When I bought my Hope wheelset they were not only lighter, they roll better and have lasted forever. Good wheels are an investment worth paying for. Some people have mentioned saving overall weight. My endura singletrack shorts weigh 500g. Can't say I ride any quicker without them just thought id mention it.
You know when you wish you hadn't started something?
Yeah that 😳 😕
😆
Hope/Stan's wheels made me faster. Prove otherwise.
My endura singletrack shorts weigh 500g. Can't say I ride any quicker without them just thought id mention it.
Sadly for me it's the kilo and a bit cradled at the front of my shorts that slows me down.............. 😛
A few people get out the wrong side of the bed this morning?
Everyone can see you started the childish insults Al, likely because you are unable to explain your thinking. Looking at the other thread its obvious that you really don't know what to believe 🙄
The way I see it in lamens terms is the bike will accelerate faster, ie be snappier off the mark and handle better due to the lower lower weight, but it's not going to add any significant speed, especially with the nature of off road riding
Dug, if you can't understand my point, or that I've read the evidence and changed my position (I can accept you're incapable of the former at least), should I care? Cos I don't.
To paraphrase a legend: I'm right, and you know I am, best leave it.
Blimey! Having just fitted hope hoops / crest / nobby nics and saved 760g over the existing wheel/tyre set up I would suggest that I can definitely feel a difference in the way the bike rides. As to whether that translates to 'faster'; I'm not one for higher level maths, but given that the only power available is human, any small improvements to the mechanical elements must help. Acceleration has been mentioned, but gyroscopic effect will also be diminished by moving to a lighter wheelset. Just try holding your old (heavy) front wheel at arms length with it spinning, and tilt it from the vertical toward the horizontal. Then compare it with your new (lighter set). Then consider how many times you initiate that tilting action on the trail. Over a decent distance, I think that the slightly lower fatigue-inducing effects of both accelerating, decelerating and compensating for gyroscopic effect probably leaves the rider with lighter wheels (bike) in a better physical state, therefore able to go faster further with his (her) given limited resources. (throws two cents on the bandwagon before it rolls over him..)
Start thinking about the change in weight from the perspective of total weight; bike+rider+kit...
..you have to accelerate all of it, so a reduction of 760 grammes from ?100 kgs...
Ignoring the discussion if the effect of saving rotating weight makes a significant difference or not...
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...and even the article referred to by crikey mentioned that rotational weight becomes more significant under acceleration. Off-roaders tend to accelerate quite a bit compared to roadies, right?! So what might not be significant in some circumstances might be (more) significant for the OP's endurance race. While at the same time the wiki article stated that the measurable difference is not huge and can hardly be felt. 😐
So - really - make of it what you want or what you do indeed [i]feel[/i]!
.......................................................................................................................................................................................
...so ignoring that discussion for a moment - what I really don't get are these repeated remarks on 'rather loosing body weight and getting fit than spending money on parts'. Yes?! So what? Is this some sort of advisory board for naughty bikers? Bike watchers? Wouldn't we and shouldn't we all lose a few pounds? But was it the question? No, it wasn't!
You could also always argue that one should just race for fun, enjoy the camaraderie and not worry about weight advantages at all...
...but that wasn't the actual question! 🙂
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Back to the actual topic: I can feel it! I am a believer! And I am so so happy with my light-ish wheels (and tyres and tubes) as a result of this. It makes me fly! 😛
That's the whole point though - it is only 760g but given the frequency of the accelerations etc, any saving is going to make some positive difference over the course of an endurance race - which I believe was where all this came in? 🙂
Ultimately what's more fun, buying spangly new bike bits or going on a diet?
Exactly!
Crikey (and all other "disbelievers" for that matter),
1.
which scenario would you personally prefer:
a) (crikey minus 1 kilo) plus crikey's bike
b) crikey plus (crikey's bike minus 1 kilo)
c) "bah, it doesn't make a significant difference anyway, I don't want any weight saving at all"
2.
Should you prefer a) I'd be curious to understand why.
Should you also prefer scenario b) where would you want the weight to be saved?
If you go for c) you'll probably state that it's a function of weight loss divided by money loss times training time in relation to grmpfmpfblah...
Personally - and given the financial resources at the time - I would always go for b) (hock plus (hock's bike minus 1 kilo)) because it [i]feels[/i] like a huge difference when my bike is suddenly almost 10% lighter while it doesn't [i]feel[/i] like a huge difference when I am 1.2% lighter.
I mean, am I the only one who sees a difference in the unit that is being moved around (the bike) and the unit that moves around (me). A light bike just [i]feels[/i] great!
And I'd still argue the same principle is true for the rotational mass: there are units that just need to be moved along (e.g. the frame) and there are units which have to be spun up AND moved along.
