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Modern geometry/old fashioned geometry
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ioloFree Member
Could someone please explain to me why modern geometry is “better ” than old geometry?
I’ve been riding for over 25 years (mostly in Coed y Brenin ) and enjoyed most of the bikes I’ve had.
Why is modern geometry so amazing? Emperors new clothes?BreganteFull MemberIt isn’t necessarily.
It’s all marketing. People want the latest shiny.
brantFree MemberAs people started riding clunker bikes uphill rather than just downhill, seat angles steepened to get riders in a better power position. For fast handling on smooth race circuits, angles steepened. Suspension forks came along as frames we modified to give the same handling as those rigid bikes but with springs at the front.
As forks got longer (Judy DH forks used to be just over 70mm travel remember), geometry had to adopt the the greater range of movement throughout the stroke.
Rear suspension caused some seat angles to steepen so the rear wheel wouldn’t bang into the seatpost.
Head angles slackened as forks became longer and speeds became faster.
Wheelbases lengthened as top tubes/reach extended to allow faster (yet slower) steering with shorter stems.
BB’s dropped as people realised it didn’t matter how high you made them, you’d always bump them on something, and lower bikes were easier to get on and off.
And lo, the trails became more alive.
deanfbmFree MemberThe main one would be old geometry relies on a long stem in order for the bike to “fit”, this is a hangover from road bikes, MTBs aren’t road bikes, they shouldn’t be treated as such.
MTBs have to deal with rough ground, turns, obstacles, jumps, a combination of all just mentioned, road bikes don’t. In order to deal with this, your weight should ideally be central in the bike and you want to build in stability so the rider doesn’t just get instantly ejected.
On MTBs too, you should really be standing when ever you’re on anything other than smoother trails, telling the bike to do things properly or jumping, so a MTB also has to fit whilst standing, not just seated.
I could just waffle on some more, but going to cut the story short and go straight to the summary –
– “Old” geometry is based on road bikes
– Old geometry is based on fitting seated, with a long stem
– Road bikes and MTBs should not be treated the same, totally different applications
– New geo puts more emphasis on handling and fit standing, more stability built in and more central weight distribution so the rider is in a better place to tell the bike what to do as well as the bike being less sensitive to the inputs from the terrain.Basically, old geometry is just WRONG, that’s the gist of it.
ioloFree MemberOk. So how have geometry changed in say the last 10 years or so?
I have an SWorks Endoro 2006. Fox 36rc2 coil, Dhx air (not the best as it blows through travel) with 150mm front and back, 30 mm stem. The bike fits me perfectly.
Does a new 2016 bike ride better? I don’t care about wheel size, I’m talking about geometry.horaFree MemberIts a progression and gradual improvements over time. Things improve because more people ride off road. In the beginning there were the clunkers ridden fast down fire roads. More people I.e more customers means more money more development.
Some are classics though- Blur4X with its steepish head angle. Then there’s the updated classics; Blur, Heckler etc.
kudos100Free Memberimprovements in geometry along with disc brakes, dropper posts and decent suspension are some of the things that have actually made a difference to how people ride/can ride mountain bikes.
of course you can ride a bike with a head angle and stem similar to a road bike, but it’s a much better with a shorter stem and slacker head angle.
deanfbmFree MemberGotta look at the whole package, wheel size, suspension.
Just demo a brand new bike, i guarantee it will be a night and day, OMG, “why didn’t is do this sooner” moment.
Words on a screen isn’t going to explain it.
rentonFree MemberSo hora let me get this straight. You like the steepish head angle on the blur 4x but said the Turner I have was shit because of the steep head angle ??
ioloFree MemberYou say night and day. In which way?
Better climbing, descending, cornering?
My bike is slack, low bottom bracket, short stem, wide bars and goes like a rocket (when I’m fit).
I am just looking at whether or not I should upgrade but if there’s not much difference, what’s the point?TooTallFree MemberSo hora let me get this straight.
Dumbass. Taking notice of what hora said about a bike was a schoolboy error.
kudos100Free Memberin the last ten years, less so. over 25 years, quite considerably.
RorschachFree MemberI had a 65 degree HA,sub 13″ BB,steep SA (seatpost flipped forward),160mm(ish),50mm stemmed bike in 2008 (patriot66 one size too big and with a shorter shock).Fitted with 750mm wide renthal speedway bars.
Modern my arse.horaFree MemberWhoa Santa Cruz got a mix/collection of TT/ST etc measurements and angles RIGHT. Hence why its still great to ride in pretty much most situations. Don’t cut corners and misrepresent what I said. Renton your selling the bloody 5spot thing for a reason. Tootall back under your bridge. Or open your mouth and positively contribute for once?
A bike isn’t all about one angle. Otherwise every bike would ride the same.
kayla1Free MemberMy bf had a 2009 Carrera something-or-other and when I took it out a few months ago it felt really odd (old?) compared to my (then) 2013 Sunn Tzar. My 2008 DMR Exalt feels different again, going from the Sunn to the DMR it felt like the BB was under the head tube just because the DMR seat tube angle is a couple of degrees slacker. They have the same, or thereabouts, head angle and take similar length forks.
Horses for courses I suppose. I prefer slacker angles and stuff because they tend to be more comfy and I’m old and not racing XC. I love my Sunn but the DMR gets dragged out if I just want to play out on a daft short bike.
