Is saving weight worth the bother?

littledove44

Man and bike weigh 100kg say.
Reduce bike weight by 1kg without changing the aerodynamic profile.
So we have reduced weight by 1%.

Assuming nothing else changes, the same power input from your legs should increase your speed by 1% (actually a little less because some of the increased power is consumed by increased drag of the higher new speed)

So, on a 3 hour ride I will save 1.8 minutes.
Important if you are racing, but irrelevant otherwise.

Is this fundamentally incorrect?

simon_masterson

All other things being equal, yes, but can you complete that distance consistently (however far you rode in 3 hours) to that level of precision, or might it fluctuate by 1.8 minutes or more?

The principal fact of this matter is that weight is decidedly secondary to aerodynamics. Not very important at all. You really can't buy a 'heavy' road bike as it is, but as bikes and components get better, they generally get lighter anyway. Whether it's made of carbon fibre, aluminium or steel, a bike can weigh less than 8kg.

Apart from the handling of the bike, weight comes into play when climbing steep hills, particularly for lengthy durations, but that relies on all things being equal; in the case of amateur cycling, they seldom are. For racing cyclists in peak condition that produce peak performance consistently (and have little excess body weight), reducing the weight of the bicycle that they will race up the mountain on will produce quantifiable benefit; not that they would use a 9kg bike anyway.

In terms of your money, it depends on how much weight and how much is being spent. 200g in isolation is a waste of time and money, but 5 increments of that weight or more (though you might be surprised at how difficult this can be) would make a noticeable difference.

♠ChumBucket♠

You'd probably get more than that 1.8 minutes back by the extra 1KG on the descents!

Interestingly, I was watching cycling on Eurosport the other day. Approx half a dozen riders on a descent, the leader off his seat sat on the top bar, everything tucked in to the max & to be honest- looking an idiot!! The other 5 behind him just sat in normal position, looking relaxed & probably taking the opportunity to recover a little. Anyhow, for all his acrobatics, the leader got no further in front whatsoever, didn't increase the gap at all. so, what's the point of all that then?? Aero my backend!!

Then, also on the same prog', I was watching some of the riders with their shirts both partially open (causing drag) & fully open (causing drag & turbulence) . Then I thought, this team have probably spent untold amounts both monetary & R&D on aero, weight saving etc.

So, are many of the extreme cycling aspects worth the bother, or is it just for the placebo effect??

I know what I think!!

rolf_f

♠ChumBucket♠ wrote:

You'd probably get more than that 1.8 minutes back by the extra 1KG on the descents!

You certainly wouldn't. Time saved climbing is never offset by time lost descending. A 15 minute climb will probably take 3 minutes to get back down. You might save a minute or two on the climb but you are hardly going to equal that or more on a 3 minute descent.

♠ChumBucket♠ wrote:

Interestingly, I was watching cycling on Eurosport the other day. Approx half a dozen riders on a descent, the leader off his seat sat on the top bar, everything tucked in to the max & to be honest- looking an idiot!! The other 5 behind him just sat in normal position, looking relaxed & probably taking the opportunity to recover a little. Anyhow, for all his acrobatics, the leader got no further in front whatsoever, didn't increase the gap at all. so, what's the point of all that then?? Aero my backend!!

Yes, the other riders were behind him. They don't have to tuck in so much as they benefit from the aero of the rider in front. The faster the bloke at the front, the faster the group as a whole. Sitting on the top bar does increase your speed. And the bloke at the front wasn't actually trying to increase his gap over the little group with him - just the main peloton further back. I think you need to read up on cycle racing a bit - it's more complicated than you seem to think!

charlie_potatoes

Someones done a few sums here FWIW.

https://www.youtube.com/watch?v=5DRQwKREgvI

♠ChumBucket♠

Rolf F wrote:

♠ChumBucket♠ wrote:

You'd probably get more than that 1.8 minutes back by the extra 1KG on the descents!

You certainly wouldn't. Time saved climbing is never offset by time lost descending. A 15 minute climb will probably take 3 minutes to get back down. You might save a minute or two on the climb but you are hardly going to equal that or more on a 3 minute descent.

♠ChumBucket♠ wrote:

Interestingly, I was watching cycling on Eurosport the other day. Approx half a dozen riders on a descent, the leader off his seat sat on the top bar, everything tucked in to the max & to be honest- looking an idiot!! The other 5 behind him just sat in normal position, looking relaxed & probably taking the opportunity to recover a little. Anyhow, for all his acrobatics, the leader got no further in front whatsoever, didn't increase the gap at all. so, what's the point of all that then?? Aero my backend!!

