Will I notice .5kG off Wheels and Lightening a Madone
As i cant afford to follow my dream and get a de rosa idol i'm wondering what i can do to lighten my Trek Madone and turn into more of a climber.
Its the 5.2 which has slightly heavier carbon and ultegra. Its also got some bontrager aero wheels weighing in at about 2kg, all up it weighs 8.5Kg with pedals, bottle cages and computer, so thats about 8Kg without.
I'm tempted by some Mon Chasserel wheels saving 500g. So the question is will i notice the difference on both short as well as longer climbs? I also do a few flat crit type races with lots of accelerations out of corners and a bunch sprint.
Upgrading to dura ace or lighter bars i cant see as cost effective, but are there any components that would see a decent weight reduction per £?
Its the 5.2 which has slightly heavier carbon and ultegra. Its also got some bontrager aero wheels weighing in at about 2kg, all up it weighs 8.5Kg with pedals, bottle cages and computer, so thats about 8Kg without.
I'm tempted by some Mon Chasserel wheels saving 500g. So the question is will i notice the difference on both short as well as longer climbs? I also do a few flat crit type races with lots of accelerations out of corners and a bunch sprint.
Upgrading to dura ace or lighter bars i cant see as cost effective, but are there any components that would see a decent weight reduction per £?
<hr><font>The trick is not MINDING that it hurts.</font>
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well, as i'm sure you already know buying lihgter wheels is one of the best ways of saving wieght on a bike due to certrifugal forces etc.
i'm not sure 500g of saving, even from wheels, will make a noticable difference though, i mean, that's like leaving one of your water bottles at home. try going out with just one bottle and see if you can tell the difference when compared with two. despite this, however, i still think it's the best idea and investment area. it goes without saying that you need to run the lightest tubes and tyres or tubs you can find to further enhance the effect.Only the meek get pinched. The bold survive.0 -
there is always the old favourite way of saving grams.... drop a few pounds of the old belly if you have it to lose!
much cheaper than a new set of wheels!========================================
http://itgoesfasterwhenitmatches.blogspot.com/0 -
henderson_mk wrote:there is always the old favourite way of saving grams.... drop a few pounds of the old belly if you have it to lose!
much cheaper than a new set of wheels!
aye.Only the meek get pinched. The bold survive.0 -
Pagem wrote:well, as i'm sure you already know buying lihgter wheels is one of the best ways of saving wieght on a bike due to certrifugal forces etc.0
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Pagem wrote:henderson_mk wrote:there is always the old favourite way of saving grams.... drop a few pounds of the old belly if you have it to lose!
much cheaper than a new set of wheels!
aye.
Aye indeed. Ive just come back from italy and was climbing really well but being beaten by someone 7kg lighter than me and an inch or so taller, his bike was a kilo lighter too. So ive been on a diet and lost 2kg+ already.
I'm asking about the wheels because ive promised myself that if i can knock off the full 7kg i can buy myself the de rosa. Thing is i cant keep that promise so itll probably be some lighter wheels instead.<hr><font>The trick is not MINDING that it hurts.</font>0 -
I wouldn't go for the mon chasseral personally but each to their own. I would consider the shamal ultras if you want a light set of clinchers (I have a set and am v. impressed). the above comment about aero is correct, though aero is usually costly. Easton make nice wheels that might be worth looking at.
In terms of components, you need to look at everything. Stems are a good place to save weight with cheap alu stems often being as light as carbon ones that cost 3 or 4 times as much. Do you have reasonably light tyres (e.g. PR2s) and light inner tubes? Seatposts are also a good place to save weight. 160g or so should be your target there.
sounds stupid but lightweight bottle cages are not a bad bet because they can be taken from one bike to the next. Planet x do some very light and not too expensive carbon cages.
Saddles ... each to their own. Toupe is a good combo of light weight and comfort for lots of people.
