I think that now with the rapid changes in geometry it's getting a bit riskier to buy new without a proper test ride - not helped of course by the fact that bikes are more expensive than they used to be.