[Kiwintas]

Exactly. That’s my beef, how much harder it is for me to wheelie drop with the long bikes.
And yes, that is proof that I kinda suck.

Oddly, out of the bikes I own the easier one to get the front wheel in air with is the one with the longer reach as it also has the shorter chain stays.

Probably need to bring ETT length back into your comparisons, rather than just reach.

that's what I have started to pay attention to when looking at bike sizes. Reach numbers by themselves get a bit funny with steep seat tube angles

A steeper seat angle does not change how the bike fits and rides when you are standing up (aka descending). Unless you want to quibble about steering with your knee on the side of the saddle.

Feeling comfortable or cramped during seated climbing and feeling comfortable or cramped on a descent are different things.

Sorry for being Captain Obvious.

On a trail bike I would guess that you spend more time seated than standing, so would not the fit on the climbs be important to? I also find the new school longer reach/ETT gives you a larger sweet spot to centre you weight in front of the BB when descending vs the old school shorter reach/ETT which meant that most of the time you have to be directly over or behind the BB which made it more challenging to change directions in a hurry.

 

[Bike078]

About 5'7", longish arms. Bike is a medium dartmoor hornet. 430 mm reach, 620 mm stack, 425 mm CS, 1,176 WB. 40 mm stem and 740 mm handlebars. Tried 760 mm bars but it felt a bit wide when on the flats and climbing.

 

[HardtailHack]

6ft tall, ride a hardtail, poorly.

Went from 417mm reach with a 50mm stem and a 5deg back bar to 468mm reach and thought I was going to take a bit to adjust but with a 35mm stem and a 9deg back bar it still felt too short.
Swapped back to a 50mm stem and a 5deg backsweep bar(770mm), it's a bit better but I would rather be on a 500mm reach frame with a 35mm stem, next time.

 

[ChrisRobin]

that's what I have started to pay attention to when looking at bike sizes. Reach numbers by themselves get a bit funny with steep seat tube angles

Yeah I think ETT will be making a bit of a comeback...or at least for me, that's one of the numbers I'm watching since I'm looking for a new AM/Enduro frame.

 

[Katz]

...On a trail bike I would guess that you spend more time seated than standing, so would not the fit on the climbs be important to? I also find the new school longer reach/ETT gives you a larger sweet spot to centre you weight in front of the BB when descending vs the old school shorter reach/ETT which meant that most of the time you have to be directly over or behind the BB which made it more challenging to change directions in a hurry.

I think that depends on what your priorities are. Indeed, I climb more than descend while riding my local trails and I do enjoy clearing some techy stuff going uphill, but ascending is still just means to an end for me.

So the way I choose my next bike would be....
- steep seat tube angle for less fatigue on legs pedaling (also gets the saddle out of the way better)
- then pick reach and stack that place my neutral body position for balanced feel while jumping and cornering, taking other factors in consideration (chainstay, stem length, fork offset, etc)

I can live with whatever ETT I end up with, honestly shorter the better for me as I have one bulging disc in my back. My back hurts less with more upright position. Also I can adjust this to an extent by sliding the saddle fore/aft.

IMO, you should define what is the right approach for YOU before you look at the geometry chart.

Agreed on a larger sweetspot on a longer bike.

 

[Sandwich]

with all the steep seat angles these days, has anybody considered biodynamics and knee position? I certainly like a pretty over the nose saddle position, even my road bike is slammed pretty far forward, but some of these seat tubes are getting intense. Paired with a longer front end, you're going to be way over the nose of the saddle, which might kill efficiency. Not that mountain bikers give a fuck about that because spirit of enduro and shit, but I wonder if people with sensitive knees will hate it.

 

[Bikael Molton]

Yes, but at what climb grade do you determine over the nose? Do you look at KOPS with the bike at an 8° angle? I don’t pedal my mountain bike on flat ground very much.

I think there’s the rub with mountain bike fit for seated pedaling, and why there won’t ever be an optimum that works for all riders.

I’d like a steeper STA on my next bike, but I also want a <63 HA and I don’t need to add more WB.

Damn, I apologize for talking about climbing on here, guys.

with all the steep seat angles these days, has anybody considered biodynamics and knee position? I certainly like a pretty over the nose saddle position, even my road bike is slammed pretty far forward, but some of these seat tubes are getting intense. Paired with a longer front end, you're going to be way over the nose of the saddle, which might kill efficiency. Not that mountain bikers give a fuck about that because spirit of enduro and shit, but I wonder if people with sensitive knees will hate it.

