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Race wheels

Hi. I have the age old problem of bike gear wants/needs.

I have a very nice carbon tri frame, nice ultegra/dAce Gset and until this season the same wheels I have raced in for four seasons. I have a good training regime of about 6-7 hrs a week, brought down my 5 and 10 k run pace, swim is still nice at just under the hour for 3.5k. My last tri which included an undulating bike course was done at an avg of just over 20mph/ just over 30kph.

I am quite slight at 140lbs/64kg and don't have hams for thighs.

My confusion is to wheel weight. I have a trusted pair of 2001 ish shamal 16 spoke tubs. W/skewers and conti comp tires they weigh 1600 gr and 1200gr rear and front, kitchen scales. I am aware that you get what you pay for, however just weighed my cpx33 front spare w/skewer and conti wet tyre and that comes in at 100gr heavier at 1300g.

I am looking for lighter deep rim wheels, they will be old 404's or planet x's off eBay for under 200ish hopefully.

Is it worth it?


  • There are a number of factors which affect how a wheelset performs with the course being highly significant.

    The first factor to put things in perspective is rolling resistance, or energy lost between the interface of the road and wheelset. The quality of a tyre/tubular plays a significant part here, and narrow widths and super high pressures are not the be all and end all as there is a point where the tyre stops rolling and begins to bounce/vibrate loosing energy. Rider weight and quality of road surface being determining factors. The vast majority of set ups could be significantly improved here.

    The next point is wheel rigidity or how much energy is lost through lateral flexing. For riders with greater weight/strength this can be significant especially when out od the saddle with the rider bikes centre of gravity moving across the wheel line a flexible wheel will absorb this energy which is lost, thought this might make the ride more comfortable.

    I would then say that all weight is not equal. Weight on the rim is far more significant than weight on the hub as it obviously has to move through a greater distance and it takes effort to do so.

  • To back up my final point a bit how come we have not really seen significant improvements in road time trial records with the advancements in wheel design over the past twenty years, as some of these records were set with pretty heavy disk wheels?

    The answer is it takes a lot more energy to get a wheelset up to speed than it does to keep it there. In the case of these old times once a heavy disk wheel was rotating if the rider could prooduce the energy to keep it spinning the weight is no real disadvantage, rather like a heavy flywheel on a steam engine it helps to even out slight variations in the riders output.

    The problems come when the rider has to add more energy into the equation to overcome things like gradients or when the output is disrupted when they have to brake into a bend and the accelerate the wheel back up to speed.

    In answer to your question getting a lighter wheelset might not be justified at all in terms of weight if the courses you ride do not require this approach. A more aerodynamic wheelset possibly as you are riding at a speed which this will play a part, at lesser speed not so much.

    If you ride a lot of hills or technical courses then acceleration charecteristics become a factor, on steep hill you are accelerating all the time to overcome the forces of gravity, in this case weight is 'the ' critical factor to performance and not aerodynamics as you are not going fast enough.

    The pros solve the problem of course by having multiple wheelsets none intrinsicly better than the others, and top riders even swap them mid stage at times. Horses for courses as they say.
  • Lancsrider, thanks for the most complete answer I have read on wheels since getting lost in a page of sheldonbrowne.

    I have made up my mind. Keep my trusted shamals for the flatish courses (cotswold113) get a lighter not so aero pair zipp 202'esque for the hills (alpez d'huez)

    Thanks all, have a great season.
  • nivaghnivagh Posts: 595
    I would choose aero over light, within budgetary constraints. Saving 100g on a wheelset is IMO pretty irrelevant given that you're going to be carrying at least that weight in water in your trisuit, and if you're carrying half a litre of drink, that's another half kilogramme...
    Unless you're truly a weight weenie, don't worry about the 100g, just make sure you have a poo before you race
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