- This topic has 50 replies, 34 voices, and was last updated 6 years ago by JackHammer.
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When does weight really matter?
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mjsmkeFull Member
Coming from an XC background I’ve always read and been told lighter is better. Now I know it’s not the case unless racing all the time.
So I did a bit of an experiment. My hard tail has DT Swiss M502 rims (30mm internal) on 350 hubs at 1905g and my full sus has Sram Roam 40’s (21mm internal) but at 1608g. Last weekend i seapped the wheels over putting the lighter, narrower wheels on the hard tail for a muddy ride. They also had lighter tires so saved a good 500g in total. I didn’t really notice the bike feeling lighter except for picking it up and on a few fast road sections. I’ve not yet ridden the full sus with the heavier wheelset but just wondering if it’s really worth the weight penalty for a wider rim?
Fresh Goods Friday 696: The Middling Edition
Latest Singletrack VideosFresh Goods Friday 696: The Middlin...tjagainFull MemberIs your new hip ti or stainless tho Ton? should have gone for the TI option!
tonFull MemberIs your new hip ti or stainless tho Ton? should have gone for the TI option!
good old british stainless teej, or so i hope…….. 😆
legendFree Memberton – Member
every man can lose a stone in bodyweight, for free*targets 9st for 2017*
tonFull Memberwhich of my limbs do you advise me removing
just cut your hair……..hippy
aazladFree MemberBased on using single ply and dual ply tyres on the same bike, I find the extra half pound per wheel results In better momentum (helping the bike carry speed and roll over rough stuff) which for me outweighs the weight save. Surely if you’re climbing at a steady speed the rotating weight of the wheel doesn’t really matter. I can understand the slight reduction in acceleration and deceleration performance but the benefit of momentum must also play into it. It’s a balance.
fifeandyFree Member@ton, i can try losing a stone, but are you sure 8st is a healthy option for a 5’9 guy?
tonFull Memberbut are you sure 8st is a healthy option for a 5’9 guy?
i reckon it is about as healthy as 9 stone is. 😀
chilled76Free MemberWhen it’s the sum of parts. I can feel when I’ve lost or gained about 2kg of body weight.
So 1-2kg on a bike is significant on a climb.
People often say “it’s only 300g difference”. Do that across 6 components and you’re nearly at 2kg.
Little weight differences add up, so if you want a light bike you need to look at every component.
kerleyFree MemberI’ve always read and been told lighter is better. Now I know it’s not the case unless racing all the time.
Not sure how you have come to that conclusion. Lighter is better for me as I prefer riding light bikes. I don’t race and my riding is solely for pleasure. Additional pleasure comes from riding a lighter bike.
It is that simple.
firestarterFree MemberWhere as I find additional pleasure in the additional comfort fat heavy tyres and wide wheels bring. I do ride rigid though
JAGFull MemberPurely from a physics point of view then Mass affects acceleration.
Force = Mass x Acceleration
Less mass means less Force (energy or power) is required to accelerate at the same rate or that you can accelerate at a greater rate with the same Force (energy or power). So weight is ALWAYS involved.
On a bike it can be difficult to detect the change simply because there are so many other factors that obscure this effect.
As covered in some of the posts already.
andreasrhoenFree Member@aazlad-bloke:
I find the extra half pound per wheel results In better momentum (helping the bike carry speed and roll over rough stuff) which for me outweighs the weight save.
interesting point! Never thought this way around.
You say: on certain trails a “high momentum” wheel will be faster.
Might be.@JAG-bloke:
Purely from a physics point of view then Mass affects acceleration.
Force = Mass x Acceleration
This is correct.
But what aazlad-bloke says is also correct:A “moving mass” has energy stored. Moving at the “same speed” the higher mass has more energy stored.
This – indeed – might help to
carry speed and roll over rough stuff
But also clear: aazlad-bloke has to put more energy into his bike.
If the trail is downhill: gravity helps.
Uphill: he needs to be stronger and always has to keep a “minimum speed” to gain from his “high momentum” wheels…
aazlad-bloke uses his wheels to store energy.Mmhhh
Possible.