 

[marshalolson]

with all the steep seat angles these days, has anybody considered biodynamics and knee position? I certainly like a pretty over the nose saddle position, even my road bike is slammed pretty far forward, but some of these seat tubes are getting intense. Paired with a longer front end, you're going to be way over the nose of the saddle, which might kill efficiency. Not that mountain bikers give a fuck about that because spirit of enduro and shit, but I wonder if people with sensitive knees will hate it.

Not for efficiency per-se but for comfort, I went from always using straight post w/ saddle slid a bit forward on “slack” 72deg seat tube bikes to having to use setback dropper post and the saddle slid a bit back on “steep” 76deg seat tube bikes...

 

[toodles]

with all the steep seat angles these days, has anybody considered biodynamics and knee position? I certainly like a pretty over the nose saddle position, even my road bike is slammed pretty far forward, but some of these seat tubes are getting intense. Paired with a longer front end, you're going to be way over the nose of the saddle, which might kill efficiency. Not that mountain bikers give a fuck about that because spirit of enduro and shit, but I wonder if people with sensitive knees will hate it.

FWIW, other forums have debated this a bit. Personally I think its no biggie unless you're riding a flat traverse for a very long time. Mostly people just ride uphill, then descend on the enduro rigs.

Also even a 77-78º SA isn't that ridiculous when you take sag into account on a >150mm bike.

 

[Udi]

with all the steep seat angles these days, has anybody considered biodynamics and knee position? I certainly like a pretty over the nose saddle position, even my road bike is slammed pretty far forward

Excessively off-topic discussion in DH forum, reported.

 

[Sandwich]

sorry, disregard, go back to measuring your wheelbases in quarter miles, my bad

 

[6thElement]

sorry, disregard, go back to measuring your wheelbases in quarter miles, my bad

I measure mine in beard seconds.

 

[englertracing]

with all the steep seat angles these days, has anybody considered biodynamics and knee position? I certainly like a pretty over the nose saddle position, even my road bike is slammed pretty far forward, but some of these seat tubes are getting intense. Paired with a longer front end, you're going to be way over the nose of the saddle, which might kill efficiency. Not that mountain bikers give a fuck about that because spirit of enduro and shit, but I wonder if people with sensitive knees will hate it.

Personally I like to be up over the front while seated, a Lil weight up front for da turnz.
I also run my seat high af at full extension. Probably 1/4"+ or so higher than a bike fit would give
I think there is a correlation between high af and forward, vs rear af and not so high.
I mean aside from/in addition to the direct correlation of the post moving the seat back as its elevated.
But slack seat tubes and set back posts are gross as Fuck to me, they are for the days before you could drop me and get them out the way. Also kops is probably bull shit.
Also I tore my acl never had it repaired I'm a bad knee guy. Well not really doesn't bother me much anymore.

Not for efficiency per-se but for comfort, I went from always using straight post w/ saddle slid a bit forward on “slack” 72deg seat tube bikes to having to use setback dropper post and the saddle slid a bit back on “steep” 76deg seat tube bikes...

Why
Are you by chance really short?

 

[marshalolson]

Why
Are you by chance really short?

6’2’’
Seat high
Formally trained bike fitter

Saddle position is in many ways about where you knee is in relation to your pedals... and as such, how long your femur is in relation to your inseam.

 

[kidwoo]

Formally trained bike fitter

Saddle position is in many ways about where you knee is in relation to your pedals... and as such, how long your femur is in relation to your inseam.

I just ate shit riding after work and my saddle slammed into my pee pee (true story). How do I keep that from happening in the future?

Let me know if pics would help.

 

[djjohnr]

I just ate shit riding after work and my saddle slammed into my pee pee (true story). How do I keep that from happening in the future?

Let me know if pics would help.

Gender re-assignment. Clearly.

 

[jstuhlman]

I just ate shit riding after work and my saddle slammed into my pee pee (true story). How do I keep that from happening in the future?

Let me know if pics would help.

you have a distinct lack of carbon bars, obviously

 

[kidwoo]

you have a distinct lack of carbon bars, obviously

You can tell because I wasn't waving half a bar in the air when I stood up

 

[slimshady]

you have a distinct lack of carbon bars, obviously

You have a distinct lack of daylight riding, obviously.

 

[englertracing]

6’2’’
Seat high
Formally trained bike fitter

Saddle position is in many ways about where you knee is in relation to your pedals... and as such, how long your femur is in relation to your inseam.

Why does getting the knee over the pedals matter?
wasn't KOPS discredited?
weather your laying down on a recumbent, or standing up sprinting, there will always be an imaginary line from pedal center line to your knee that will pass through your knee at some point in the cranks rotation. You know when you stand your WELL forward of the "bike fit seated position" .What is wrong with moving your seat closer to your standing position. You know higher and forwards?
are you sure you actually like riding back there and your just not used to it, and "SURE" that its better for pedaling performance.

