Do those millimetres make a difference?

Beasty

A discussion that started off in Images of Beauty got me to thinking about whether a few millimetres here and there make that much difference to someone like me.

I have no doubt that at the professional level, every millimetre (be it crank length, tyre width, saddle position) can make a material difference. The GB track cycling team, for example, work on the “sum of the parts” principle. Essentially they try and gain every possible advantage, however small, on the basis that the aggregate of all the small things may make the difference between a gold and silver medal. I fully accept that this does make a difference. Bringing it down to it’s simplest level, if a 10mm adjustment makes a noticeable (and measurable) difference then a reasonable estimate of the difference a 1mm adjustment would make would be 10% of the 10mm adjustment (such a linear relationship is probably a reasonalbe estimate when talking about relatively small amounts). I would also say that I think there is a bit of psychology going on with Team GB – if the riders believe they have better equipment, it gives them a psychological advantage over there opponents.

I guess my question is should I really care about the odd millimetre here or there (providing I am comfortable when riding)? I am not going to win any races (because I am not going to enter any – at my age, and with my health history, the last thing I want to do is further increase my risk of crashing!). I may try the odd TT, but by and large the only person I am competing against is myself. As it says on the tin, I am looking to get fitter, and go faster and further than I have done previously. Should I really care too much about marginal adjustments? The simplest and most effective thing I could probably do is lose 5kg of excess body weight (I am officially 10kg overweight, but I think I can justify at least 5kg of that because of my body shape and muscle mass).

What do others think? Do those millimetres (and grams) make that much difference? If so, what measurements are most critical to improving performance (surely there is little point saving 500g of bike weight if I am already carrying 5kg of excess body weight, and stuffing my saddle bag and pockets full of things I won’t need). Then how do I measure what impact those minor adjustments make? There are so many external factors that will influence performance (weather, road conditions, temperature etc). Is it really a matter of “feel” or are you able to see tangible differences that you can put down to the changes?

blorg

Whenever I've changed, say, the stem by 10mm, it does seem to make a big difference- in how the bike feels.

If you are comfortable on your bike and don't have any problems though I wouldn't worry too much about it- especially if you are not racing.

My current position and component lengths is purely through trial and error and tweaking.

Raam

I used not to care about weight of bike/components. Then last night I found myself browsing for deep section wheels and being surprised that the lower end models are all heavier than my Ksyrium SL wheelset. Lower end means from 800 to 1300 by my reckoning. It's kinda put me off the Carbone SL wheelset I had been looking at.

As for bike set up, I've found a set up which seems to work, so presumably you have too. Just stick with that. Saddle fore/aft: I'm not entirely bothered with it, nor with saddle height. Once I'm comfortable, I'm happy.

Ryaner

Raam wrote: »

I used not to care about weight of bike/components. Then last night I found myself browsing for deep section wheels and being surprised that the lower end models are all heavier than my Ksyrium SL wheelset. Lower end means from 800 to 1300 by my reckoning. It's kinda put me off the Carbone SL wheelset I had been looking at.

There is enough studies out there to show that unless the whole route is > 8% or you are very slow, the deep section rims with be faster even though they are heavier. That is why I'm hoping to put the Cosmic Carbone SL wheels on the bike I'm building for the Marmotte next year.

niceonetom

If you're not competing against others then your only metric is yourself. And so the question becomes: does it matter to you?

If you're comfortable on the bike, and you feel efficient and aren't bringing any injury on yourself, then your position is probably ok. It may benefit from some tweaking, but not much more. I raised my saddle a couple of weeks ago by about 2mm. And I can really feel it. It might sound like princess and the pea stuff but, even if it's psychosomatic, it makes a real difference to me. Small changes and trial and error can allow a good set-up to evolve in a way that a session with a plumb-line and motion analysis equipment can't replicate. IMO.

Any little effect a change in set-up, equipment, or weight has is only really perceptible everything-else-being-equal. But everything-else is never equal, so it's impossible to quantify gains and losses in the real world in anything other than subjective terms unless the change is truly drastic (or you work in the marketing department of a bike manufacturer). That means listening to your body and going on feel. I'd leave detailed data analysis to the racers.

Equipment is a whole other thing, but I refuse to believe that it is possible to spend your way to being fast. It's about the engine. If spending makes you build a better engine then so be it. It's fun too.

You will be faster if you're lighter though. All other things being equal :P.

Lumen

Beasty, what sort of position/equipment will you be using for your "40K in an hour" track attempt?

To me "the sum of the parts" makes sense, balanced with "everything in moderation" and "you suck anyway".

Bike position is probably the one thing worth sorting out, particularly for TTing. Given the amount I've spent on my weight weenie bike, I found the IrishFit session yesterday excellent value (for about the cost of a decent stem). But then I'm pretty new to cycling, so YMMV.