Yes, the other riders were behind him. They don't have to tuck in so much as they benefit from the aero of the rider in front. The faster the bloke at the front, the faster the group as a whole. Sitting on the top bar does increase your speed. And the bloke at the front wasn't actually trying to increase his gap over the little group with him - just the main peloton further back. I think you need to read up on cycle racing a bit - it's more complicated than you seem to think!

What complete nonsense, the lead rider was far enough in front to break the tow, the riders behind him were not, in any way benefiting from any slip!!! It was funny, made a complete mockery of what he thought he was achieving & he looked a total arse to boot!!

Maybe he should have shaved his legs that morning eh? :roll:

ianspeare

If there was a headwind, you could end up 1.8 minutes slower. There's a lot of factors that come in to play. I'm guessing that the jerseys were open on an uphill, where the effect of drag is less due to the slower speed. This is also why people attack more on the hills.

rolf_f

♠ChumBucket♠ wrote:

What complete nonsense, the lead rider was far enough in front to break the tow, the riders behind him were not, in any way benefiting from any slip!!! It was funny, made a complete mockery of what he thought he was achieving & he looked a total ars* to boot!!

OK - I'll bite. How far ahead was he and why would he have wanted to break the tow in the first place?

Seriously - I think you should post this in Pro Race if you really want to understand what was going on. Unless you genuinely think you know more about how to win a cycle race than a professional rider.

♠ChumBucket♠

The point is Rolf- not how or why, but the fact that he was NOT benefitting whatsoever from his "aero acrobatics". Infact, he would have probably cost himself more in energy loss!

I suppose you be out this aft' with shaved legs pulling up on the pedals?? :roll:

I'm not led by anything or anyone, unlike "pro's" like yourself.

♠ChumBucket♠

Oh, I also have a fantastic ability to smell bullpoop!!

rolf_f

♠ChumBucket♠ wrote:

The point is Rolf- not how or why, but the fact that he was NOT benefitting whatsoever from his "aero acrobatics". Infact, he would have probably cost himself more in energy loss!

If he had sat up, then the whole group of riders he was in would have been going less quickly. That would give the following group an opportunity to gain time. He would have had no interest in getting away from the riders in his group because, riding on his own, he would be at a disadvantage over them as five riders will move more quickly than one.

FWIW, I have tried riding in that position and it certainly does result in a speed increase though it isn't a position you'd want to use if there was a risk of hitting a pothole.

Fact is that it is a standard, commonly used position in racing - if it didn't work, people wouldn't use it. Or if you really do know something, give Dave Brailsford a call as he'd be really keen to learn from you!

♠ChumBucket♠ wrote:

Oh, I also have a fantastic ability to smell bullpoop!!

You are confusing the ability to smell with the ability to talk. But go on, if you are so sure of yourself, post a thread in Pro race. I dare you! I'm happy to be proved wrong by folk who know more than me but that isn't you!

robbo2011

♠ChumBucket♠ wrote:

Oh, I also have a fantastic ability to smell bullpoop!!

Err, you don't, actually.

♠ChumBucket♠

Rolf F wrote:

♠ChumBucket♠ wrote:

The point is Rolf- not how or why, but the fact that he was NOT benefitting whatsoever from his "aero acrobatics". Infact, he would have probably cost himself more in energy loss!

If he had sat up, then the whole group of riders he was in would have been going less quickly. That would give the following group an opportunity to gain time. He would have had no interest in getting away from the riders in his group because, riding on his own, he would be at a disadvantage over them as five riders will move more quickly than one.

FWIW, I have tried riding in that position and it certainly does result in a speed increase though it isn't a position you'd want to use if there was a risk of hitting a pothole.

Fact is that it is a standard, commonly used position in racing - if it didn't work, people wouldn't use it. Or if you really do know something, give Dave Brailsford a call as he'd be really keen to learn from you!

♠ChumBucket♠ wrote:

Oh, I also have a fantastic ability to smell bullpoop!!

You are confusing the ability to smell with the ability to talk. But go on, if you are so sure of yourself, post a thread in Pro race. I dare you! I'm happy to be proved wrong by folk who know more than me but that isn't you!

It was mid-pack, a small group that had broke away, not the back, not the front, just a few "also rans" He was in front of this small pack by about 15/20 bike lengths, there was ZERO drag being offered by him, the riders behind WERE NOT in a position to to obtain any slip because of this distance between them- IS THAT BIT CLEAR ROLF??????

He was sat on the top bar, curled up like some tit who'd been reading cycling forums & the others behind (still not close enough to be in the drag, got that Rolf?) were just casually in the normal position, on the seat, quite chilled, it didn't appear they were making any effort to catch him at this point, the gap remained the same (got that bit Rolf?) just incase- THE GAP REMAINED THE SAME!! The tit sat on his top bar didn't make any time i.e. the others who were not sat on the top bar went just as fast sat in their normal positions.