We could also open a thread on unsuspended vs. suspended weight by the way... 🙂
Read [url= http://www.pinkbike.com/news/Santa-Cruz-and-Enve-Carbon-Interbike-2011.html ]this[/url] article, nothing scientific.
And this about them switching to carbon rims
Roskopp cites multiple benefits of the carbon hoops for the team, including carbon fibre’s memory – its ability to bounce back from a bend rather than deform – the material's help in resisting flats, wheel stiffness and lower rotating weight.
Now ask yourself why they are trying to reduce weight on a downhill bike.
Si - go & see Darren & Jonathan @ Strada. FRM/BOR rims are in.
Let's leave my suspenders out of it eh..? 😯
I put lighter wheels on a bike some time ago and I 'FELT' a huge difference.....
So I don't care as to the actual proved difference, (which I don't think is quantifiable in feel terms anyway) I was very pleased with the result. 🙂
After all look at all the different bikes and components available, it isn't possible to use formulae to see how each rides !
We could also open a thread on unsuspended vs. suspended weight by the way...
There is no need, I have already provided a link with a formula showing that a pound on the wheels equals two pound on the frame.
Edit: quick question
Two riders, same terrain, wind speed, identical fitness, body mass, muscle mass etc
One has a bike that weighs 30lbs
The other has a bike weighing 25lbs
Who will be quicker over 10 miles?
Hi skywalker,
my "suspended/unsuspended" was more about handling than efficiency. That's why I suggested a new thread. While dreading another outrage. 😕
Regarding your quick question:
I don't think that - at least initially - the "insignificant" brigade doubted the effect of weight savings as such. The main point was whether it's significantly beneficial to save a given weight at the wheels or e.g. the frame, wasn't it?
So high-jacking your quick question - if I may - it could come down to:
Two MTB riders, same terrain, i.e. quite technical XC course with up/down and technical passages, identical fitness, body mass, muscle mass etc
Both bikes weigh 25lbs and have the same spec, apart from
- Bike A has a 1.5kg frame (though same stiffness etc.) and 2.0kg wheel set
- Bike B has a 2.0kg frame and a 1.5kg wheel set (again same stiffness etc.)
Who will be quicker over 10 miles?
What are the 10 miles and how are they ridden? Of course the lighter bike will be faster, what is under disagreement is by how much.
Read this article, nothing scientific.
And this about them switching to carbon rims
If it's not scientific it's not worth reading.
Can anyone explain the science of fun to me?
I'd hope we're all capable of admitting when we get it wrong...
Congratulations - it's just that it's rare enough on STW for it to be remarkable - especially for somebody who gets so passionate about the viewpoint they hold as you.
For all those asking "which is faster" - well clearly all other things being equal, the lighter bike is, we're just arguing about how significant that is in a world where everything isn't equal. I should point out that I have a lighter full-sus than all but a handful on here, but the most significant advantages to that are when I'm carrying not riding (which in a former life I used to do quite a bit of in races).
No idea about the science but I noticed a significant difference loosing about 500g from one wheelset to another.
I'll liken it to the feeling when you've ridden a muddy trail and some mud builds on the side of the tyre (the stuff on the tread has flung off so nothing that would impact on rolling resistance). You hit some hard pack and feel that extra rotating mass in terms of slower steering and acceleration and it feels harder work especially up hill.
Erm, guys, this is about 500g on bike wheels. Aren't we over reacting?
You new here?
You're not like this on the other channel [img] 
[/img].
Lizzy just saw this and was like "what on earth are they arguing about, has someone had a fight?".
I can be like this there if you like ❓
Is Lizzie new to the internet?
Well I can feel a difference between heavy and light tyres, tell me clever STW folk that know all.....is it in my head?
no one is saying that, try reading the thread.
Rotating mass in bicycle wheels has an insignificant effect, however often the myth is repeated.
If anyone can show it makes a difference, rather than claiming it does, I'm open to having my opinion changed.
cynic-al - Member
TBF crikey me sober chum, so does non-rotating weight.
To me that says you were.
I'll tell you what, saving 500g on wheels is boring. You lot need to get out more.
skywalker, I know it's yours (and others') failure to get my point that's kept this thread alive, here's a chance to read some of the thread you seem to have missed, so you can let it go now?
cynic-al - MemberMy points are 1. losing weight doesn't make you significantly faster than the proportion of weight loss to overall weight on the climbs only...2. weight loss to wheels may make a little more difference, but not the 3x referred to in 1 touted in magazine articles...despite 3. your bike "feeling way faster" etc.
In other words, a mass on the tire has twice the kinetic energy of a non-rotating mass on the bike. There is a kernel of truth in the old saying that "A pound off the wheels = 2 pounds off the frame."
Keep reading that til you understand it.