Might be the case for certain trail profiles and very strong bikers.medlowFree MemberSoon after I bought my CX bike I changed the below:
Dropped 650g when changing the wheels
Dropped 300g when changing tyres too.
Dropped 300g by changing the cassette also.= 1150g, 1.15kg weight saving.
The difference was night and day. Acceleration, running with it on my shoulder and overall agility of the bike was much improved.
I’m only 8.5stone and the bike weighs 8kg, so dropping 1.15kg was very noticeable.Although, on the flat you might actually feel a benefit of heaver wheels as they roll for longer. Keep the momentum better. But give negative results on the hills or sprint accelerations.
Bike weight advantages are so subjective. 10 different riders will have 10 different views. Mathematically it must make a difference but the benefit of the difference has different affects on riders views.
A guy who is a lean racing whippet might have the fitness to not care about saving 500g.
Another guy with the same fitness level might not want anything to hamper his progress, so 500g is critical to him.
Another guy might be 19stone, so 500g may not make any noticeable difference to overall.
Another guy does not have the extortionate amount of pennies required to go hunting grams, so ignores weight figures.
Another guy just wants strength and dependability so does not give a sh1t about weight.Build the bike that feels better for you.
You have to experiment yourself and decide yourself, on your own circumstances and what you are looking for from your steed or riding experience..avdave2Full Memberevery man can lose a stone in bodyweight, for free
That would put me down at around 7 1/2!
BezFull MemberThat would put me down at around 7 1/2!
And you’d still have a stone to lose then, of course 🙂
mjsmkeFull MemberInteresting stuff! I thought my DT wheels were heavy but after looking around they’re lighter and wider than Hope tech enduro wheels.
After riding with 30mm rims with 2.3 tires (Maxxis DHF and Aggressor) there is a noticeable drop in grip when going back to 21mm rims with 2.25 Hans Dampf and NN which felt great until riding my other wheels/tires. Im only 60kg so never had a problem with burping tires or wheels braking.
2 things im tempted to try:
Wider tire on my narrower wheels keeping the weight down but might have an odd shape.
Lighter tires on wider rims. My current Maxxis tires arnt exactly light.
taxi25Free MemberMedlow says it all really.
For me itsLighter is better for me as I prefer riding light bikes. I don’t race and my riding is solely for pleasure. Additional pleasure comes from riding a lighter bike.
It is that simple.
amediasFree MemberAdditional pleasure comes from riding a lighter bike
Until you start hitting the point where the light weight parts aren’t up to the job or perform worse…
It’s never black and white, shades of
greybrown all over and endless compromises and balancing acts.kerleyFree MemberIt’s never black and white, shades of grey brown all over and endless compromises and balancing acts. [/quote}
I ride very simple bikes of very easy terrain and it is very black and white for me. I don’t find myself making compromises let alone endless compromises and balancing acts.
DaveyBoyWonderFree MemberLighter is better for me as I prefer riding light bikes. I don’t race and my riding is solely for pleasure. Additional pleasure comes from riding a lighter bike.
I’ve had some pretty light bikes in the past and enjoyed riding them at the time. The most enjoyable-to-ride bikes I’ve had were my last Orange Five which was built with 160mm forks and massive tyres which you could steam roller through stuff on and my current Alpine 160.
My riding is now solely for pleasure, given up on racing but for me, angles, tyres, the right amount of suspension and a dropper post = more enjoyment than something light. Of course I could chuck a load of money at making my Alpine lighter but I love riding it so I’ll chuck the money towards Greggs and beer.
tjagainFull Memberkerley – Member
Not sure how you have come to that conclusion. Lighter is better for me as I prefer riding light bikes. I don’t race and my riding is solely for pleasure. Additional pleasure comes from riding a lighter bike.
It is that simple.
I agree with this
Where as I find additional pleasure in the additional comfort fat heavy tyres and wide wheels bring. I do ride rigid though
the two are not mutually exclusive Tyres don’t need to be heavy to be fat do they – My bike has relatively wide tyres but still weighs comfortably under 25 lbs which for me is the benchmark of a light bike
amediasFree MemberI ride very simple bikes of very easy terrain and it is very black and white for me. I don’t find myself making compromises let alone endless compromises and balancing acts.
