SADDLE HEIGHT..please try the "bump test"

[531colin]

This is the time of year when the winter bike has come out, and I haven't ridden it for months, so it all feels "wrong". Added to that, I'm trying to get my saddle set on various bikes so I can instantly change it depending whether I'm wearing shoes or boots.... makes less than 5mm difference, but it still makes a difference.
You need "a bit" of bend in your knee when the pedal is furthest away from you and your foot is level....but how much is "a bit"....?



In the photo above, my knee is flexed and my foot is level.....if I straighten the knee, the heel goes down. At a "low" saddle height, if I repeatedly straighten then flex my knee, I can feel a "bump" as my knee locks out. (A bit like when a Q/R "goes over") Seems to work better if I'm freewheeling than propped against the wall.
My pet theory at the moment is that when I get a "bump" (knee locking out) the saddle is a few millimetres too low, so I raise it until the "bump" goes, and that's my saddle height. (In fact, I raise the saddle until the "bump" has gone in one leg, and is still there in the other leg, but that's a different matter..... )

So it would be really useful if some experienced cyclists would try this for me, and see if their "favourite" saddle position is "just above the knee lockout"....if this works in a decent proportion of cases, it could be really useful for "new cyclists".
You don't need to lose your saddle height adjustment, just put a bit of tape on the seatpost 10mm above the top of the seat tube, and you can always get back to where you are now.

[Mick F]

The "bump" as you call it is when the knee "locks out".
This is the standard way you stand still and upright, rather than using leg muscles to hold your weight.

For more years than I care to remember, I've been unable to lock out my left leg without pain. These days, my right leg is starting to go the same way. Although I can see what you're asking, I don't think I can do your experiment - as much as I'd dearly want to. My leg muscles are very well developed and tough and strong - not like the rest of me

[Valbrona]

You need "a bit" of bend in your knee when the pedal is at the bottom and your foot level....

Not sure about that. Should it read: You need a bit of bend in your knee when the pedal stroke is furthest away from the rider. So looking at your picture that would be more like 7 o'clock as opposed to six.

[531colin]

You need "a bit" of bend in your knee when the pedal is at the bottom and your foot level....

Not sure about that. Should it read: You need a bit of bend in your knee when the pedal stroke is furthest away from the rider. So looking at your picture that would be more like 7 o'clock as opposed to six.

I think that's why it works best when freewheeling, rather than propped against the wall.....freewheeling the pedal will be furthest away from you....propped against the wall you have to contend with the freewheel ratchet. (freewheeling you may be sat on the saddle better, as well?)
....I'll edit it anyway...

[531colin]

The "bump" as you call it is when the knee "locks out"..................

.....yes, that's easier to write, too.....

[sreten]

My pet theory at the moment is that when I get a "bump" (knee locking out) the saddle is a few millimetres too low, so I raise it until the "bump" goes,
and that's my saddle height. (In fact, I raise the saddle until the "bump" has gone in one leg, and is still there in the other leg, but that's a different matter..... )

Hi,

Set the saddle far too low, or far too high, no lockout on low, lockout inevitable high.
So your pet theory has serious problems.

FWIW I'm quite happy to have different geometries on my two bikes, that suit the bikes.
They are very different, so it is inevitable, but the same would apply to more similar.

IMO trying to make bikes "feel" the same based on one bike is all wrong. Each bike
should be adjusted to feel the best when riding it a lot. Impressions when your
changing bikes IMO are pretty useless, IMO the worst sort of rider feedback.

rgds, sreten.

For "new cyclists" being able to touch the floor from the saddle tends to
be more important than good saddle height, but as you get more serious,
then simply pedalling on your instep locks out your legs, but using the
ball of your foot doesn't. For "new cyclists" its often suggested saddle
height is set by when locking out your legs pedalling on your heels.

[Brucey]

I think I see what you mean, but I guess it all depends how tight your calf muscles are (vs your quads maybe?) even when they are meant to be relaxed.

This in turn may or may not be related to the angle of your foot when you are pedalling normally.

A further complication is that people's knees (and elbows) flex by different amounts. My knees will go 'overcentre' (just) but my elbows won't, and never have done; about 175degrees is about my lot.

cheers

[Tigerbiten]

Doesn't work with me.
I have hypermobility in my knee joints so they don't lock until they are well behind a straight hip-knee-foot line.

To set my seat-pedal distance I just sit on the seat and with a straight leg put my heel on the pedal when it's at it's maximum extension.
That will normally get the distance right to a few mm.
One reason I like the hardshell seat on my bent trike is I don't slip down it like I did on the mesh seat.
So the seat-pedal distance is a lot easier to set right first go.

[531colin]

..............
IMO trying to make bikes "feel" the same based on one bike is all wrong. Each bike
should be adjusted to feel the best when riding it a lot. Impressions when your
changing bikes IMO are pretty useless, IMO the worst sort of rider feedback...................

