Door to trail riders - tell me how you've accommodated these crazy steep seat angles please

Posted by: kcy4130

Posted by: geraldooka

Ha I like the painful seat idea ;-) I have pretty cushy grips with the ESI's I may try a more backswept bar that may work, although I am already using the 30x 12deg which has a decent back-sweep that eats up about 45mm of cockpit length.

Did the 12deg bars help? I'm curious if they'd help me. I hesitate to spend much just to try them tho. As an experiment you could try over pressuring your fork so you have barely any sag for the road portion of a ride, hence slackening sta. If you like it, it'd at least give you a data point on what to aim for in future.

Yes I have a hard time going back to bars with less sweep now at least at the width I run my mtb bars which is 760-780. The issue with the 30x is that measure rise different form literally everyone other manufacturer so their 45mm "high-rise" is really more like a 30 (if that). I have found another manufacture called Ergotec that makes higher rise bars that are also really comfy at 12deg backsweep. I have a 50 and 75mm rise (they are actually 50 and 75mm high). I like you're idea re fork pressure I have used that technique to figure out where I may be happy.

Re bar height here's the issue with raising the front end too high for me: So with longer reach and steeper seat angles I have to raise the front end to ride anything other than up and down to achieve some level of comfort. On trail I suffer the consequences of this now high front end which for me manifest in a harder time getting up and over things particularly when climbing tight switch backs and suddenly "ooof" I gotta hump the front up a ledge with the reduced leverage because my arms are way up already and then get over this high front end so that my rear wheel can get over the ledge...

I'm starting to think I am riding bikes that are too long for me... At 5'8" I've generally gone Medium but nowadays todays Medium is yesterdays large...

I may also have longer than average femur length but I have been told its not that unusual. Sitting on a chair and bringing my chest to my thighs my shoulder sits about 90mm behind my knee. For comparison my wife's (5’5”) shoulder is past her knee by about 15mm so clearly I have a shorter torso to femur length relative to her but I don't know if its that unusual... This could explain my issue with steep seat angles. 

I did just complete a bike fit but I'm not sure how helpful it was, they basically just confirmed where I was already happy at, which is the nose of the WTB pure between 40-50mm behind the BB (with 165mm cranks) and they have zero MTB experience so... That happy setback is not possible to achieve even with a 25mm setback post on most bikes with => 75deg seat angles at my pedalling height...

Compare yourself to a similar height man, women are built differently in terms of body proportions among other things

Also, measuring torso length based on folding at the waist is not really hownits done. How far your shoulders go over your knees is probably more a feature of hip/spine flexibility (as well as beer gut size) than it is torso length. Your wife may have a longer torso but she also may just be more flexible. I think height to inseam ratio would be a better metric for torso length.

Posted by: RAHrider

Also, measuring torso length based on folding at the waist is not really hownits done. How far your shoulders go over your knees is probably more a feature of hip/spine flexibility (as well as beer gut size) than it is torso length. Your wife may have a longer torso but she also may just be more flexible. I think height to inseam ratio would be a better metric for torso length.

Torso length the vertical distance from the top of your hip bones to C7 (bony bump on the back of your neck).

I'm 5'11" with a 22" torso, which is considered very long for my height. 

This makes the problem discussed in this thread even worse because with a long torso the bars feel lower (I feel like I almost can't get a high enough stack to really make any bike feel totally neutral - hands always feel heavy). 

Trouble is when standing up I'm still only 5'11" so I can tend to add too much stack in the name of comfort and then be prone to front wheel washout.

I suspect your both right. It was not intended to be scientific but a quick seat of the pants observation. :)

A rare photo of Geraldooka in the wild. You can see why our nickname for him was The Femur! ;-)

That’s the gnarliest terrain photo you could find of me!? Well at least I’m in plaid. 🤷‍♂️

Posted by: geraldooka

That’s the gnarliest terrain photos you could find of me!? Well at least I’m in plaid. 🤷‍♂️

When you are in full send mode it's unlikely I could get a reasonably clear profile shot given my meager photo gear. At least you are riding a sweet bike. 👌

Have you got other bikes in the fleet? An old bike that's more comfortable on flat ground? A good reality check is to simply measure seat to grips. Center to center and compare. Looking at effective tt length is not exactly the same as stem, seat rail position backsweep, stack etc affect it.

It might be that you'd benefit from sliding the seat all the way forward on the rails. Let me explain, if we ignore sta and ones legs and only look at the upper body, then a shorter distance from seat to bars will allow you to sit more upright, i.e. spine closer to vertical and less sloped forward. This means the cg of your torso moves back slightly, hence more weight on seat, less on hands. Now, if we put legs and sta back in then a steeper sta will reduce a riders ability to hold up the torso with back/butt muscles with the feet as fulcrum, hence less weight on hands. Which of these conflicting things will be the dominant factor depends on specifics. If you are indeed on too long of a bike then sliding forward could help. Or I could be completely wrong, but hey, it's free and easy to try.

Edit: This means the cg of your torso moves back slightly, hence more weight on seat, less on hands. Now, if we put legs and sta back in then a steeper sta will reduce a riders ability to hold up the torso with back/butt muscles with the feet as fulcrum, hence more weight on hands.

Posted by: kcy4130

It might be that you'd benefit from sliding the seat all the way forward on the rails. Let me explain, if we ignore sta and ones legs and only look at the upper body, then a shorter distance from seat to bars will allow you to sit more upright, i.e. spine closer to vertical and less sloped forward.