Pedals ... what are you riding right now? Look Keo Carbons are very good in the £ per gram saved quest.
Quick release skewers from Tune are also not a bad bet (sounds stupid again), but you could save about 70g for £60 odd and they can be taken to your next bike.
In terms of the groupset, depends on your plans for the next bike... possibly a DA chainset might be worth it?0 -
You can get an idea of how much difference saving weight makes on your climbing times by using this site. It doesn't actually matter whether you save weight off the wheels or off the rest of the bike or your body, because the energy required to overcome rotational forces is relatively very low. See this article at biketechreview for a full explanation.
Of course, it's (nearly) always good to shed the kilos off your body first, simply because it's cheaper!Jeff Jones
Product manager, Sports0 -
Depends where the weight loss of the wheel is - the further out, then yes, because of the moment of inertia which defines the amount of effort required to 'spin' a wheel - a lighter wheel will take energy to get it up to speed and likewise will consume less energy to keep it there - a pair of 1500g wheels will feel considerably different to 2000g wheels - simplistically, they should require 25% less energy to spin, but because of wind resistance, tyre hysteresis and friction it is a lot less. Losing 'dynamic' mass as opposed to 'static' mass (e.g. a water bottle) also makes a significantly greater difference to energy consumption. Because lighter wheels are a bit more 'tuned' and less overbuilt, a lighter wheel also feels more resilient and smoother.Make mine an Italian, with Campagnolo on the side..0
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Monty Dog wrote:Depends where the weight loss of the wheel is - the further out, then yes, because of the moment of inertia which defines the amount of effort required to 'spin' a wheel - a lighter wheel will take energy to get it up to speed and likewise will consume less energy to keep it there - a pair of 1500g wheels will feel considerably different to 2000g wheels - simplistically, they should require 25% less energy to spin, but because of wind resistance, tyre hysteresis and friction it is a lot less. Losing 'dynamic' mass as opposed to 'static' mass (e.g. a water bottle) also makes a significantly greater difference to energy consumption. Because lighter wheels are a bit more 'tuned' and less overbuilt, a lighter wheel also feels more resilient and smoother.
There are some colourful arguments on this elsewhere in the forest ... heavier wheels do have more momentum (at a given speed) and therefore decelerate less quickly, in other words, a heavier wheel takes less energy to keep it at a given speed as it doesnt "want" to slow down as much as a lighter wheel does ...
That said, accelerations are a major source of fatigue ... and IME at least having light weight wheels with as little weight at the rim as possible is less tiring than having heavier wheels, and I suspect would feel less tiring even if the lighter bike had the difference in mass made up somewhere else.
let the debate commence!!!0 -
Just buy the De Rosa cos it's what you want. Once you've spent that sort of money you'll want to spend every waking minute riding it.
You get the bike of your dreams and you'll lose weight into the bargin.
If you're married and buy the De Rosa chances are the wife won't speak to you for weeks afterwards either (or she kicks you out meaning more time to ride)
You win on so many levels that the De Rosa looks like the only sensible option IMO0 -
Lots of hard figures being banded around in this thread, can anyone point me to a source where all this has been tested ?
The only wheel test I've seen was the one in last weeks comic, and all that showed is that there's not much difference between wheels in an indoor velodrome.0 -
Ste_S wrote:Lots of hard figures being banded around in this thread, can anyone point me to a source where all this has been tested ?
The only wheel test I've seen was the one in last weeks comic, and all that showed is that there's not much difference between wheels in an indoor velodrome.
Tour Magazine (German) have done loads of wheel tests. Search online and you should find some of their stuff, though you might need to sprechen zie deutsch.
We're fundamentally just talking about the laws of physics with the wheel inertia issue.
Did the Comic's results have a different baseline for tubs and clinchers? As I understood it that was based around watts required to hold a constant speed? I haven't read the article in full to be honest.0 -
"wildmoustache wrote:Did the Comic's results have a different baseline for tubs and clinchers? As I understood it that was based around watts required to hold a constant speed? I haven't read the article in full to be honest.
