So it seems that many/most have moved from KOPs for determining saddle fore-aft position, and are favoring balance methods -- getting into a good cycling pace on a trainer and then pulling your arms back, and seeing if you can maintain position without back strain.

My question about this is, isn't this dependent on stem length and other aspects of bike fit? In other words, I thought saddle fore-aft position was the most important aspect of fit, and the first thing you should get dialed in on your bike. But being able to balance after pulling your hands away from the handlebars is dependent on where your hands were in the first place, i.e. the reach from saddle to handlebars, which is dependent on stem length every bit as much as saddle fore-aft.

So how do I know if my problem is that my saddle is too far forward, rather than that my stem is too short (or bike too small)?

My 2cents: disregard the "balance method", because it doesn't have to do with balance. If that balance is important to position in the first place, which is also dubious.

Sit on a stool, hang your feet forward off the ground and try to lean forward. No matter how far your bottom is from where your feet are, you will tip forward if you lean forward. There is no saddle position balance point. That "balance" is how much of the forward weight is taken up by the core muscles (braced by your feet)

My unscientific method is to move the saddle back to the point where I can ride no-handed in a straight line. If the saddle is too far forward, the bike wants to veer to one side or the other when riding with no hands. Next, I install the appropriate stem to put the bars where I want them. I'm looking for comfort on long rides, not maximum speed, so this is what works for me.

Imo, kops is as valid or invalid as that "balance" method. (Which, afaik, is from another voodoo whisperer Steve Hogg).

Right, nothing exist in a vacuum, and stem length and angle and bar angles and etc are all integral to your overall fit and balance on the bike when all points of contacts are active.

The tried and true methods persist, and if they apparently work for millions of people, then it must be for a good reason. It may very well not work for you individually, but it atleast establishes a good starting point.

After long enough rides, and through various terrains and intensity, I'll find whether my body and my ass tends to want to slide forward or push back from existing o baseline position...and I'll adjust base on that

For me, I tend to sit where I sit.

If the saddle is too far forward, I sit on the back part.

If the saddle is to far back, I sit on the skinny part.

Pretty easy for me to set fore/aft.

KOP will help get your leg in the right angle with your pedal. When I got a fitting last year, I would have bet that my leg angle was correct. After my fitter video taped me pedaling on a trainer, he showed that my angle was way off. He moved me to KOP and pedaling magically became more comfortable. He also did the balance test(riding position) to see what length of stem I needed. The first thing to get dialed in is your saddle height. Second is the fore/aft, then your handle bar height and stem length.

Don't think of it as balancing on the saddle in isolation. You have to include the pedals together with the saddle as the fulcrum while pedaling.

Well, if your feet are hanging off the stool,

then knee angle doesn't matter either, so you can have 4cents.

Knee angle is the same regardless of fore/aft; it depends on saddle height

Shirley you jest.

knee angle depends on the distance from your feet to your hips. It will be the same on a recumbent as on a race bike, as long as the distance is the same. Moving the seat back you lower it to maintain the same distance, so the knee angles are the same. The direction of the force vectors will change with respect to vertical, is that what you meant?

Think of it from the other direction- once you have settled on a basic riding position, with arms back you want to

balance, or almost balance. This could be done with no bars on the bike at all. Then stem length is one factor

in how much weight is on the hands.

He's serious. And don't call him Shirley!

Not Shirley and not Jest either, although I realize that both "knee angle" and "balance" are hot-button topics for some reason.

The "balance point" is the place for the seat (actually your hips) where the moment of the forces of your weight and pedaling force add up to zero, meaning there is no weight on your arms. But obviously this "point" only works at one pedaling force. My real question is why weight on your arms or hands is all that bad.