I ride a lot of shit MX, Hard Enduro, Supermoto, DH, Trail.
note the distinct absence of road bicycles
To me being back on a bike is NOT how you exercise maximum control, I also think its a carry over from when seats were high and droppers didn't exist, it was sort of a compromise so you could ride more stuff with your seat up high.
on flat sections or gentle climbs I get going pretty fast, and I personally like to have enough weight on the front to turn the bike. on steep climbs slack sta and setbacks are just horrendous

but to each his own i guess.

 

[Sandwich]

I'm not arguing in favor of being way over the back of the bike with a slack seat angle. That doesn't work (I'm looking at you, Evil Bikes). I'm arguing against being way over the front of the pedals, or rather I'm arguing in favor of being centered in a position that allows good climbing and some descending all while seated. I do not know how the 40 smoot long reaches and 90* seat angles ride, but I'm wondering if that's giving up some long-ride efficiency in favor of a great body position while standing and a barely acceptable seated climbing position. I don't know- that's why I'm asking.

My evil was way over the back, and it was terrible. My BMC is very centered and it rides great on new england trails that go up and down- I stay seated as the trail undulates...but I have wondered if I'm missing out on something with 30mm extra reach, so that's why I started the thread.

 

[englertracing]

With 30mm extra reach wouldn't you wanna sit 15mm further forward to balance the bike?

Otherwise it's gonna push......

 

[HAB]

I'm not arguing in favor of being way over the back of the bike with a slack seat angle. That doesn't work (I'm looking at you, Evil Bikes). I'm arguing against being way over the front of the pedals, or rather I'm arguing in favor of being centered in a position that allows good climbing and some descending all while seated. I do not know how the 40 smoot long reaches and 90* seat angles ride, but I'm wondering if that's giving up some long-ride efficiency in favor of a great body position while standing and a barely acceptable seated climbing position. I don't know- that's why I'm asking.

My evil was way over the back, and it was terrible. My BMC is very centered and it rides great on new england trails that go up and down- I stay seated as the trail undulates...but I have wondered if I'm missing out on something with 30mm extra reach, so that's why I started the thread.

My $0.02, as a long term owner of a Geometron: It works great if you live somewhere (as I do) where a normal ride is however many laps of climbing 1-4k feet at at a time, and then descending right back down that. The more rolling and less steep the terrain gets, I think more middle of the road geometry starts making more sense.

 

[Sandwich]

My $0.02, as a long term owner of a Geometron: It works great if you live somewhere (as I do) where a normal ride is however many laps of climbing 1-4k feet at at a time, and then descending right back down that. The more rolling and less steep the terrain gets, I think more middle of the road geometry starts making more sense.

how long is your geom?

this is the exact opposite of my terrain. I have 40ft up or down followed by 40ft in the opposite direction. Longest climbs are like 400ft followed by somehow flat terrain....which is why I like being centered.

 

[HAB]

how long is your geom?

this is the exact opposite of my terrain. I have 40ft up or down followed by 40ft in the opposite direction. Longest climbs are like 400ft followed by somehow flat terrain....which is why I like being centered.

500mm reach, 1310mm WB. I'm 6' tall.

 

[marshalolson]

M

Why does getting the knee over the pedals matter?
wasn't KOPS discredited?

but to each his own i guess.

Haha, all good man.
I am not dropping a plumb bob.

KOPS/fit kit is an approximation & easy to find starting point in a bike fit, not the final word.

Just saying what is comfortable for me to highlight not everyone is the same.

That means knee over pedal (roughly), and Fine tune from there for control of the bike while technical climbing.






.

 

[Cerberus75]

I'm not arguing in favor of being way over the back of the bike with a slack seat angle. That doesn't work (I'm looking at you, Evil Bikes). I'm arguing against being way over the front of the pedals, or rather I'm arguing in favor of being centered in a position that allows good climbing and some descending all while seated. I do not know how the 40 smoot long reaches and 90* seat angles ride, but I'm wondering if that's giving up some long-ride efficiency in favor of a great body position while standing and a barely acceptable seated climbing position. I don't know- that's why I'm asking.

My evil was way over the back, and it was terrible. My BMC is very centered and it rides great on new england trails that go up and down- I stay seated as the trail undulates...but I have wondered if I'm missing out on something with 30mm extra reach, so that's why I started the thread.

I'm in Western MD chunky but more rolling. My Riot has a 77° STA and it's a bit much. And find I have too much weight on my hands if I ride a long time at 77°. I have a 9 point 8 post so changing offset is easy. With the offset I'm at about 75.5°.I travel to Pisgah twice a year and love the steeper angle there.