OP.. my 2p. Lighter wheels are a proven car-park bike-test winning tactic. They are noticed as soon as you try to accelerate. But much of the 'lighter is better' physics is more applicable to a track or road bike, MTBs are very different and although the physics doesn't change, there are other factors that reduce the importance of lighter wheels on MTBs. ie the rougher the course, the less light + thin rims make sense.
For the last year or so I've been riding XC on the heaviest wheels I've ever used and I'm riding faster than I have done for a long time. (training effect? maybe but not really!) I found this suprising, but there's some points that explain it -
Light wheels accelerate to a set speed in a set time with less power input. But once at that speed they have less intertia and are decelerated over bumps more easily.
So you spin em up to speed and think 'wow, fast bike' but you need to keep putting that effort in to maintain speed. A heavier wheel feels slower initially, but once rolling it should maintain speed more easily. One may well balance out the other. A bit like frame flex or the 26" vs 29" debates, it all comes down to the fact there's no such thing as free energy, energy put in is just dissipated in different ways and we just want to use it effectively.
The other factor is that a heavier wheel is often due to a wider rim, and in my case also a UST tyre. Low pressure tyres on wide rims mean lower rolling resistance off-road, as well as grip and float that help maximise the momentum of the heavier wheel.
Combine this low rolling resistance and high momentum of these wheels and I can understand why they 'feel fast' despite being heavy. Your muscles quickly gain or lose strength based on the regular efforts you put in, so you get used to accelerating heavier wheels pretty quickly anyway.
Lighter wheels are good if all other elements are equal, but it's not the most important factor. It's the most easily measured and 'sold as a benefit' factor though.
In your case for endurance events I'd go for something light, while being happy to trade 50-80g a rim for a wider section and the ability use a lower pressure tubeless tyre. Comfort and efficiency count for more the longer you ride. Pacenti's new TL28 rims (28mm width) are very light for the size and are tubeless ready.
skywalker - Member
Keep reading that til you understand it.
I understood it the first time I read it, shame you couldn't even link to it 🙄
Why not use our brains? What you (and the article) ignore is, as ever, the relevant detail.
1. the effect of conservation of energy which means that the heavier wheel gives more energy back and takes longer to slow down when the bike decelerates (like the F1 KE system) and 2. that formula accounts for pure acceleration only - one does not spend an mtb race constantly accelerating.
You and I don't know the extent of these effects...when I ride/race I am able to keep what I consider a fairly constant speed...and it's established that at a constant speed weight at the rim has the same effect as non rotating weight.
Until someone's attached an accurate acceleromter (sp) to a bike we'll never know who's right.
Here's my take on things, based on races I used to do...80kg + 10kg bike, losing 500gm of (non rotating!*) weight = 0.55%, say I spend 70% of my race climbing, my time will be 0.385% quicker, which over 90m equates to 0.347% = 20 seconds
* We don't have the info to do rotating, but even on your wiki formula, which is way too high as it ignores significant factors, that's 40 seconds.
When I was racing (masters, the tightest category in Scotland) it would be pretty much unheard of for 2 places to be separated by 20-40 seconds, and it would be interesting to see what times separate riders in 12 hour events.
Finally I would say it's pretty rare for anyone who's serious about racing, and therefore finishing in the higher and more tightly packed positions, to be able to save 500gm off their wheels or bike affordably!
Keep reading that til you understand it.
Aw bless, gone quiet, probably bed-time.
You still going on 🙄
Ha ha, bored now you don't understand?
I got bored of you ages ago mate.
Making up your own theories based on nothing, nice.....
Even better!
You'd have some credibility if you even tried to debunk what I've said, but you can't.
Best thread outcome for a while! 😀
Can't and can't be bothered are slightly different.
Talking to you is like trying to teach a child that doesn't want to learn, pointless.
Ha ha it gets better
[img] 
[/img]
Skywalker, you've proposed that you are a physics wizz, but seem incapable of dealing with any of the questions asked.
Give your mum a kiss and get off to bed now, there's a good lad.
*high fives*
If you read that link from beginning to end you wouldn't be asking such stupid questions and you would realise that you don't actually have a valid argument. You are just making yourselves look stupid by thinking you know what you are on about.
It deals with everything you need to know.
Edit: Plus there is the analytic cycling site if you are still having trouble figuring it out.
I'll tell you once more, then off to bed you young scamp.
Small changes in wheel weight and rotating weight are insignificant in bicycle performance. When you accelerate your wheels you also have to accelerate your bike, your camelback, your helmet and most importantly, you.
This is easy to demonstrate; if you don't accelerate all these things, you will leave them behind.
Go and look at the article you quoted, and see what it says about lightweight wheels, then apply this to the real world.
And don't forget to brush your teeth.