As for weight: drop it, fattie. :pac:

blorg

Ryaner wrote: »

There is enough studies out there to show that unless the whole route is > 8% or you are very slow, the deep section rims with be faster even though they are heavier. That is why I'm hoping to put the Cosmic Carbone SL wheels on the bike I'm building for the Marmotte next year.

I honestly wouldn't bother with deep section wheels for the Marmotte. Go with as light as possible in a clincher. Much of it IS >8%, the descents you will be limited by your cornering skill not your wheelset, and the flat bits* you will be in a group.

*There aren't many of them BTW.

Lumen

niceonetom wrote: »

Equipment is a whole other thing, but I refuse to believe that it is possible to spend your way to being fast. It's about the engine. If spending makes you build a better engine then so be it. It's fun too.

You (I) can spend your (my) way to being faster, but it obviously won't get you (me) very far.

Non-equipment things I'd like to spend money on:

- A physical therapist to come round to my house and fix me every few days.
- Wind tunnel testing.
- A DXA test.
- A bigger house with a dedicated room for my bikes, one of those ergometers that measures pedalling efficiency, a treadmill and some weights.
- A coach, and someone to drive me to races in it.
- A pointy hat, 404/808 front wheel options, and a powertapped Zipp sub-9 disc. Or maybe just Cancellara's bike.

OK, I lied about the non-equipment bit.

edit: oh yeah, and a chef.

rottenhat

blorg wrote: »

Whenever I've changed, say, the stem by 10mm, it does seem to make a big difference- in how the bike feels.

10mm is a fairly significant proportion of the length of a stem (and by extension, the lever you're using to steer the bike) though, so I'd see it as likely to make a much bigger difference than 10mm of saddle height where you're maybe talking about 10mm out of the approximately 750mm (on my bike) between saddle and crank spindle. Even so, I have found a 10mm shift in saddle height quite noticeable.

Beasty

Lumen wrote: »

Beasty, what sort of position/equipment will you be using for your "40K in an hour" track attempt?

To me "the sum of the parts" makes sense, balanced with "everything in moderation" and "you suck anyway".

Bike position is probably the one thing worth sorting out, particularly for TTing. Given the amount I've spent on my weight weenie bike, I found the IrishFit session yesterday excellent value (for about the cost of a decent stem). But then I'm pretty new to cycling, so YMMV.

As for weight: drop it, fattie. :pac:

I use the bikes provided by Manchester velodrome (which are decent quality Dolan carbon frames, but the only thing you can adjust is seat height). I am trying to use the drops more, as I realise I my normal position is just about as unaerodynamic as you can get (particularly as I have relatively short legs and a long torso). Hiowever I am also thinking that if I can keep up my current (track) pace without resorting to the drops, there must be more to come.

At some stage I may get a track bike, particularly if I start going to Sundrive. However I would not want to transport it over to Manchester every month (although one option might be to leave it at the in-laws over the winter)

An interesting experience I had with the track bikes - I normally order a 22.5 or 23" frame. One time I got up on the track and was merrily riding along for 10-15 minutes when I was called off by the coach, who pointed out the bike was way too small for me. It was probably 21". I had noticed my knees were getting close to the handlebars, but other than that, I really did not notice too much difference in performance!

I think getting a bike fit probably will give me a much better idea of what difference relatively minor tweaks can make. It's one of those things I think I would like to get done, but never quite get round to (like a VO2 test).

In terms of my weight, I have already set myself the target of losing a few kilos in the "2010 target weight" thread:)

Ryaner

blorg wrote: »

I honestly wouldn't bother with deep section wheels for the Marmotte. Go with as light as possible in a clincher. Much of it IS >8%, the descents you will be limited by your cornering skill not your wheelset, and the flat bits* you will be in a group.

*There aren't many of them BTW.

My choice of wheels when the event comes around will be Open Pros or Cosmic Carbons. The Cosmics are a much better fit for Irish roads since we don't have hills and they aren't much heavier than my current Open Pros.

Also, I hope to be climbing at 12-14km/h by the time the Marmotte rolls around. (Hopefully I know) But @ 8%, the aero wheels should win out compared to a non aero set that are 400g lighter. The set is 1900g including powertap hub.

Raam

Ryaner wrote: »

But @ 8%, the aero wheels should win out compared to a non aero set that are 400g lighter. The set is 1900g including powertap hub.

Hmm, dubious about that one. I think I'd prefer lighter wheels if I was to be climbing half the day.

niceonetom

Raam wrote: »

Hmm, dubious about that one. I think I'd prefer lighter wheels if I was to be climbing half the day.

I share your scepticism. On the marmotte I'll probably be climbing for at least three quarters of the day. The rest of the time I'll be enjoying myself.

Is there really any significant aero advantage from deep rims at 12kph (and that's a pretty ambitious speed to sustain on a climb like the Gallibier btw. 10 is more likely)? Surely weight has to come first? 400g is not nothing...

Lumen, you're our go-to-guy on matters like this. Care to weigh in?