They did use different baselines for tubs and clinchers, and it was based around watts to hold a constant speed. They didn't print what those baselines were though, which meant you couldn't directly compare tubs vs clinchers. The results for the clinchers were all within the error margin of the SRM cranks.0 -
wildmoustache wrote:We're fundamentally just talking about the laws of physics with the wheel inertia issue.0
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Personally if it were me I would scrimp and save until i could afford that Idol, cos you won't get any Trek to go or feel like a De Rosa.0
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Its probably psychological but it does feel good to shave a pound or so off the weight. It certainly feels more responsive on the hills (or is that my imagination ?)
I would look at the cheaper heaviest bits first to lose weight.
Go for a lighter bottom bracket and a titanium cassette like the Pro lite (150gms 10 spd) and you could shave off 300 +gms there alone. then look at your pedals they are heavy items you should be able to lose another 100gms there maybe.
You could lose at least 400 gms if you switched to non STI levers but thats probably` a bridge too far' but many do just that for TT's and hill climbs.0 -
There are as many opinions about whether light wheels work as there are people. I have one myself, but there's no point in saying what it is as somebody will inevitably flame me anyway. I'm not convinced that *anyone* understands the physics of wheel weight versus aerodynamics versus slope angle when climbing - including the site alluded to above.
Just buy whatever you think looks good - at least then you'll be happy about something, and won't have to try to resort to a quasi-scientific justification for what you've done... :roll:0 -
I hear good things about the Shamals' and would suggest handbuilt wheels but have to agree with the above that whatever you do to your Madone it will never be the De Rosa. Might as well flog the family silver now as it's one less knife the wife can throw at you0
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Everyone has missed the real reason for weight loss at the rim to be advantagous. When a bike is travelling at say 20mph the hub is moving at that speed but the top of the rim is moving forward at 40mph and the bottom of the rim is stationary. It is accelerating the rim to the top speed that takes energy. Some of this is returned as it slows to the bottom but not all. An aero rim is no real advantage on a climb unless it is as light as a non aero one due to the low speeds. The ideal of course is a light and aero wheel but we can not all afford Lightweights.
The usual anti Trek snobbery creeping in. I can not speak for the De Rosa but the new Madone is a superb bike to ride and is very light. A 56cm 5.2 Performance with Ultgra SL and Bontrager Race Lite wheels is 16.5 lbs with pedals. This weighed 1/4 lb more than a 58cm Madone 5.9SL with Dura-ace and Campag Bora wheels. These weights are from actually weighing the bikes.0 -
wildmoustache wrote:That said, accelerations are a major source of fatigue ... and IME at least having light weight wheels with as little weight at the rim as possible is less tiring than having heavier wheels, and I suspect would feel less tiring even if the lighter bike had the difference in mass made up somewhere else.
This isn't borne out by the study/model I quoted above on biketechreview, which is based on solid physics. Mr Willett summarises:
1) Aero is most important
2) Wheel mass is 10 times less important than aero
3) Wheel inertia is 100 times less important
So yes, it will take slightly more energy to spin a heavier rimmed wheel than a heavier hubbed wheel of the same mass (unless I've forgotten all my high school physics). But this extra energy is negligible when you compare it with what it takes to move a cyclist along. Negligible meaning that you won't notice if the mass was taken off the rims or if it was taken off the forks or any other part of the bike.
Here's a simple test: lift the bike up and spin the front wheel with your finger. See how little energy it takes to accelerate it from zero? Compare that to when you're actually on the bike and have to accelerate to an equivalent speed in the same amount of time. You probably can't do it, even with all your muscles in your legs working because it's such a massive difference in power.
