I built myself a set for about £210 with some very stingy buying (Those Ambrosio tubeless rims that were posted on here, a set of Pacenti (bitex) hubs, and Dlight spokes which I slightly regret (I chickened out of my usual Lasers but now I wish I'd gone with those), they turned out at 1570g. Can't complain about that, even if they are a total bollocks to put tubeless tyres on.
Worth it? Well, for me, yes, because they feel good. That rocket-powered first couple of stabs of the pedals still feels fantastic, even if it makes no real difference in speed or times. But if it feels good to power away, then I'll do it more and probably end up going a little faster over a route. And there's been no downside- they're not delicate, and they have 30c tyres on so it all rolls rather lovely.
One thing I did realise, belatedly, is that if you get just the right moment in the fiasco that is road disc standards, you can just use old 29er wheels that nobody wants any more. So I could have just used my old WTB Strikers that were on my hybrid, that weigh 1550g and cost me £90 a few years back. Skinny rims, QR, tubeless, perfect for my road bike but never mind.
The light feeling of the wheels will be primarily in the rim and tyre, with a bit in the spokes and none in the hub (saving weight in hub will feel no different than saving weight on seat post)
So how much lighter are the rims in the 1570g wheel compared to the rims you used before?
I have found (outside of tubular rims) that rims are typically around 400 - 450 so we are really just talking about 50 grams per wheel which could make a difference to feel but surely not that much?
Last week I changed from 600g tyres to 400 gram tyres. Have to be honest that I hardly noticed the difference in feel of the bike.
I wonder if the feel of the light rims noticed most when moving the bars honking out of the saddle - the steering is so much lighter. Never notice it in the saddle.
I have found (outside of tubular rims) that rims are typically around 400 – 450
Yeah, not that much difference between 25 and much larger on LB's site. But adding width seems to incur a reasonable penalty.
I'm still on my 350gm alphas. Rim brakes too!
35mm is where aero benefits begin and 50mm is crosswind troubles begin. 45mm is a good blend.
kerley
Free MemberThe light feeling of the wheels will be primarily in the rim and tyre, with a bit in the spokes and none in the hub (saving weight in hub will feel no different than saving weight on seat post)
So how much lighter are the rims in the 1570g wheel compared to the rims you used before?
Nah, it's pretty well spread right through the wheelset in this case- ironically the saving in the rim is proportionally the smallest part as they were already not terrible, and it's the same tyres. OE hubs can be absolute bricks). And no, it's not the same to save weight in hub and seatpost, it's still mostly rotating mass, just not as pronounced as it's closer to the axis.
Sorry, but that’s bobbins. A spinning hub on its own has almost no rotational inertia, so a little more mass at the hub will make absolutely naff all difference to the feel of a wheelset on the bike until you pick it up.
Pick up a loose hub, put it on an tight axle and spin it. It wont spin for long. Do the same but with 100g of blue tac (spead around the spindle) on it. There will be almost no difference in both the energy needed to get it going or the duration it spins for. Now, build a wheel on that same hub and spin the wheel. Now add the same 100g bluetac to the rim in 4 equidistant locations and do it again to the same speed. Not only will you need more force to get it going, but it will spin for longer. Your 100g makes a significant difference at the rim, but practically none at the axis of rotation. You can test this by rolling a disc and a hoop of equal mass down a slope under gravity. The disc will win every time as so much of its mass is close to the axis of rotation and thus irrelevant to rotational inertia.
I have changed hubs alone on wheels and ridden them and the difference was obvious. Not as big as the same difference at the rims, of course, but then OE hubs can be very heavy.
I don't need to do random primary school experiments with blutac when I'm talking from real world experience but thanks.
Northwind
Full Member
I have changed hubs alone on wheels and ridden them and the difference was obvious. Not as big as the same difference at the rims, of course, but then OE hubs can be very heavy.I don’t need to do random primary school experiments with blutac when I’m talking from real world experience but thanks.
I'd say your "experience" was somewhat biased by either your expectation or maybe, possibly the bearings, whereas my "primary school experiments" are at least backed up by science and evidence...
I = MR^2. Do the math and work out the difference. Most of your hub mass difference is within a few mm of the rotational axis - say 10mm radius, so R^2 (in m) is 0.0001. Most of your rim mass is ~ 310mm from the rotational axis, so R^2 is 0.096. So whatever your change in hub weight, mass at the rim is worth ~1000* more. In other words, 200g of hub weight is worth 2g of rim weight.