Well, I couldn't disagree more. I have 5 bikes, all of them variations on the traditional drop bar British tourer.
Changing from one bike to another I notice small differences, which is an opportunity for me to decide if there is something about one bike which I prefer, and if I would like to transfer that feature to another bike or bikes.
Some things are sacrosanct.....crank length is always 170mm, and reach to the pedal is as similar as I can get it.....its a miserable experience setting off on a group 70 mile ride with your saddle 5mm "wrong" compared to the bike you are habituated to at the time.

[531colin]

Please assume I have heard of setting the saddle height by putting heel to pedal. If they would follow that method, several new cyclists of my acquaintance would get a better seat height than they have now. But where do you, the experienced cyclists, go from there?
I can understand if the answer is "I twiddle with it until I feel comfortable"......but there are two problems with that, firstly, that experience is not readily transferable, and secondly you get into Mark's position on this thread http://forum.ctc.org.uk/viewtopic.php?f=5&t=73840&start=300 where a bike fitter has lowered Mark's saddle a lot, and Mark thinks its wrong because its not what he is used to......which is, of course "comfortable" until your knees or back complain.
On a group ride, I can get people to think about their saddle height by comparing them with somebody who has a good fluid pedalling style, for example without pointing their toes and dipping their hips to reach the pedal at the bottom.....but its hard to do that in other situations, like over the internet.
I find advice about forward/back saddle position is readily accepted. Very many people who buy race bikes end up with too much weight on their hands. After a couple of hours riding their wrists and shoulders are getting sore, I can ride next to them and show that I only need one finger on the bars to support my weight, and they can do it too, if they slide back on the saddle. Also, KOPS is fairly readily accepted, possibly because it sounds like something more than a coincidence.
So really, I guess I'm looking for something like KOPS, but for saddle height.
I set my saddle height so that I can ride a good stretch of rocky track pedalling, "seated" but actually allowing the saddle to bounce about under me, so that's maybe a bit lower than just a "road" position..........and most people won't do it anyway.

[samsbike]

I am not sure if I am an experienced cyclist but I ride just below the knee lockout bit, to the extent that I can lock my knee by a very slight movement in the hip. Also on the heel test, my knees are locked out. I know the seat is too high as on my downward pedal stroke I will go toe down, while at just below the knee lockout bit, I can push down with a level foot.

I am pretty sensitive to seat height, where I will notice a 5mm difference.

What is also weird is that by sliding forward on the seat, I feel myself sitting much more in the bike and using the muscles on the top of my thighs. I can tell because they start to hurt if I do it too often. Pushing back is more comfortable at the expense of outright power.

I think I saw a site with what Colin is talking about and will try and find it. Although it was a TT thing.

I think it was this site

http://www.bikesplit.com/bsa3.htm

[andrewjoseph]

Colin, the bump you feel is probably due to your anatomy/muscle tightness. I've never felt it at any time and I have experimented with extreme saddle positions.

I do sometimes get a click in my left knee near bottom of the pedal stroke (but not at greatest extension), if I let my ITB get too tight. A couple of sessions on the foam roller helps to cure it.

[531colin]

Sam, thanks for this......



from http://www.bikesplit.com/bsa3.htm

That's the sort of thing I'm looking for, an easy to explain rule of thumb for setting seat height.
As in my picture at the top of the thread, my saddle is a few millimetres lower than their "ideal" , but I'm happy to accept that as a difference between them wanting maximum power output for an event on the road, and me wanting a comfortable all-day ride, including tracks.

Anybody got any major issues with that?

[Mick F]

Sounds like a check next time out!
Good link, and great diagrams.

[Brucey]

Please assume I have heard of setting the saddle height by putting heel to pedal. If they would follow that method, several new cyclists of my acquaintance would get a better seat height than they have now. But where do you, the experienced cyclists, go from there?....

well I would recommend that by some method (heel on pedal if time is short, a proper body measurement if not) that the saddle is set to the nominally correct height and then like you say that tweaks are made from there.

One method is to have someone try the 'correct' saddle height for a while and then to set it lower by 10mm. When set like this it is normally easy enough to demonstrate that;

a) you are no longer at KOPs (which is admittedly a circular argument) and that
b) when on a draggy climb, you can usually get more power by sliding backwards in the saddle and allowing the leg to extend a little further. If the saddle is really too low then you can be right off the back of it and still making more power, so it is usually obvious when this is the case.

Similarly if the saddle is experimentally set 10mm 'too high' then the hips may be rocking, smooth pedalling at high cadence may be difficult, the toes may be pointed down, and sliding backwards on the saddle instantly sets you too high above the pedals.

Between these two positions most people will find the best spot. If a rider is unconvinced, You can have them look at a willing third party (with a nice riding position), and then by moving that third party's saddle temporarily, show them how it looks and feels when the saddle height is a bit wrong. As per you original post, you can allay any fears concerning 'losing the old position' by making notes or marks on the seat post etc

In the wintertime thick clothes, different shoes and other things (spare tyre, less flexible plastic saddle hull etc) often mean that the saddle position is slightly wrong, even if it was OK in the summertime.

cheers