Saddle height: The deciding factor?

[Stefan Mikes]

For a few years since I started riding e-bikes I had 72 cm memorized as my "saddle height" (the distance measured from the centre of the bottom bracket or rather the mid-drive motor spindle in the straight line along the seatpost to the surface of the saddle). Once, I took a Specialized pedal bike for the test ride; the LBS mechanic set the saddle a tad too high. Unawares, I completed a rather short ride (some 34 km) devastated.

The years were passing by and eventually I discovered my optimum saddle height dropped to 69 cm. OK, I had it set on my two e-bikes since; it is natural for a human being to shrink in the old age.
------------
On my latest ride, I managed to raise the saddle "a little, by feeling". It turned a nice ride into a disaster: I was pedalling inefficiently and my groins hurt. After the return, I dropped the saddle on that e-bike (Vado SL) to the original height and the situation went back to normal. Or, I thought so: I still had a feeling I was slightly hanging on the saddle. Testing the saddle height by usual methods. For instance, put your heel on the pedal and rotate the crank so the leg is fully extended. It all seemed normal.

I gave this Saddle Height Calculator a try. The results produced a ridiculously low saddle height values. I tried the LeMond method: measure your barefoot inseam in cm and multiply by 0.883. That also gave the lower saddle height but not as low as the calculator.

So I dropped the saddle by 1 cm/10 mm (it is a big deal). The outcome: I feel low on the e-bike. Nothing dramatic but I must have got used to the previous setup. No gain on the measured leg power. Only I realised the saddle pressure on my butt has decreased.

I feel helpless... Opinions? Experiences?

 

[mrgold35]

I have to go by feel for my seat height (mainly any left knee pain when my saddle is to low).

I usually factor in:
- shoe stiffness and thickness
- padded shorts
- saddle type and thickness (cloud-9 cruiser seat with springs)
- stem length (350mm is too short and need +400mm)
- suspension seatpost float (switched from NCX SP-12 to Kinect Bodyfloat)
- handlebar height
- knee position on down stroke

 

[PedalUma]

I like the heal, toe method. On the saddle with the pedal fully extended and the heal on the pedal, the knee should be straight and locked. And when the ball of the foot is on the pedal the knee should be slightly bent. @mrgold35 is correct in mentioning footwear. I generally prefer shoes that are thin, comfortable, and flexible with grippy platform pedals. That way I can pull back and up without clipping in, so I am ready for walking at my destination. Cycling is about getting somewhere and what you are doing when you arrive.

 

[Cycologist]

It's interesting how the smallest changes can make a big difference.

I use a goniometer to measure leg angle and adjusted my seat accordingly. Then I got a new pair of biking shoes and started having knee pain.
Turns out the new shoes changed something and I had to raise the seat 1 cm, which corrected the issue.

I'm still battling seat height, angle and forward / back position. I can't seem to get it right and probably need to go to a bike fitter.

 

[BEC111]

For a few years since I started riding e-bikes I had 72 cm memorized as my "saddle height" (the distance measured from the centre of the bottom bracket or rather the mid-drive motor spindle in the straight line along the seatpost to the surface of the saddle). Once, I took a Specialized pedal bike for the test ride; the LBS mechanic set the saddle tad too high. Unawares, I completed a rather short ride (some 34 km) devastated.

The years were passing by and eventually I discovered my optimum saddle height dropped to 69 cm. OK, I had it set on my two e-bikes since; it is natural for a human being to shrink in the old age.
------------
On my latest ride, I managed to raise the saddle "a little, by feeling". It turned a nice ride into a disaster: I was pedalling inefficiently and my groins hurt. After the return, I dropped the saddle on that e-bike (Vado SL) to the original height and the situation went back to normal. Or, I thought so: I still had a feeling I was slightly hanging on the saddle. Testing the saddle height by usual methods. For instance, put your heel on the pedal and rotate the crank so the leg is fully extended. It all seemed normal.

I gave this Saddle Height Calculator a try. The results produced a ridiculously low saddle height values. I tried the LeMond method: measure your barefoot inseam in cm and multiply by 0.883. That also gave the lower saddle height but not as low as the calculator.

So I dropped the saddle by 1 cm/10 mm (it is a big deal). The outcome: I feel low on the e-bike. Nothing dramatic but I must have got used to the previous setup. No gain on the measured leg power. Only I realised the saddle pressure on my butt has decreased.

I feel helpless... Opinions? Experiences?

I’m puttering in the same playground with my new bike. I’m using the same suspension seat post that I had on the SL1 but the initial setup has the saddle at a much lower position according to the measurement marks on the seatpost. It’s been dangerously hot and now extremely dangerous Canadian wild fire smoke have prevented my riding this week so I can’t do additional saddle height tweaking. (Minor, but fun advantage to the SL2 - the new bike uses a more conventional clamp. No more saddle post wedge falling into the frame!)

 

[6zfshdb]

When it comes to saddles, posts and their adjustments, everyone has different requirements for a "comfortable" ride. From personal experience, I've found age has a lot to do with this. In my younger years, I would adjust the seat height so my leg was absolutely straight on the downstroke. This gave me the most efficient and comfortable ride. The down side was, I would have to slide forward off the seat when stopping to get my feet on the ground. No big deal for a younger person.

For me to do this now is a risk because my balance isn't what it used to be. At this point, I prefer to lower the seat to where I can touch the ground with my toes on both sides while my butt is still on the saddle when stopping. This means my leg is slightly bent on the downstroke, which results in a loss of efficiency. However, the e-bike easily compensates for this loss. I do sacrifice some seat comfort doing this, but to me anyway, the tradeoff is worth it.

Just my experience though, so YMMV.

 

[PedalUma]

When it comes to saddles, posts and their adjustments, everyone has different requirements for a "comfortable" ride. From personal experience, I've found age has a lot to do with this. In my younger years, I would adjust the seat height so my leg was absolutely straight on the downstroke. This gave me the most efficient and comfortable ride. The down side was, I would have to slide forward off the seat when stopping to get my feet on the ground. No big deal for a younger person.

For me to do this now is a risk because my balance isn't what it used to be. At this point, I prefer to lower the seat to where I can touch the ground with my toes on both sides while my butt is still on the saddle when stopping. This means my leg is slightly bent on the downstroke, which results in a loss of efficiency. However, the e-bike easily compensates for this loss. I do sacrifice some seat comfort doing this, but to me anyway, the tradeoff is worth it.

Just my experience though, so YMMV.

@6zfshdb, You may like a foot forward bike. They are super comfortable. You can get full leg extension and still place your feet on the ground. Putting a mid-drive on a Specialized Roll does this. You are upright and it has a lax geometry. The wheel base is also long for stability. It can come in a low entry model. See the angle of the seat tube? That lowers the distance to the ground. But full leg extension is a bit more like a semi-recumbent with the foot forward. Race bikes have a nearly vertical seat tube. And they have twitchy handling. Note the distance from the bb to the rear tire and the rake of the fork. Just like a longer boat better handles choppy seas, this bike give a smoother ride.