You think you can feel that???
I’d say your “experience” was somewhat biased by either your expectation
I would replace "somewhat" with "definitely". If you can honestly feel the difference of a 100 gram lighter hub then I have a load of mattresses with a pea underneath the bottom one that I would like someone to find...
Can't believe this whole thread is going on and on about light v aero and no one has mentioned tyres
The thread is about wheels, I started another one about tyres 🙂
You lot keep slipping back into science and obsessing about proving stuff.
This is the subjective, lighter is betterer thread. If you want to start with yer fancy equations and empirical evidence (gah!), bugger off and start a thread for like minded boffins. 😁
Not getting into the debate about the science, but I bought some scribe 38-50 carbon rim brake wheels, I live in the hilly part of the south lakes and they 'feel' smoother than the two previous sets of aluminium rim wheels, but as mention above it can all be very subjective?
They do look nicer though!
People keep confusing the two, Miles!
Life is too short to ride heavy wheels. It's the biggest improvement you can make to many bikes outside of getting fitter yourself.
When you can get a set of 40-50mm aero weapons for ~1550 grams and £800 that's the best of both worlds. Speed on the flat, spin up easy etc.
If you don't believe it then buy a second hand set and if you don't feel a difference v a stock alu low profile rim then sell them on. You won't have lost much!
When you can get a set of 40-50mm aero weapons for ~1550 grams and £800 that’s the best of both worlds. Speed on the flat, spin up easy etc.
1550g doesn't tell the whole story as I showed above. Hunt Wheels for example have low weights, but the rim weights are often comparatively high when compared to others and Hunt save mass on the overall wheelset by using a low spoke count and lightweight hub, both of which matter far less to the feel of the wheelset.
For example, A Hunt Limitless 48 rim is only 22.5mm wide internally, but 35mm wide externally and weighs 510g A Light Bicycle Falcon Pro 45mm deep rim with a 24.5mm internal width and 31mm external width is ~400g. As such, my wheelset, with comparatively heavy hubs and more spokes is actually slightly lighter.
It's a similar story with the Carbon 50s, but maybe the Aerodynamacist rims are better - there's no rim option, so I can't tell.
Yes but I'm not comparing similar 50mm wheelsets, I'm comparing v the generally heavy (1.8-2kg), a bit rubbish stock wheels that most normal road bikes come with.
The hunts or your super researched wheels will still feel better/faster/easier than the stock rims which most people upgrade from. Arguably when climbing steep stuff at low speeds the Hunts would be better than your wheels as they are still lighter overall. Let's be honest though is it really that likely to be noticeable?
Yes there is loads of marketing spin, but it's not really any different to any other product category!
Arguably when climbing steep stuff at low speeds the Hunts would be better than your wheels as they are still lighter overall. Let’s be honest though is it really that likely to be noticeable?
No, the Hunts are still heavier, but only by a tiny fraction, maybe 3-4%, but what I'm saying is that more of my...lightness? is in the rim, where it matters, hence even though on paper mine are only a fraction lighter, becase of where the mass is, they should feel significantly better, like shaving 200-250g (1/2lb) from your rims/tyres.
I suppose what I'm saying is, don't just buy on wheelset weight, try and find out where that weight is in the wheelset. Hunt's carbon spokes will help a little here as they're 25% lighter, but even that is only 20-24g per wheel.
Is there a better place to go than LB for rims?
Nextie often have more variety, but are sometimes slightly heavier, but only 5%.
I’ve got both - have a look at the “things I’ve built thread” for a selection of Nextie and Light Bicycle rim wheel builds along with their weights.
Daffy
Full MemberI’d say your “experience” was somewhat biased by either your expectation or maybe, possibly the bearings, whereas my “primary school experiments” are at least backed up by science and evidence…
You're making the exact same mistake you already made, again. My expectation was that I wouldn't feel any difference, in fact for a long time I felt exactly as you do- I was surprised that there was an improvement and it took a little while to admit I'd been wrong.
And it was replacing a free-rolling cup-and-cone hub with a brand new cartridge bearing hub so the only difference the bearings would have made, is more friction (though, on an inconsequentially small level of course and not worth mentioning)
But you carry on.