To conclude, the bike industry moves its goalposts in order to get you to buy more stuff. I think, possibly, they’d struck gold with the ‘new’ slack hardtail trail geometry with 26″ wheels and had nowhere else to go but 650B.
ioloFree MemberTrue, I loved my 456. The only reason I got rid of it was due to my knackered back.
chiefgrooveguruFull MemberYour Enduro was pretty far ahead of its time – the “Emperor’s new clothes” is a continuation of that progression.
The truly wrong geometry era was the early-mid ’90s where MTBs became too much like road bikes, massively compromised downhill and at speed in exchange for better climbing and low speed control. The original klunkers were relatively slack, low bottom bracket and long wheelbase, hence good at descending – current geometries are surprisingly close to that.
juliansFree MemberIolo – I have an enduro of the same vintage as yours, as well as a bang on trend nu skool geometry 2015 Orbea Rallon. The enduro is my spare bike for when the rallon is broken.
Your enduro was one of the first bikes to start to head in the direction of what is now the new geometry.
If you like the enduro , you’ll like the newer stuff even more, its like the enduro ,but better, better climbing, better descending, better at just going along, not to mention the advances in making stuff lighter and stronger.
Your enduro still rides well, I know because I have one almost identical in spec to yours, but the new stuff rides better. Less of a difference than you might feel if you had a different bike though because that era (2005 & 2006) of enduro was way ahead of its time.
deviantFree Memberiolo and Rorschach, both your bikes were ahead of their time….all that has changed is that 5-10 years ago people wouldn’t have dreamt of taking a Spesh Enduro or Orange Patriot for an all day ride, they were seen as Alps bikes, very much niche….the wider public were buying 100mm XC bikes and wondering why truly challenging terrain was a pain in the arse.
People want to ride tech stuff on a daily basis now so the typical FS these days is designed to allow this, the Patriot effectively became the Alpine-160 and the Enduro’s geometry that was ahead of the curve in 2008 is now the norm.
I rode the same trails in the 90s I do now, only then I rode a rigid GT Avalanche, modern angles haven’t changed what I ride they’ve just made it a whole lot easier.
rentonFree MemberInterested in this too as in my other thread people are saying my 5 spot geometry is crap yet it’s only a degree off the enduro in the slack setting but the sAme in the high setting.
rentonFree MemberOh and hora. My five spot has a half degree difference in head angle and half inch in top tube length compared to an 09 blur 4x.
Go figure
ioloFree MemberDeviant, my Enduro has done all day rides since I got it. It’s actually perfect for that.
jam-boFull Memberall that has changed is that 5-10 years ago people wouldn’t have dreamt of taking a Spesh Enduro or Orange Patriot for an all day ride
oh we did….
deviantFree MemberIf it’s that good keep it then Renton!….it’s not just the geometry Renton, the headtube makes tapered steerers an impossibility and tapered steerers tend to be the norm these days….if you drop the price someone will take a punt on it but for 1k I’d want at least a 44mm or tapered headtube and for long travel full-sus I’d want a head angle of 65-67 degrees and the ability to take a 160mm fork….there are bikes out there with new standards, nu-skool geometry etc for a lot less than 1k second hand and only £1500 brand new!
For the pedants above saying they rode their long, slack and low Enduros and Patriots on all day rides, well done you….take a look at most MTB mags from 10 years ago and look what was being reviewed as a typical trail bike, it wasn’t stuff like the Patriot!
Bully for you for being ahead of the curve, when I bought a Trek 4500 in 2008 the showroom was full of similar bikes, a 120mm full-susser was an unattainable object of desire and stood proud among the masses of short travel hardtails…the same shop now has rows of slack angled long travel Nukeproofs, Kona Processes and Lapierres…but you’re probably right, things haven’t changed at all.SaccadesFree MemberMate has an ancient rockhopper – with some almost correct vintage biscuit tyres.
I had a go and on tarmac it was grand, on grass/mud it felt like it was going to slip at any point, it just squirmed constantly. He’s a better and fitter cyclist than I am, but on a lap of bonty I kept up with him and you could see him struggling on the downs.
Tyres and geometry certainly increased my confidence in my more modern bike (456) and I wasn’t having to make loads of corrections to keep on course (most probably tyres, but when it got steep he was struggling to get his weight back he was so arse in the air).
I do think that now so long as you pick the geometry for the application you’ll be grand. I have a short travel race (ish, I’m a hefty fella) XC bike for summer epics and a 456 for general blatting about.
singlespeedstuFull Member**** me. Hora posting on a thread about bike geometry.
That is funny.chestrockwellFull MemberI love it when the STW brains trust jump on threads like this. 😆
Modern geometry is not necessarily better, it just suits the time and current riding trends. Are XC race bikes slack with 0mm stems?
I’d listen to Brant as he’s been in the thick of it from close to the start.
chickenmanFull MemberI think Iolo answered his own post when he said he mainly rides at trail centres. Trail centres are built not to be steep, not to be narrow, not to have tight bends; basically not to have any nasty surprises. Someone like myself who rides far too slowly down steep natural stuff was always likely to catch (on a steep angled bike) the front wheel against obstacles resulting in an OTB. Modern long + slack gives you much more fore + aft stability at the expense of being less stable side-to-side at slow speeds.
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