You do make compromises and you are already balancing your needs, even if you don’t realise it. You’ve found the optimum tool for your use case, but you could still go lighter again, I very much doubt you’re at the limit of lightness.
The point is, as you have already acknowledged, your current riding is served adequately by your current equipment, and if your riding is consistent then your needs don’t vary much.
If on the other hand your riding is extremely varied you have to make more compromises (or keep changing bikes mid ride!). One of your requirements is the feeling of a light bike, as it’s important to you, it’s also important to me, but not at the expense of other performance metrics.
If you moved or your riding changed you might have to compromise, either by changing your kit, or if the feel of your bike is more important to you, then by riding differently.
ie: I could use lighter wheels or tyres, but I’d end up walking home more often, so I compromise. Just because you’ve already reached your compromise doesn’t mean you haven’t made them, or balanced your needs already.
Weight may be important, for some it might be the most important factor, for others it might be further down the list, doesn’t make either of those people right or wrong, it just means they have different requirements.
mjsmkeFull MemberI cant help but want another pair of wheels now. Just cant find any that tick the boxes:
27.5
15×100 and 12×142
26-30mm internal width
1.7kg or less
XD freehubI’m only 60kg so don’t need to be super strong.
doggycamFree MemberMaybe try these ??
https://www.bikeradar.com/road/news/article/dynamic-wheel-weighting-51327/esselgruntfuttockFree MemberIf your’e really that worried about weight, have a crap, shave & a haircut before you go out on the bike.
tomhowardFull Member27.5
15×100 and 12×142
26-30mm internal width
1.7kg or less
XD freehubHope pro 4 on WTB KOM i29 light spokes…
kerleyFree MemberYou do make compromises and you are already balancing your needs, even if you don’t realise it. You’ve found the optimum tool for your use case, but you could still go lighter again, I very much doubt you’re at the limit of lightness.
I really don’t. All that stops my bike being lighter is the fact I don’t want to spend vast amounts of money on it (I do light on a small budget). I suppose that is a compromise but not the sort you are referring to.
keirFree MemberI tend to operate on the basis that if everything else is equal, lighter is better, but having had some weight weenie times, and broken parts to show for it, weight is no longer a primary selection factor for me.
i now tend to go for the lightest parts that are reasonably priced and up to the task. a lot of the time i don’t even look at the weights except on “big” stuff like frames, forks, wheels etc.
Strong. Light. Cheap. Choose two – as valid today as it’s ever been
ndthorntonFree MemberDefinitely lighter bikes win out on climbing, but I also think a heavier bike does help on the descents. Bike tends to hold its line better with reduced tendency to ping off stuff.
So maybe the answer is to ride a lightweight bike to the top of the hill and then fill a frame bag full with rocks for the decent.
That would have the additional effect of gradually reducing the height of my local hills and in the very long term eventually remove the problem altogether.
andreasrhoenFree Memberand then fill a frame bag full with rocks for the decent.
Excellent. This works. 😈
Funny:
Carbon sleds with Pinion gearbox.
These bikes are still 2 kg heavier than comparable plastic bikes.The manufacturer of the Pinion sleds claim that this isn’t a problem so…
Question then: are these bikes fun?
Do they win races?does weight really matter?
Maybe above questions might help to answer this question?
molgripsFree MemberDoes it matter according to what criteria?
Will it make you faster uphill? A bit.
Will it feel nicer to ride? Probably.
Will it fill the void? No.
I had an XC race bike which was 21.5lbs, with 1250g 26″ wheels. That accelerated incredibly quickly, and by heck it was noticeable.
mjsmkeFull MemberI’ll have to do a few experiments with my wheel and tire combos.
Just don’t know if I’ll really notice the benefits of going from a 21mm rim to 30mm on 2.25 and 2.3 tires. FYI most my riding is local woods, XC, and the odd trail center. FYI my wider wheels are nearly 250 grams heavier at 1908 grams.
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