I ride with real weight on my hands most of the time. (Being relatively aero so I can ride upwind relatively comfortably didn't suddenly become less important as I started into my 7th decade. If anything, it became more important.) But it has becoming increasing more obvious also that I have to pay more attention to the actual fit of my hands on the handlebars, esp the angle of my wrist. If that angle is wrong, esp if my wrists are cocked up (hitchhiking and pulling your thumb toward your shoulder) I get hand numbness. The more I rotate my brake levers and handlebars down, the happier my hands are. My setups are with traditional HBs and look like racing setups out of the 60s and 70s. (I look at modern "ergo" bars and brake hoods that are intended to point up like horns and wonder how that works. I need the bottoms of my handlebars and brake hoods to be roughly level.

My practice when setting up a bike is to 1) not tape the HBs (except just enough electrical tape to secure the brake cable housings) and go for a ride with all the HB and brake lever wrenches. Stop and adjust as needed. 2) Wrap the bars with cloth tape because it has enough stick to repeatable un-tape, more levers and re-tape. Not until that tape is worn out do I put on the good stuff.

Of course, I do put my handlebar, brake hood and hand positions to a greater test than most by riding many of these bikes uphill in sometimes very big gears. (A reality of riding fix gears.) I have learned that on real hills, real injuries happen if all is not just right. It sucks when you feel that injury starting and you are only half way up. And back to the issue of "seat balance"., well all of that climbing is out of the saddle and the primary "weigh" on my hands is pulling. The undersides of my brake levers and hoods matter far more than the topsides.

Ben

Funny how easy it really is, and how hard folks try to make it. I always know if a saddle is too far forward or aft, too high or low just as you say. You sit in the right place. The proper thing to do is to put the saddle right there. It has nothing to do with balance or core strength, but only how your legs engage the pedals. That's why you set the saddle with regard to the BB and nothing else.

It is really a lot like adjusting cleat position and angle on shoes. Your foot goes to the angle and position it prefers. All you have to do it tighten the cleat to hold that spot.

Interesting, I go the opposite. If the hoods are down very far then wrists feel out of neutral- especially with more

drop/bent elbows so hoods are cocked up. Not great for standing climbing, but worth it.

I do so much standing climbing that if I don't cater to that first, injuries happen. The rest of the time, I can always ride the drops and just slide higher around the bend. Plus i have always liked the securtiy of the drops. The place to be when I am tired and not at full attention. The place to be when I hit potholes or rocks. (What I didn't say above is that I first choose and set up my bars to be ultimately comfortable in the drops.)

Ben

But wouldn't where you sit on the saddle be dependent on your seated posture (back angle), and isn't that dependent on where the handlebars are?

One thing I've noticed is that if my saddle is too far back, I don't spin as well, fast, smoothly. I'll bounce once I get above 110 rpm. Coincidentally, this is about at KOPS.

your back angle should be set for where you want it to balance fit and aero objectives and seat position and fore-aft balance should be set with this in mind, so not really dependant on the handlebar position, except to adjust the handlebar position to this seat position and back position AFTER setting the fore-aft.

That seems to make sense, but if true you would have to move your saddle when you change your hand position, from the drops to the tops for example. But that is absurd. Hence, your postulate can't be correct.

Thanks, everyone.

Actually moving the saddle like that would be silly, but people do move their seated position on the saddle when they change hand position. If you just lean forward to get more aggressive, the body angles scrunch up: pedaling gets harder, breathing gets harder. If you rotate your entire body forward about the bottom bracket, the angles are preserved and it's easier to drop the hammer while aero. Hence the phrase "on the rivet."

And bikes designed to be always ridden in aggressive postures often have saddle positions that are farther forward. Triathletes happily ignore the UCI rule about saddle noses being at least 5cm behind the bottom bracket, and for UCI-sanctioned TT events, some manufacturers sell saddles with short noses to cheat the rule.

I have the same question. If your bars are lower then you will rotate your hips more to reach them, which in turn will pretty your centre of gravity forward. To achieve balance, you would then need to move your torso to the rear by moving the saddle back (or at least shuffling back on the seat).

So it would seem that the balance is at least somewhat dependent on your bar height and reach.