lighter road wheels--how much difference on climbs?

JamesB
JamesB Posts: 1,184
edited April 2011 in Road buying advice
Hopefully in right section :)

Currently using Mavic Open Pros, nice wheels strong and easily sorted if spoke breaks. But how much difference, to an average sportive rider (ie finish about mid point on timings--NOT a racer) would a lighter more expensive set of wheels REALLY make? . Looking for differences on the longer climbs not really steep stuff --ie for trip later in year to Alps :)
Currently using good tyres and light inners (Michelin Pro 3 / Conti lights)

although maybe at 85 kg its best to lose weight less beer :(

ta.
«1

Comments

  • frame and wheels two most important parts on the bike...lighter wheels will make a HUGE difference...if u go for something off the peg look at something with an uber light rim as this will make the most difference if you look handbuilt...TUNE hubs on DT RR415 rims with CR Ray Spokes...£690, 1350 grams enough said...:)
  • JamesB
    JamesB Posts: 1,184
    Looking at specs on RR415 they`re just a bit lighter though than my Open Pros, and I`m at top of weight limit? So is a lot of that low weight saved in teh hubs?
  • Yea defo TUNE hubs are massively light and their machined out off XOOX aluminium (depending on the model) amazingly strong. If you was worried about weight you could go RR465 which is double eyeletted but i dont no of anyone that has had problems with the 415's
  • Bobbinogs
    Bobbinogs Posts: 4,841
    although maybe at 85 kg its best to lose weight

    Yepp, that's the answer. Nice wheels will probably save you about 500g a set (making a few assumptions on my part) whereas it does look like you could easily lose a few kg by regular hill training and diet...and then you will really fly up those hills.

    Bear in mind 500g is one water bottle filled up. On your next training run time yourself doing a loop with an extra bottle and then tip it out and time yourself again, I don't think you will find much of a difference.
  • Gone up a bit in price now but have a look...

    http://www.bikeradar.com/gear/category/ ... team-31470
  • dcj
    dcj Posts: 395
    edited April 2011
    i would tell you aero profile usually has more performance benefit than lighter weight on a rolling or flat event. on etaps etc you normally have as much time decending or riding on the flat as going up

    if you are not actually going full gas then the reduction in time using a lighter wheel than normal is small enough not to be the reason for owning a set.

    by all means have the dream super light wheels as they do feel much nicer to ride -everywhere actually, except when its wet, downhill and they are made of carbon.

    be realistic though: you are not going to be 5 minutes faster up a mountain even if your name is shergar.
  • Ron Stuart
    Ron Stuart Posts: 1,242
    James, I don't know your proportions but judging by your last comment I would be in the business of shedding weight off myself first for a few reasons.

    1) You will possibly save a much bigger weight saving from yourself that the difference in the wheels.

    2) The money you will save from not buying as much food and beer will go a long way to paying for your wheel upgrade.

    3) At 85kg you need to be carefull about which lightweight wheels you purchase as some maybe not robust enough.

    4) I would do two upgrades, first yourself then second reward your efforts on losing weight by purchasing some lighter wheels.

    Lighter wheels need not only to be less in weight they still need to be strong and stiff with good bearings.

    My advice is get your weight down then research some upgrade wheels, maybe see if you can try some out.

    Mind you Magnus Backstedt's best ride weight was 93-94kg but he is 6'-4" and big with it. :roll:

    Also what lifecyclist was suggesting was a weight saving of around 1LB, you weigh in at around 187LB, lightweight wheels that are strong, stiff and have good bearings start in price at about £500 to £600. Good Luck :wink:
  • u no u can pedal down hill for extra speed...
  • dcj
    dcj Posts: 395
    3) At 85kg you need to be carefull about which lightweight wheels you purchase as some maybe not robust enough.

    4) I would do two upgrades, first yourself then second reward your efforts on losing weight by purchasing some lighter wheels.
    sound, sound advice from that man :shock:
  • lol....
  • unixnerd
    unixnerd Posts: 2,864
    I went from 2kg wheels to 1.5kg Pro-Lite Braccianos, at just under 200 quid it's the best money I've spent on the bike. Big difference climbing (and lots of hills up here in the Cairngorms).
    http://www.strathspey.co.uk - Quality Binoculars at a Sensible Price.
    Specialized Roubaix SL3 Expert 2012, Cannondale CAAD5,
    Marin Mount Vision (1997), Edinburgh Country tourer, 3 cats!
  • JamesB
    JamesB Posts: 1,184
    at 6ft my 85 kg is probably now slightly heavier than I should be :( ; but although 4kg more than last year timing myself on local climbs very little difference of note ; maybe a few seconds more on a 5 min climb, nothing significant given I`m not racing

    jermas; interesting article, may persuade me to cut down on saddle pack size too---although i dislike stuffings lots of bits in jersey back pockets :(
  • Just to clarify, 500g saved on the wheels has a greater effect surely than the same weight saved elsewhere, due to the rotating nature of the wheels :?:

    IMHO, a lighter pair of wheels does make a big difference uphills, and if you can lose some weight, that will increase your performance even more.
    Summer - Dolan Tuono with Sram Force and Dura-Ace 7850 CL Carbon wheels
    Winter - old faithful Ribble winter bike
    SugarSync cloud storage referral link (better than DropBox atm imho) https://www.sugarsync.com/referral?rf=mzo2tcrhm5gn
  • +1 peter101cycle
  • +1 peter101cycle

    Yep I think so lifecyclist2010, just thinking of a centrifuge in a lab........
    Summer - Dolan Tuono with Sram Force and Dura-Ace 7850 CL Carbon wheels
    Winter - old faithful Ribble winter bike
    SugarSync cloud storage referral link (better than DropBox atm imho) https://www.sugarsync.com/referral?rf=mzo2tcrhm5gn
  • Defo...its rotation mass...by cutting down a bottle it just saves weight, might as well go to the toilet properly before your ride, but because its rotation mass it makes much more of a difference.

    This is my main problem with off the peg bikes, manufacture feel they HAVE to put say ultegra group on where as they should put 105 and put the extra £300-400 into a better set of wheels, the bike would ride sooooooooooo much better.
  • mroli
    mroli Posts: 3,622
    Lightness isn't the only factor - going up hill you are putting a lot of force through the wheel, therefore strength is an important factor too.
  • Grifteruk
    Grifteruk Posts: 244
    Ive been lurking in this thread with interest to see peoples views and how it will change what wheels I run.

    I have just bought a set of Mavis Cosmic Carbone SR's at 1595g, 200g heavier than my existing DA 7850cl's. I love my DA's but wanted a deeper section so have taken the plunge. The question is will they affect performance on hills?

    To find out, both will be shod with conti 4000s and the same inners and will run at the same psi. I am interested to see how the much deeper section mavics (52mm), as opposed to the DA (24mm), will feel and react on:

    1. Short steep climbs (12% plus)
    2. Longer drags (4-9% typical)
    3. My overall times on a standard 60 mile loop.

    My standard loop (the precise route is yet to be decided) will take in the Bwlch and Rhigos or alternatively I will go over the Black Mountain. Whichever way will pick up a number of steep sections and has a good balance of flats, sharp rises and long steady gradients totalling around 1600m of vertical climb over the 60miles.

    IMO I doubt the extra weight will be noticeable, but I am wondering if the rotational factor on a deeper rim uphill may make things different, harder or if it will remain the same. :?: We will find out on Friday !
  • Chris James
    Chris James Posts: 1,040
    How important rotational weight has has been done to death on this forum.

    I recall Chris Juden's response to a simliar question to yours, which quantifies the effect of lighter wheels:

    'The only things that’ll make one pair of wheels climb significantly better than another are better tyres and a bigger sprocket. It seems like you have very nice wheels already, so I really don’t think you’ll be able to justify a new pair on technical grounds.

    Regarding rotating weight: it has been said that an ounce on the wheels is worth a pound on the frame. That’s exaggerated nonsense: concealing however a kernel of truth. When you accelerate, weight at the edge of the wheel not only goes forwards but also goes around at the same speed, acquiring nearly twice as much kinetic energy as it takes to get the rest of the bike moving faster. So an ounce on the wheels is worth two on the frame, but only if it’s in the rim or tyre and only when you’re starting off or sprinting.

    Rotating inertia reduces dramatically as you move away from the edge of the wheel. Even the tyre is not quite worth double, more like an extra 90 to 95%. For the rim it’s 85% or so, spokes 33%, down to less than 1% at the hub. Most other parts of a bike don’t spin fast enough to gain much inertia. Assuming you’re in a low to middling (54in) gear: for pedals you can count an extra 6%, cranks 2%, chainrings and chain maybe 1 to 2%. And remember, none of this matters at all when you’re not accelerating.

    Once you’ve got it moving, a bit of extra mass in the wheels actually makes it easier to maintain a steady speed, by smoothing out the intermittent action of pedalling. (Special wheels have even been made with added rim weights, for races run at constant speed from a flying-start!) This stop-go effect becomes especially pronounced in the high-resistance, low momentum conditions of hill climbing. On extreme gradients the bike nearly stalls and has to be accelerated almost from a standstill with each pedal thrust. A couple of flywheels sound useful, except that when you’re climbing you don’t want extra weight anywhere! Rotating or not, it all has to be carried upwards just the same.

    Aerodynamics become less important as speed drops on a steep hill, with this lifting work taking over as the main energy demand of cycling. Rolling resistance still counts; and the efficiency with which the rear tyre transmits tractive force to the road assumes great importance under low speed, high force conditions. Unfortunately the tractive efficiency of cycle tyres (other than off-road) is an almost unresearched topic. However it’s likely that those which roll easily will also drive efficiently; and nicer tyres are usually lighter tyres, perhaps adding to the mythical powers of rotating weight!
  • Anonymous
    Anonymous Posts: 79,667
    I've had light wheels, aero wheels, light aero wheels.

    Very minor differences except on the flat, where the aero wheels shone. Differences on climbs were in the order of around a few seconds per km at most / about 5-10 watts tops.

    I have raced on Zipp 606 combo but now race on an Open Pro powertap rear and lightweight box section front that's strong.