Science doesn’t lie and the math isn’t wrong, but by all means keep telling yourself that it does and is.
Either there’s another variable that you’re not mentioning, or it’s bollocks.
Daffy is right, the science doesn't lie. That why it exists, why we don't measure things by feel etc.
I hate the 'science doesn't lie' line. Science is just a body of evidence. The problems happen when people take that and extrapolate, which we always do. It's the extrapolation that's the tricky part.
Another thing. Whilst it does happen that people spend money on something and want to believe it's better so they perceive improvements that aren't there - it's not guaranteed. Some people are honest enough and perceptive enough to make rational judgements.
My money is on the modelling not accurately replicating what actually happens on the road.
Math? WTAF is math? Unless you're a septic, hang yer head in shame... 😕
You lot still arguing about science and evidence? Tsssk. Warrawasteoftimeandeffort... 😁
Molgrips the "science doesn't lie" line is completely appropriate when someone is claiming to have felt a difference that just can't be there.
I thought we had done the whole "your body doesn't measure things well" thing to death, surely?
Do you measure distance by looking and guessing? If your ride feels like harder work does that mean is was slower or do you look at power, speed etc?
We can obviously feel things, even minor changes. If I change a part on my bike and make it 200 grams heavier or 200 grams lighter I can feel the difference when picking up the bike. I wouldn't be able to tell you it is 200 grams different but I would know it was lighter or heavier by a small amount.
My point on this particular example is that while you may feel that the bike is a tiny bit lighter there is no way you could feel whether the hub shell had been reduced by 100 grams, or the axle had been reduced by 100 grams or indeed the steerer tube had been reduce by 100 grams. That is where I would call BS.
A person may feel that 200gm, they may not. But they may think they feel a difference that isn't there. You just can't trust it.
Agreed on your specific example.
Molgrips the “science doesn’t lie” line is completely appropriate when someone is claiming to have felt a difference that just can’t be there.
What difference exactly are we talking about again? The lighter wheels or the hub thing?
I might struggle to explain Northwind's observations on hubs but I'm not going to say that it can't be there. Anyone with a knowledge of science and its history should feel pretty nervous about saying things like that!
I'd put that anecdote on the pile with the other anecdotes and treat it accordingly. That is not to say it's worthless, it's just heavily caveated. Anecdotal evidence is still evidence, of a sort, just don't treat it as if it were higher grade than it is.
WTAF are you talking about @Molgrips ?
This isn’t quantum physics, is ****ing classical mechanics. There is literally no more proven vein of science/math.
Mass at a distance exerts or resists a greater force equal to the square of that distance.
This is Key Stage 2 Science. My 8 year old can do this stuff.
A person may feel that 200gm, they may not. But they may think they feel a difference that isn’t there. You just can’t trust it.
I agree to an extent in that I wouldn't trust someone to feel a 100 gram difference in an 8kg object but there comes a point where you can trust feel.
If you give me a 50 gram object and a 10kg object I will be able to feel which is heavier 100% of the time and I would be happy to put everything I own on getting it right!
This isn’t quantum physics, is **** classical mechanics. There is literally no more proven vein of science/math.
Not that part you prune.
The question is whether or not it makes a palpable difference.
Mass at a distance exerts or resists a greater force equal to the square of that distance.
This is Key Stage 2 Science. My 8 year old can do this stuff.
You apparently can't though, you appear to be confusing it with the theory of gravity 😉 And I'm pretty sure it's not KS2 either.
No - I'm not. Classical Mechanics studies objects in motion, this includes the branch of Analytical Dynamics which specifically covers inertia - the very thing we're talking about. I thought you had a degree in Physics...?
I = MR^2
If R is small, I is VERY small unless M is bloody huge. Where R is equal to or greater than the magnitude of M, M can be small and still give a large value for I. Thus rim weight on a bike is literally worth 1000X more than hub weight unless the hub has some monstrous diameter like a Rohloff or a hub motor.
Whilst I don't doubt that NW et al can feel the 1/2lb difference that bike weight (regardless of where its is on the bike), what I do doubt is that you can really feel it when you step on the pedals and accelerate, especially if the bike is not at rest.
Sorry, I'm not gonna listen to a bloke that can't spell 'maths' - twice 😝
