Wheel Energy

[runninboy]

I don't know if wider is better or faster
all i know is my favourite rim is the Sigma Pave and i will never part with them
ps i think they are 22mm wide

 

[oldborn]

It makes me laugh at all the bashing on the wide rims (buy 1 person). If it is such a fad then how come it changed the entire bike industry in 2007?

The same people/companies that mocked us going wide miraculously "re-invented" their entire wheel line shortly after we did .......ie, wider rims. Now this is all you see. Numerous magazines have data showing how much faster wider rims are compared to the narrow rims. VeloNews Sept 10 mag. The fastest wheels were wide rim wheels.

Numerous teams are getting provisions in their contracts to ride wide rim wheels from other companies because their wheel sponsors do make wide rims yet. There must be a reason for that. Oh yeah, they are fast!

Just because you (again, talking to 1 person) dont believe in something doesn't give you the authority to bash/ban people or bad mouth companies that support this design ...... a design that is going to be here for a long time.

Have a great weekend

Hey don t go away, HED is best and fastest wheels ever built, please send me one pair and you are going to have first pair in Balkans ever, what a marketing.

I find those posts of producers like HED and Cervelo co-owner guy very pathetic.

Would you really want to make us happy, cut yours prices dude, instead crying for bad posts. You are making yours companies silly.

I wonder would Tullio Campagnolo if he allive act that way. Respect dude.

 

[Boeing]

well all I know is I am running a velocity p35mm rim on my 29er with a Ardent 2.4 tubeless and down to about 20-21 psi. and I am never looking back

 

[Notso Swift]

Good one RDV, idiots baiting need to be banned, he could have done so much with rational arguments instead of actually getting people to shut down to his arguments

Sorry but the base article is crap, most likely because the information has not been given and/or the need to reach editorial format. There are way to many variables that haven't been looked at, or, more likely they have but have been standardised out of calculations, when you can't actually do that

All of a sudden, aero, the most important thing we have to beat at even moderate speeds doesn't count. 21 to 25 is almost 25% wider.
A 25 may be better on a 23mm rim, but what about a 25 on a 19mm rim where there is the double wammy where the side wall must flex more as it is forced into a trapezoid section, the Peanut profile is not something I have seen in any research as being desirable...
Wide offer less resistance all other things being equal... except on my 21 mm single I can pump it up a full 40 psi more than the 23 from the same manufacturer, things are not equal

 

[ElChingon]

The wider rims aren't so much about aerodynamics as they are handling. The selection of 20mm clincher tires is becoming less and less, you just named two of the biggest names in wheels, HED and Zipp, Velocity also mfg's the A23. Some are going with a 22mm wide rim like Easton and C-4. Who was that auto mfg that advertised wider is better? Dodge? As much as I hate snake oil salesmen of the ad world there is some actual truth to this claim, and it does relate to our wild wacky world of cycling.

Well I think the whole wider rim and wider tire makes sense as much as narrow rim narrow tire do as well, same aero advantage as the turbulence listed won't form as long as there is no big gap between the two.

As for handling, I don't see a difference unless you mean 20mm tires tend to track like train rails which I think is the way to go, I hate that flex when you stand on wider tires. The pros probably want a wider rim for the cobbled races where they use wider tires, that makes sense as they should go together.

The for 20mm tires, am I the only one who can find them? Maybe I should stop stock piling them, then maybe the rest would find them still in stock . As for flats I think I have never flatted on a 20mm tire, or can't remember, as removing those are a chore and I'd remember if I had to.

For the snake oil, I think its really up to everyone's personal riding preference, some like the stiff feel, some like the softer feel which is why I wish the variety should stay and not have a universal size on things like tires and rims.

Too bad the story didn't include any data (hint to the story writer), which is what makes it all to snake oil-ish to begin with.

 

[RDV4ROUBAIX]

Well I think the whole wider rim and wider tire makes sense as much as narrow rim narrow tire do as well, same aero advantage as the turbulence listed won't form as long as there is no big gap between the two.

I will agree that it's more efficient aerodynamically to have rim and tire width as close as possible, but if someone is riding 23mm tires on 20mm rims, that "turbulence" is well, let's just say it looks more severe in the diagram than what's actually happening in real world applications.

As for handling, I don't see a difference unless you mean 20mm tires tend to track like train rails which I think is the way to go, I hate that flex when you stand on wider tires. The pros probably want a wider rim for the cobbled races where they use wider tires, that makes sense as they should go together.