The ultimate solution for the OP? Get a pair of decent aero wheels that are light and handle well, if you're doing crits and road races on them. If you're just doing crits, then good handling can be quite important, depending on how technical it is. If you're just doing hilly races, then aero is more important than weight unless the hills are very steep and very long.Jeff Jones
Product manager, Sports0 -
Agreed to a point. When you are accellerating a bike all weight is important but when riding at steady speed the only part of the bike that is still accelerating is the rim. As I said not all the energy is returned as it slows at the bottom so it is a good idea to save as much weight here as possible. A few years ago many riders thought that a heavy disc wheel was best for TTs but not many think that now and get the lightest disc they can afford.
It does not take much energy to spin a wheel up by hand but you are not getting it very fast. Try getting the rim speed to 20mph which is what is required to ride at 10mph. It takes quite a push.
The ideal wheel is a light aero rim with low spoke count and good stiffness. These cost a lot and are often not good in cross winds. If you are racing then aero must be a consideration but if touring at 12 to 15 mph it does not make much difference.
The dynamics of a bike and rider are very complex and often perceived or imaginary gains are the best as the mind thinks you will go better so you do. Just get the wheels you like and feel good with.0 -
i think we basically agree. aero is most important but wheels are the best place to save weight and light weight is almost always a good think
the thing about road racing is that it involves lots of accelerations, and you don't "get back" what you've put in from decelerations. By that I mean, once you're dropped, your're dropped, even if your heavy rim is decelerating slowly. I have one part of aero tubs that weight 1300g and another pair of aero clinchers that weight nearly 1900g with lots of weight round the rim. there is no doubt that i can notice the difference, even though it is less than 1% of total bike plus rider mass. And right on the rivet it would be enough to get dropped.0 -
wildmoustache wrote:i think we basically agree. aero is most important but wheels are the best place to save weight and light weight is almost always a good think
the thing about road racing is that it involves lots of accelerations, and you don't "get back" what you've put in from decelerations. By that I mean, once you're dropped, your're dropped, even if your heavy rim is decelerating slowly. I have one part of aero tubs that weight 1300g and another pair of aero clinchers that weight nearly 1900g with lots of weight round the rim. there is no doubt that i can notice the difference, even though it is less than 1% of total bike plus rider mass. And right on the rivet it would be enough to get dropped.
Further to this, I reckon you'd find it near impossible to tell the difference between two sets of 1900g wheels - one with most of the mass near the hub and one with most of it near the rim. And in practice, you don't find wheels with super light rims and extra heavy hubs anyway, so it's a bit of a moot point.
Road racing does involve a lot of accelerations, but it's nearly all air drag and translational forces that you're battling, not inertial ones.Jeff Jones
Product manager, Sports0 -
John Tiffany wrote:Agreed to a point. When you are accellerating a bike all weight is important but when riding at steady speed the only part of the bike that is still accelerating is the rim. As I said not all the energy is returned as it slows at the bottom so it is a good idea to save as much weight here as possible. A few years ago many riders thought that a heavy disc wheel was best for TTs but not many think that now and get the lightest disc they can afford.It does not take much energy to spin a wheel up by hand but you are not getting it very fast. Try getting the rim speed to 20mph which is what is required to ride at 10mph. It takes quite a push.The ideal wheel is a light aero rim with low spoke count and good stiffness. These cost a lot and are often not good in cross winds. If you are racing then aero must be a consideration but if touring at 12 to 15 mph it does not make much difference.
Touring: ride whatever you you're comfortable with and is reliable, but I think the OP was asking for more than a set of touring wheels.The dynamics of a bike and rider are very complex and often perceived or imaginary gains are the best as the mind thinks you will go better so you do. Just get the wheels you like and feel good with.Jeff Jones
Product manager, Sports0 -
On my TCR I swapped the original Mavic CXP22's on Ultegra with OE Hutcison Reflex tyres for the Reynolds Alta-Race and 23c PR2's seen in the sig photo.