Lumen

niceonetom wrote: »

Lumen, you're our go-to-guy on matters like this. Care to weigh in?

Heavier wheels help you climb faster, because their rotational inertia provides a more stable pedalling platform which makes optimal rpms easier to sustain, biomechanically speaking. Their additional gravitational drag is best counteracted by putting them on a very light bike, to achieve a UCI-legal 6.8kg.

I don't honestly believe this, but may deploy this obscure justification if I eventually buy some Cosmics.

blorg

If they are what you have and they are clinchers then by all means use them; if however you had the choice of the Cosmics or a lightweight clincher I would go for the latter. I just don't think they are going to make you go any faster/make it any easier, that's all.

I emphasize clincher just from the point of view it's a long way around, you don't have a support car and so could be stuck if you got a puncture.

Bear in mind that half the pros don't bother to use deep sections on mountain stages, and the Marmotte is certainly a mountain stage. I'm sure they could get the bike to 6.8kg for that matter even with the deep sections...



EDIT: Whoops, meant this (I don't think anyone would question that this guy can climb):

cdaly_

rottenhat wrote:

10mm is a fairly significant proportion of the length of a stem (and by extension, the lever you're using to steer the bike)

Don't forget the lever you're steering with is the length from your hand to the head tube, not just the length of the stem. My setup is about 255mm of a steering lever (460mm bars with 110mm stem) so shortening the stem by 10mm would change that to 250mm for a difference of 2%.


I think...

Junior

Simply put no for you some of those things won't make any difference, due to your performance level. However at the top end of the sport every little thing counts to getting the maximum advantage from the power a rider is putting out. Although in saying that, power isn't everything, it's the ability to use it that is.

For example Armstrong spent 250k (est) on that narrow bike the F-One and while the setup made him more aero and he gained time, the position compromised his power output, which towards the end of a TT meant he was losing the advantage that the aero gave him.

A rider at the top level with good core flexibility will be open to suggestion on position, setup, wheels etc because if they can make them go faster at the power they are at they will try it, and they will see an advantage. Think of it this way, if something makes a rider 2/10's faster per KM, imagine the gains that can be gotten over a 40km TT. Also at the power level they are at, imagine the hike in power thats needed to get faster ...

Raam

So should I buy the bloody carbones or not?

Ryaner

Raam wrote: »

So should I buy the bloody carbones or not?

The standard Cosmic Carbon SLs are only 1740g which isn't far off most of the climbing wheels I looked at recently. All were 1400-1550g. For Ireland too, there is mostly flat or rolling hills where aero makes the benefit.

At least that is what I'm telling myself with my decision to get the powertap version. There isn't much choice of pre-built power tap wheels.

Raam

Ryaner wrote: »

The standard Cosmic Carbon SLs are only 1740g which isn't far off most of the climbing wheels I looked at recently. All were 1400-1550g. For Ireland too, there is mostly flat or rolling hills where aero makes the benefit.

At least that is what I'm telling myself with my decision to get the powertap version. There isn't much choice of pre-built power tap wheels.

But you are talking about the Marmotte, where it will definitely make a difference. The less rotating mass, the better.

Ryaner

Raam wrote: »

But you are talking about the Marmotte, where it will definitely make a difference. The less rotating mass, the better.

Indeed, however as crazy as I am, I'm not building the bike solely for the Marmotte. I intend on using it setup identically in numerous other sportives over the next few years.
Most of the weight on the version I'm getting is in the hubs which is much less affected by rotational inertia.

Who knows, but I do think I'll have to test both sets in a hill climb whenever I the wheels arrive in the new year. Compare figures and whatnot.

blorg

I'm not sure to what extent there is a point getting deep section carbon for sportives.

I got a pair of Zipp 404s for racing simply as I got a good deal and even I am skeptical about how much of a difference they will make there. 1278g so actually lighter than my lightest climbing wheels @1,355g but tubs so will still very much be racing only.

If it is for the bling, by all means go ahead, we are all guilty of buying the strictly unnecessary for the bling around here.

Lumen

blorg wrote: »

I'm not sure to what extent there is a point getting deep section carbon for sportives

There is no objective justification for using them in amateur racing either.

I'm thinking Carbones for the (alleged) sound of them or Edge 45 clinchers for the weight weeniness.

blorg

Lumen wrote: »

There is no objective justification for using them in amateur racing either.

Well I've lost a race by a bike tyre width... that never happened in a sportive

Beasty

blorg wrote: »

Well I've lost a race by a bike tyre width...:)

Try pointing the wheel forward next time:)

Junior

David McCann rides 404's the whole time from what I've been told.

Zipp101

Raam wrote: »

So should I buy the bloody carbones or not?

Yes...because they are cool.They will also make you sound like your going faster.

Raam

Zipp101 wrote: »

Yes...because they are cool.They will also make you sound like your going faster.

That's good enough for me.