Wheel Performance

[SpokeyDokey]

I have read a lot over the last year of the need for "better", "lighter". "faster" wheels. I have read about riders getting up to speed faster, beating PB's and storming up hills faster than ever after fitting new wheels.

I have the stock wheels on my Giant TCX1 and with some RS30's on (brake testing for noise) which are supposed to be "better" than my stock wheels I noticed no performance difference apart from a whooshing noise from the spokes on the front wheel - as an aside the sound was annoying really.

All I have read is anecdotal so is there any hard evidence that lighter wheels make you accelerate faster or give you a higher top speed etc?

 

[potsy]

I'm hoping to find out the answer soon SD, about to upgrade from a 2kg wheelset to a 1650g one.
The RS30's are quite heavy at almost 2kg (I use the RS20's)

 

[Mr Haematocrit]

Do the math

Interesting experiment into this
http://www.training4cyclists.com/how-much-time-does-extra-weight-cost-on-alpe-dhuez/

 

[SpokeyDokey]

Do the math

Interesting experiment into this
http://www.training4cyclists.com/how-much-time-does-extra-weight-cost-on-alpe-dhuez/

Ok I read the link.

So about 1.8Kg at the rim (or technically just beyond the rim) cost the rider a tad over 4% lost time. Have I got that right?

Also looking further down at the comment by Beebee the energy expenditure % differences are tiny. Have I got that right?

 

[SpokeyDokey]

[QUOTE 2476434, member: 30090"]Its physics.

Lighter wheels which have a rotational force take less effort to power.

Generally speaking as well they tend to be a lot stiffer for better power transfer.

Ride with some high end mavic or fulcrum wheels and you'll notice a difference.

My personal favourite ars ksyrium sls, beautiful wheels.[/quote]


I have read similar before.

What I really want to know is just how much difference it really makes in the real world.

 

[Mr Haematocrit]

Ok I read the link.

So about 1.8Kg at the rim (or technically just beyond the rim) cost the rider a tad over 4% lost time. Have I got that right?

I have no idea, my maths is terrible..... that's why I advised you to do it that is the appropriate calculation though.
My own experiences make me believe I am consistently faster on deep areo wheels, while I find I climb better on my light shallow rims which are super stiff. I consider a light wheel set to be in the range of 1370 grams a set.

I can't provide any real evidence for my beliefs though

 

[malcermie]

I have read similar before.

What I really want to know is just how much difference it really makes in the real world.

Not as much as losing 2kg of your middle!!!!

 

[goody]

So a 4% improvement when his wheel weight is reduced by 1.8KG, is that right? I think the biggest benefit is psychological. I'd still buy the best wheels I could justify. I wouldn't expect them to make me faster just feel better!

 

[SpokeyDokey]

[QUOTE 2476484, member: 30090"]Dunno.

Sometimes its not about performance but rather a wheel you can fit and forget and gives you a good ride.

Over 6000 miles, only had the rear wheel trued twice and front once. Its all good[/quote]


Yes, I understand you. A problematic wheel is a wheel to forget!

 

[SpokeyDokey]

So a 4% improvement when his wheel weight is reduced by 1.8KG, is that right? I think the biggest benefit is psychological. I'd still buy the best wheels I could justify. I wouldn't expect them to make me faster just feel better!

I thought it was 2 mins over 50 mins = 4%.

Doesn't matter though whether it is 2% or 4 % as basically the equivalent of a whole additional stock wheelset weight at the rim gives (according to that test) a not exactly huge increase in time ditto the extra energy expended in the follow up dialogue.

So typical wheelset weight reductions of 30g, 100g or 200g etc are not likely to make a whole lot of performance difference in the real world?

 

[Rob3rt]

The difference a set of wheels makes to your ride will depend on what characteristics the wheel has and if they suit the type of riding you do. For example, a set of super light, low profile carbon climbers wheels will not really benefit a time trialist and a set of super deep aero rims won't benefit a climber!

 

[Rob3rt]

Oh BTW, when you are talking about 2-4% savings (I don't care to validate your calculation as it doesn't matter to my point, but question the conclusion you reach based on whatever numbers you return), depending on who you talk to, they may tell you that is a massive saving! It is not really all that marginal! Especially if you happen to be pretty quick!

 

[SpokeyDokey]

Oh BTW, when you are talking about 2-4% savings (I don't care to validate your calculation as it doesn't matter to my point, but question the conclusion you reach based on whatever numbers you return), depending on who you talk to, they may tell you that is a massive saving! It is not really all that marginal! Especially if you happen to be pretty quick!

Yes, I see what you are saying there. A 1% better/worse performance change may be a lot to some people but not to others depending on their perspective.

 

[goody]

The 4% savings in the example are from a much larger weight saving than you would get if you start with a decent bike then upgraded the wheelset. It's also over a climb up Alpe D'Huez over normal terrain the improvements might not be so large.