On the surface this seems right but I've not found this helps as much as I'd have hoped.

The reason is that your legs play a role in keeping you upright. Imagine a recumbent bike where your pedals/bottom bracket are way out in front of you. This is like an extreme version of a slack seat tube angle. Because you're basically laying back you aren't going to have any weight on your hands regardless of there the bars are, because your legs are in front of you, you're inherently leaned back. 

Now incrementally imagine the recumbent bike morphing with the bottom bracket travelling rearwards towards you. It will progressively tip you forward and your legs are less and less able to actually support your torso.

Imagine you get to the other extreme where the bottom bracket is behind you (seat tube angle greater than 90 degrees). At that point the opposite of the recumbent is true, no matter your bar positioning, your weight will be on your hands.

The steeper seat tubes get the closer bikes get to this latter scenario. Putting your feet further "behind" you increases pressure in most cases even if it shortens the cockpit.

Shortest stem and tallest stack you can handle help but again might compromise other riding.

This is why personally I just don't like steep seat tube angles for *trail* bikes that see a variety of terrain. Give me a seat like a Koda with a comfortable climbing nose to I can scooch forward if I need to and effectively steepen things a couple degrees in the rare case I truly need it, and a 74-75 degree STA. For Enduro bikes where the priority is steep up steep down, and sit and spin climbing, and more travel and therefore more rear suspension sag when climbing, bring on the steep seat tube angles.

My opinion is the bike industry sometimes latches on to something "cool" and just carpet bombs their entire product range with the feature, regardless of if it's actually appropriate for the different use cases.

Posted by: geraldooka

I'm starting to think I am riding bikes that are too long for me... At 5'8" I've generally gone Medium but nowadays todays Medium is yesterdays large...

I'm 5'11" with a 33" pants inseam and my go to frame size in the "modern" era is a Medium. I can make a M/L or L work, but there is always some compromise. I wouldn't hesitate to downsize your frame if you think that's the right move. Let's be honest if you are riding a stubby 30/35mm stem now you can go up to a 50mm stem on a smaller frame and get nearly a whole frame size in adjustment room without feeling like you are riding some 90's NORBA XC beast with a 120mm stem. Going the other way if you are already at a 30/35mm stem there isn't much room to adjust things in the smaller direction. You are left with bar sweep/roll.

In terms of fit I think the smart move is to:

1. Get your saddle/BB relationship optimized
2. Adjust the distance to the bars for comfort

If you are riding too big a frame you can't do that ^^^. You end up forced to use the shortest stem you can and then adjust the saddle/BB to make things fit. The result is less than ideal.

I've been there and done that. Going forward I'll err on the side of the smaller frame. Keeping in mind today's "smaller" frames still have some pretty epic wheelbase numbers compared to what we were riding 10 years ago.

I agree with Vik. I'm in between L and XL most of the time and with most bikes I've ridden in recent years I've gone with the L and it has worked pretty well for me.

Having said that, for an upcoming test bike the L looked a bit shorter than what I'm used to so I've requested an XL which is longer than anything I've ridden. It will be interesting to see if I'll experience any of the issues mentioned in this thread.

Posted by: Kenny

Posted by: kcy4130

It might be that you'd benefit from sliding the seat all the way forward on the rails. Let me explain, if we ignore sta and ones legs and only look at the upper body, then a shorter distance from seat to bars will allow you to sit more upright, i.e. spine closer to vertical and less sloped forward.

On the surface this seems right but I've not found this helps as much as I'd have hoped.

The reason is that your legs play a role in keeping you upright. Imagine a recumbent bike where your pedals/bottom bracket are way out in front of you. This is like an extreme version of a slack seat tube angle. Because you're basically laying back you aren't going to have any weight on your hands regardless of there the bars are, because your legs are in front of you, you're inherently leaned back. 

Now incrementally imagine the recumbent bike morphing with the bottom bracket travelling rearwards towards you. It will progressively tip you forward and your legs are less and less able to actually support your torso.

Imagine you get to the other extreme where the bottom bracket is behind you (seat tube angle greater than 90 degrees). At that point the opposite of the recumbent is true, no matter your bar positioning, your weight will be on your hands.

The steeper seat tubes get the closer bikes get to this latter scenario. Putting your feet further "behind" you increases pressure in most cases even if it shortens the cockpit.

Shortest stem and tallest stack you can handle help but again might compromise other riding.

This is why personally I just don't like steep seat tube angles for *trail* bikes that see a variety of terrain. Give me a seat like a Koda with a comfortable climbing nose to I can scooch forward if I need to and effectively steepen things a couple degrees in the rare case I truly need it, and a 74-75 degree STA. For Enduro bikes where the priority is steep up steep down, and sit and spin climbing, and more travel and therefore more rear suspension sag when climbing, bring on the steep seat tube angles.

My opinion is the bike industry sometimes latches on to something "cool" and just carpet bombs their entire product range with the feature, regardless of if it's actually appropriate for the different use cases.

Crap, I wrote less instead of more. edited now. Yeah, I was trying to explain that side of it too. Which effect will be have a larger impact on hand weight totally depends on the individual and specific bike/body geo. But a quick experiment is the easiest way to find out. 

And I agree about carpet bombing (great phrasing btw) trends. When it comes to bikes (and lots of other stuff where marketing is involved) there's a lot of the fallacy of "if some is good, then more is better" going around.