Total weight saved approx 450g + much better rim and spoke aerodynamics. Acceleration is much better/nimbler handling and top cruising speed seems nearly 2 mph higher. Switching back to the original wheels plus a pair of 25c Krylions feels like I'm riding through treacle in comparison, cruising speed down, acceleration slower...
Cost of wheels and tyres, just under £200, grin factor...priceless 8)0 -
John Tiffany wrote:Everyone has missed the real reason for weight loss at the rim to be advantagous. When a bike is travelling at say 20mph the hub is moving at that speed but the top of the rim is moving forward at 40mph and the bottom of the rim is stationary. It is accelerating the rim to the top speed that takes energy. Some of this is returned as it slows to the bottom but not all. An aero rim is no real advantage on a climb unless it is as light as a non aero one due to the low speeds. The ideal of course is a light and aero wheel but we can not all afford Lightweights.
Quick couple of calculations here - climbing at 10mph on a 1 in 12 gradient you're gaining height at 0.37m/s. Hence 100g extra weight requires 0.37W more power (power = force x velocity; force = mass x g). Now given a typical difference of 10W between aero and non-aero wheels at 30mph (difference between best and worst in recent CW test) and that aero power requirement is proportional to the cube of speed, at 10mph the difference in power requirement between them is 10 / 3^3 = 0.37W!!! Of course most people don't manage a 1 in 12 at 10mph, so on whatever gradient they do manage that the difference in power due to weight will be less than the figure calculated above, hence less than the difference aero wheels make. Meanwhile at only 12mph with similar climb rate the aero wheels gain you as much as dropping 200g in mass. The point here is that whilst aero might gain you very little at these speeds, so does dropping 100 or 200g in weight.
Now for an acceleration one for the crit riders: Lets assume you're accelerating from 20 to 30mph, or in metric which makes the working easier 8.88 to 13.33m/s. Now lets say you have wheels with a huge 200g extra on the rim where we'll count it double (which is a reasonable assumption to allow for both linear and angular KE), therefore the KE of these rims before = 1/2 * 8.88^2 * 0.4 = 15.8J and after = 1/2 * 13.33^2 * 0.4 = 35.6J. Now if you manage this acceleration in 5s which is really pretty quick, that's only ~4W more for the heavier rims (or ~2W more than for 200g on the frame) - not really a lot. Here's the kicker though - remember before that the non-aero wheels took 10W more at 30mph, well that means 3W more at 20mph (so you're only 1W up when accelerating them there) and in fact by the time you get to 23mph the difference in aero is already more than the benefit you get from the lighter rim in terms of the power required for acceleration.0 -
so in summary then.......
if I had a budget, say of £600 for a set of wheels - which should I buy from this list:
Mavic Ksyrium ES,
campag Shamal ultra
fulcrum zeros
HED Alps / stingers.0 -
I'd say save it and put it towards a better frame0
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Anything but the Ksyriums, which are neither light nor aero.0
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05pro wrote:Just buy the De Rosa cos it's what you want. Once you've spent that sort of money you'll want to spend every waking minute riding it.
You get the bike of your dreams and you'll lose weight into the bargin.
If you're married and buy the De Rosa chances are the wife won't speak to you for weeks afterwards either (or she kicks you out meaning more time to ride)
You win on so many levels that the De Rosa looks like the only sensible option IMO
Of all the above arguments, this one appeals to me the most. Physics aside, aesthetically the madone which is the 05 model with the fin on the seat tube, coupled with the aero wheels just doesnt look like a svelte climber and a change of wheels wouldnt resolve that. I suppose because i'm only 5'6 climbing's my thing i now want a bike that reflects that.
On a 7km climb of 10-12% I was roughly 200m behind a chap weighing 7kg lighter than me + 1kg lighter bike. So the question is how much weight would i have to lose to claw back that 200m? (And yes im already cutting the calories and have lost over 2kgs so far)<hr><font>The trick is not MINDING that it hurts.</font>0