The point is- in this instance for sure, the guy in front, sat on his bar looking a total spam, gained NOTHING for it- whether he wanted or not doesn't matter, his "super aero" position proved fruitless!! that's the point!

robbo2011

Yes, but what you are saying is bullshit.

I don't know where you ride, but perhaps you don't ride many descents.

I ride in a hilly area with long descents and its very clear from my descent times and speeds that if you go into a lower aero position, your speed picks up more than in a normal position. Indeed, when I am on a fast descent and want to slow down, I sit more upright, the wind resistance is noticeable higher and speeds drop.

This is so basic, I can't believe we are discussing this. I know it is road beginners, but even so....

♠ChumBucket♠

OK, I'm blind, I must have lost the ability to see TV pictures!! :roll: :roll:

I'll go for a spin, pulling upstrokes only of course! (like the pro's, NOT)!! lol

dennisn

I don't believe that weight will make a SIGNIFICANT difference IF(big IF) you're buying decent parts, wheels, and frame, no matter what the brand. The idea that you're going to produce big racing or riding results by simply buying stuff that is lightweight has been around forever, i.e. weight weenies.
I attend a lot of local and regional races and have never seen a, so called, weight weenie bike and rider ever really appear in a race, let alone actually be competitive.
Most guys who race well buy good to excellent equipment, depending on their income, but don't obsess over weight of parts, frames, or wheels. They concern themselves with what's really important - conditioning.

rolf_f

♠ChumBucket♠ wrote:

It was mid-pack, a small group that had broke away, not the back, not the front, just a few "also rans" He was in front of this small pack by about 15/20 bike lengths, there was ZERO drag being offered by him, the riders behind WERE NOT in a position to to obtain any slip because of this distance between them- IS THAT BIT CLEAR ROLF?????? [/b]

Well, no - it's not clear actually because before you said he was the leader of a group. If you change the story as you go along, nothing tends to be clear.

♠ChumBucket♠ wrote:

Approx half a dozen riders on a descent, the leader off his seat sat on the top bar, everything tucked in to the max & to be honest- looking an idiot!!

So what you are saying is that a bloke on his own, in the aero tuck, was no faster than a group. A group being aerodynamically more efficient than a single person. And never mind all the variables (eg that I seem to roll faster than a friend of mine, of similar weight to me, on similar weight bikes and in the same riding position - the only obvious difference that I can think being the really fat carbon spokes on his Mavic wheels - leading to an obvious conclusion that he might roll as quickly as me in a more aero position than me).

Do you honestly believe that reducing your frontal area has no impact on aerodynamics? Is a lorry as aerodynamically efficient as a sports car?

And really, there is no need to shout. It makes you come across as a bit deranged

♠ChumBucket♠

Read Rolf, read. I explain it very well.

I know what I saw, do I care enough to sit here all night to convince you? NO! :roll:

♠ChumBucket♠

robbo2011 wrote:

Yes, but what you are saying is bullshit.

I don't know where you ride, but perhaps you don't ride many descents.

I ride in a hilly area with long descents and its very clear from my descent times and speeds that if you go into a lower aero position, your speed picks up more than in a normal position. Indeed, when I am on a fast descent and want to slow down, I sit more upright, the wind resistance is noticeable higher and speeds drop.

This is so basic, I can't believe we are discussing this. I know it is road beginners, but even so....

Who said anything about being sat up? it's drops Vs frame sitting here, not anyone sitting upright.

Anonymous

♠ChumBucket♠ wrote:

Read Rolf, read. I explain it very well.

I know what I saw, do I care enough to sit here all night to convince you? NO! :roll:

You've explained nothing clearly, you've changed your story. If getting down low doesn't make difference then why do they use different tt bikes and positions

robbo2011

Stop clutching at straws. I meant straightening the arms to get back to a normal drop handlebar position from head right down by the bars aero position. You'd have to be a fool to take your hands of the bars and change position at 40mph+

You obviously have no experience of any of this...

♠ChumBucket♠

sjmclean wrote:

♠ChumBucket♠ wrote:

Read Rolf, read. I explain it very well.

I know what I saw, do I care enough to sit here all night to convince you? NO! :roll:

You've explained nothing clearly, you've changed your story. If getting down low doesn't make difference then why do they use different tt bikes and positions

Can you read & do you know what a "normal" descending position is- or could you guess given that one of them is sat on the frame?