    I TT with a deep front and disc cover rear.

    Unless you are in a breakaway on a race or TTing I don't really think wheels make that much difference.

    Furthermore I've had an aero carbon frame (Cervelo S2) and a lightweight (sublime to ride) Carbon Colnago yet my best racing result has come on my current aluminium frame with the box section wheels!

    At our level, it's all just for show. In my bitter, humble opinion.
  • Grifteruk
    Grifteruk Posts: 244
    :shock: lots to think about then Chris !

    Think I'll agree with NapD and stick with the first reason I bought em - too look good - and use the old fashioned test that if they look good and feel good, they'll make me feel good and go faster (even if that is only in my own head)!
  • goco
    goco Posts: 35
    Once you’ve got it moving, a bit of extra mass in the wheels actually makes it easier to maintain a steady speed, by smoothing out the intermittent action of pedalling. (Special wheels have even been made with added rim weights, for races run at constant speed from a flying-start!) This stop-go effect becomes especially pronounced in the high-resistance, low momentum conditions of hill climbing. On extreme gradients the bike nearly stalls and has to be accelerated almost from a standstill with each pedal thrust. A couple of flywheels sound useful, except that when you’re climbing you don’t want extra weight anywhere! Rotating or not, it all has to be carried upwards just the same.

    Exactly. Huge misconception this. Heavier wheel requires more effort to get it spinning, but conversely will require (very marginally) less effort to keep it spinning. Going uphill at a constant speed, weight is weight, rotating or not. So, lighter wheels will help you accelerate better (due to less inertia and lower weight) and make you ever so slightly slower on the flat, but will only help uphill due to lower weight - and thats the same whether it comes of the wheel, the frame, or the rider.
  • goco
    goco Posts: 35
    To illustrate the fallacy of the rotating mass argument - you can "feel" rotational inertia by turning your bike upside down and spinning the front with your finger. The effort it takes to spin the unweighted wheel is the rotational inertia (plus a little bit of aero resistance once it starts spinning).

    Then do the same with a lighter wheel - sure its a tiny bit easier to get spinning...... but you're using your FINGER, and you pedal with your legs, which are a bit bigger. Will you feel the difference in inertia? Probably not. But you will feel the 500g difference in weight, rotating or not.
  • sampras38
    sampras38 Posts: 1,917
    NapoleonD wrote:
    I've had light wheels, aero wheels, light aero wheels.

    Very minor differences except on the flat, where the aero wheels shone. Differences on climbs were in the order of around a few seconds per km at most / about 5-10 watts tops.

    I have raced on Zipp 606 combo but now race on an Open Pro powertap rear and lightweight box section front that's strong.

    I TT with a deep front and disc cover rear.

    Unless you are in a breakaway on a race or TTing I don't really think wheels make that much difference.

    Furthermore I've had an aero carbon frame (Cervelo S2) and a lightweight (sublime to ride) Carbon Colnago yet my best racing result has come on my current aluminium frame with the box section wheels!

    At our level, it's all just for show. In my bitter, humble opinion.

    Great post and how true. :lol:
  • Anonymous
    Anonymous Posts: 79,667
    One thing I do notice with lighter wheels is when you do this -

    Hold the hub and spin the wheel (fast)

    Then rock the hub along the horizontal axis simulating the movement when giving it big legs out of the saddle.

    Lighter wheels are much easier to control when doing this.

    Whether or not it has any relevance whatsoever when riding I know not...
  • motdoc
    motdoc Posts: 97
    I have Fulcrum racing zeros. The main reason being the awesome redness (and some good reviews). Having ridden on a wheel with red spokes I can definitely say that red spokes are faster, and that the more red you have nearer the rim the faster you'll go.

    I have also got red stripes on my tyres and yellow caps on my valves, worth at least 7 watts.

    Buy what you want and enjoy buddy! (any excuse is good)
    Arrrrr I be in Devon.
  • pianoman
    pianoman Posts: 706
    So, lighter wheels will help you accelerate better (due to less inertia and lower weight) and make you ever so slightly slower on the flat

    So you saying that Gipiemme Tecno Pro wheels: http://www.shop.kinetic-one.co.uk/gipie ... -487-p.asp

    would be actually quicker on the flat than Campag Zondas even though the Zondas are 300 grams lighter? If so that write-up by Kinetic-1 isn't just marketing dross, it's for real! Do they make ceramic bearings too?
  • Anonymous
    Anonymous Posts: 79,667
    PianoMan wrote:
    So, lighter wheels will help you accelerate better (due to less inertia and lower weight) and make you ever so slightly slower on the flat

    So you saying that Gipiemme Tecno Pro wheels: http://www.shop.kinetic-one.co.uk/gipie ... -487-p.asp

    would be actually quicker on the flat than Campag Zondas even though the Zondas are 300 grams lighter?

    Most likely.
  • pianoman
    pianoman Posts: 706
    But of course don't forget the Veloflex Records and Michelin Latex tubes then........
    Has anyone tried these wheels and found them to go like a rocket? I would have thought 40mm is right on the cusp of wheat you need to start delivering "extra aero efficiency".