Cycling UK Forum

I have two bikes that are very similar. One has a Brooks Conquest (leather sprung) saddle, the other a B17.

The B17 bike seems a bit more sprightly than the sprung saddle one. They have different tyres, Supremes and pre Greenguard Marathon Originals, so this will make a bit of difference.

I was thinking about the effect of the springing while out today and have just read a comment on the Brooks vote post about the loss of energy on a sprung saddle. So, is the amount of energy lost with a sprung saddle a factor worth considering. I am fairly light, at about 65kgs and do feel the springs working a bit when riding.

you have the opportunity to 'do some science'....

First, swap the front Marathon onto the rear of the bike with the supremes and replace it with a supreme so that both bikes are similarly shod (supreme at the front, marathon at the rear).

Next, using a pulse meter, once warmed up, time a ride on a circuit at a fixed pulse rate on one of the bikes. That is your 'control condition'.

Now repeat that on the other bike.
Next swap the saddles (set them to the correct height) and repeat.
Finally repeat the control condition.

Do the same on other days, maybe ringing the changes on the sequence.

You will get some data which will tell you if you are affected by the saddle type or not.

cheers

It's surprising how much power is lost through suspension - be it sprung saddles or frame suspension like my Moulton.
I can feel the power absorption, so no doubt you can feel the same with your sprung saddle.

I agree with Brucey's idea, but maybe you just need to time a regular ride over a few trips and take an average. Then swap saddles onto the same bike, and repeat.

I've found that I lose a minute per mile swapping from Mercian to Moulton. Yes, I know they are very different bikes, but the difference in speed/time is marked even though the bikes have the same geometry and ridden by the same bloke wearing the same clobber.

It wouldn't surprise me that a sprung saddle would absorb pedalling power.

Easiest thing is to swap saddles and seat posts form both bikes, and leave every thing else alone.

I've a Brooks Conquest saddle on my shopping bike and it's really comfy. I'm a dyed-in-the-wool Brooks rider but I was perfectly happy with the plastic saddle the bike came with because it was only used for relatively short journeys and could be left in the rain. The Conquest came from a big pile of bargains on the CTC stand at York Rally yonks ago, probably leftovers from the original in-house CTC shop. Knowing how much new leather saddles can vary, I spent some time picking the right one and it's beautifully supple.

Back to the thread title, I think that at leisure speeds there's no significant difference. I think that hammering along, there'd be a tendency to bounce up and down on the saddle which would make pedalling smoothly difficult, and be generally unhelpful, whatever the result of some proper scientific test.

Back to waffling, this is just another example of Brooks being behind the curve, as we trendies say (perhaps that's another curve I'm behind ) Brooks introduced the Pro as a racing saddle - no bagloops - just as racing cyclists were going plastic (Unica Nitor) and generations of tourists for whom the Pro would otherwise be ideal cannot easily fit a saddlebag. The Conquest is labelled MTB. How many mountain bike riders would want a leather saddle? And need I say it, no bagloops.

Last year I was looking for a new saddle and took advantage of free trials that some saddle manufacturers and retailers offer. I tried various Fizik and Prologo offerings and was amazed at the difference a really 'hard' saddle made in terms of power at the cranks. They really felt much faster and appeared to give extra power to each stroke - so I was convinced there was a real difference. In the end I found some NOS of my original saddle which had broken after about 20,000 miles so bought one of those. Improved power transfer comes at the cost of comfort!!

Maximum power gain is achieved by the use of a really narrow, really hard and really rigid unsprung saddle which discourages the rider from sitting down on it at all. A topping of broken glass and barbed wire ensures that the rider does not indulge in surreptitious perching but is obliged to apply full power to the pedals at all times.

Maximum energy loss, on the other hand, is achieved by the use of a saddle having the most elaborate and compliant springs available, making the rider so comfortable that pedalling becomes more of an inconvenience to be avoided than an aim to be pursued.

The energy loss is minimal because springs return most of the energy put in but the feel is very different.

In theory, yes.

In practice, when you push with the power-stroke, some of the energy is subtracted.
The "return" springs may help you lift your foot upwards, but it doesn't push the other foot downwards.

Basically, you bounce up and down in sync with your cadence, but the up doesn't help the down.

Try a parallelogram suspension seatpost instead. I've been gobsmacked by the improvement in comfort since fitting a Suntour NCX seatpost to my Thorn Audax - and I don't perceive any loss of power.

Mick F wrote:In theory, yes.

In practice, when you push with the power-stroke, some of the energy is subtracted.
The "return" springs may help you lift your foot upwards, but it doesn't push the other foot downwards.

Basically, you bounce up and down in sync with your cadence, but the up doesn't help the down.

When you push down a pedal, you initially reduce the pressure in the saddle and the spring expands, then gets compressed as you get further into the stroke. You bounce a bit during extreme efforts but it's very close to net zero, possibly unless your saddle is too high and only oscillating below rest instead of around it.

No one has mentioned the sprung ones are rather heavy?

mercalia wrote:No one has mentioned the sprung ones are rather heavy?

Only by a few grams of spring on each side.

Unless it's Brooks who seem to think you don't care about weight if you want springs.

mjr wrote:

Mick F wrote:In theory, yes.

In practice, when you push with the power-stroke, some of the energy is subtracted.
The "return" springs may help you lift your foot upwards, but it doesn't push the other foot downwards.

Basically, you bounce up and down in sync with your cadence, but the up doesn't help the down.

When you push down a pedal, you initially reduce the pressure in the saddle and the spring expands, then gets compressed as you get further into the stroke. You bounce a bit during extreme efforts but it's very close to net zero, possibly unless your saddle is too high and only oscillating below rest instead of around it.

You're going to tell me next that riding in a hilly area works out the same as a flat area?

Climb a hill and get a free ride down the other side?
Same as flat?

No. Flat is clearly harder because you never get a rest unless you stop.