If you can, then what's your problem understanding what is written, & also, where have I changed the story exactly?

napoleond

♠ChumBucket♠ wrote:

sjmclean wrote:

♠ChumBucket♠ wrote:

Read Rolf, read. I explain it very well.

I know what I saw, do I care enough to sit here all night to convince you? NO! :roll:

You've explained nothing clearly, you've changed your story. If getting down low doesn't make difference then why do they use different tt bikes and positions

Can you read & do you know what a "normal" descending position is- or could you guess given that one of them is sat on the frame?

If you can, then what's your problem understanding what is written, & also, where have I changed the story exactly?

♠ChumBucket♠

NapoleonD wrote:

♠ChumBucket♠ wrote:

sjmclean wrote:

♠ChumBucket♠ wrote:

Read Rolf, read. I explain it very well.

I know what I saw, do I care enough to sit here all night to convince you? NO! :roll:

You've explained nothing clearly, you've changed your story. If getting down low doesn't make difference then why do they use different tt bikes and positions

Can you read & do you know what a "normal" descending position is- or could you guess given that one of them is sat on the frame?

If you can, then what's your problem understanding what is written, & also, where have I changed the story exactly?

cougie

♠ChumBucket♠ wrote:

You'd probably get more than that 1.8 minutes back by the extra 1KG on the descents!

Interestingly, I was watching cycling on Eurosport the other day. Approx half a dozen riders on a descent, the leader off his seat sat on the top bar, everything tucked in to the max & to be honest- looking an idiot!! The other 5 behind him just sat in normal position, looking relaxed & probably taking the opportunity to recover a little. Anyhow, for all his acrobatics, the leader got no further in front whatsoever, didn't increase the gap at all. so, what's the point of all that then?? Aero my backend!!

So, are many of the extreme cycling aspects worth the bother, or is it just for the placebo effect??

I know what I think!!

I think you need to ride with some others. Get one person to tuck down low and you stay upright on the bars on a descent. It's not placebo at all - its demonstrable on any descent of any length.

No idea which clip you are talking about - but if the aero dude wasnt going away - the others must have been expending energy to keep up their speed.

♠ChumBucket♠

cougie wrote:

♠ChumBucket♠ wrote:

You'd probably get more than that 1.8 minutes back by the extra 1KG on the descents!

Interestingly, I was watching cycling on Eurosport the other day. Approx half a dozen riders on a descent, the leader off his seat sat on the top bar, everything tucked in to the max & to be honest- looking an idiot!! The other 5 behind him just sat in normal position, looking relaxed & probably taking the opportunity to recover a little. Anyhow, for all his acrobatics, the leader got no further in front whatsoever, didn't increase the gap at all. so, what's the point of all that then?? Aero my backend!!

So, are many of the extreme cycling aspects worth the bother, or is it just for the placebo effect??

I know what I think!!

I think you need to ride with some others. Get one person to tuck down low and you stay upright on the bars on a descent. It's not placebo at all - its demonstrable on any descent of any length.

No idea which clip you are talking about - but if the aero dude wasnt going away - the others must have been expending energy to keep up their speed.

The others were not sat upright, they were on the drops- (normal position you would expect given the circumstances). The guy in front was in some ridiculous, cramped up curl, sat on his top frame bar & for all his effort was gaining nothing on the others but must have been highly uncomfortable.

Why do people have difficulty understanding this??

me-109

But was the curled-up guy going quicker than himself in an unfurled position? Never mind the others - himself. Would he have been slower if he was sat up, than in his tucked position? Only the wind tunnel will give you that data and, even then, out on real roads you have to trade aero with control and visibility.

robbo2011

Chumbucket, we don't have trouble understanding what you are saying. The problem is, that your contention that someone in an aero position is no faster than when they are in a normal position is plain and simply wrong.

It's an obvious and demonstrable point. find a few long descents and try it yourself, you'll soon see.

DavidJB

Lol at Chumbucket...absolutely clueless.

♠ChumBucket♠

DavidJB wrote:

Lol at Chumbucket...absolutely clueless.

Lol- just not a sheep!

The lack of any extra aero, over & above the others was clearly demonstrated!

♠ChumBucket♠

Me-109 wrote:

But was the curled-up guy going quicker than himself in an unfurled position? Never mind the others - himself. Would he have been slower if he was sat up, than in his tucked position? Only the wind tunnel will give you that data and, even then, out on real roads you have to trade aero with control and visibility.

Given that they were all professional riders, on professional equipment & assuming of similar ability- he gained no advantage over the other riders in that little group. So, I would say no, he wasn't any faster than he would have been not sat on the top bar. Why, we could argue about forever- lack of control/comfort/visibility etc etc. but the fact remains- he wasn't.