Wider tires handle better because the contact patch is covering more surface area and doesn't give up rolling resistance to a smaller tire. Look at most all motorsports tires and rims, .... wider

The for 20mm tires, am I the only one who can find them? Maybe I should stop stock piling them, then maybe the rest would find them still in stock . As for flats I think I have never flatted on a 20mm tire, or can't remember, as removing those are a chore and I'd remember if I had to.

They're still readily available (20mm tires), the majority of all the tire choices are for 23's though, and the only people who I ever see using those 20's are for TT and tri events,, and you.

For the snake oil, I think its really up to everyone's personal riding preference, some like the stiff feel, some like the softer feel which is why I wish the variety should stay and not have a universal size on things like tires and rims.

If enough wheel mfg's go with the wider rims, and it looks like the wind is blowing in that direction, you'll see the 23mm wide rim as the new standard in lightweight race wheels, clinchers and tubulars

Too bad the story didn't include any data (hint to the story writer), which is what makes it all to snake oil-ish to begin with.

You should write Wheel Energy and ask for the numbers, they're awfully small numbers to be even worried about in the first place, which is why most of this thread is about handling and useless aero differences, neither of which was discussed in the story.

 

[Notso Swift]

Wider tires handle better because the contact patch is covering more surface area and doesn't give up rolling resistance to a smaller tire. Look at most all motorsports tires and rims, .... wider

\

Actually the contact area/surface area is identical, where weight and pressure is the same

The narrower tyre, however, will have a smaller surface area as it is typically inflated higher!

And as an aside from a lot of motorsport experience a wider tyre is not always faster

You need too look at the total effect of drag against the need for lateral grip

More commonly the same question in wings and slicks formula with a controlled tyre (like F1) the equation is expressed drag vs downforce, However should the downforce be the constant and the tyre uncontrolled...

How much tome do you lose due to cornering vs straight line drag? The answer is entirely dependent on the rider and course, a rider will always be faster on narrower tyres provided they do not demand more lateral grip than available, or even if they do they will be faster provided the total lost is less than the opportunity cost

 

[RDV4ROUBAIX]

Actually the contact area/surface area is identical, where weight and pressure is the same

How is that possible? Given the same pressure and rider/bike weight, a 25mm tire is going to have a wider contact patch over a 20mm tire, especially when mounted to a wider rim like what we've been talking about

 

[BroDeal]

How is that possible? Given the same pressure and rider/bike weight, a 25mm tire is going to have a wider contact patch over a 20mm tire, especially when mounted to a wider rim like what we've been talking about

In an ideal model the contact patch will only depend on the tire pressure and the weight the tire is supporting. The real world is not ideal...

 

[Black Dog]

How is that possible? Given the same pressure and rider/bike weight, a 25mm tire is going to have a wider contact patch over a 20mm tire, especially when mounted to a wider rim like what we've been talking about

The narrow tire will deform more than a wide tire under the same pressure and should have a similar contact patch. However, this increased deformation will create a lot of rolling resistance. Thus the narrow tires need more pressure to roll fast and have a smaller contact patch, at higher pressure. They give a harsher ride and go slower when the road gets bumpy because they can not absorb the bumps and instead lift the bike and rider over them sapping momentum in the process.

 

[RDV4ROUBAIX]

In an ideal model the contact patch will only depend on the tire pressure and the weight the tire is supporting. The real world is not ideal...

I'm starting to believe that, same thing can be said for all the aerodynamic hoopla about tires. If only we all rode in wind tunnels all day, instead of in our less than ideal world.

Rode up Lookout Mountain in Golden CO last weekend and the wind direction changed about a hundred times in 30 min. Now that's not ideal!

 

[xmoonx]

The "puncture" claim relates to pinch flats when you have a 23mm wide rim capped with a 23mm tire. The sidewall is less apt to deform in this configuration because the wider rims are spreading out the tire and the sidewall isn't hanging over the rim edge, the result is less pinch flats and better handling.

Suppose if you're rolling 20's you have a 3mm buffer over a 23mm tire. That's a small margin if there ever was one. No matter what width tire you're riding, if you run over something sharp enough you're going to flat.

Although you can use practically any tire/rim combination that shares the same bead seat diameter, it is unwise to use widely disparate sizes.
If you use a very narrow tire on a wide rim, you risk pinch flats and rim damage from road hazards.

If you use a very wide tire on a narrow rim, you risk sidewall or rim failure. This combination causes very sloppy handling at low speeds.

 

[xmoonx]

Useful link on rolling resistance

http://smtp.schwalbetires.com/tech_info/rolling_resistance

 

[RDV4ROUBAIX]

Although you can use practically any tire/rim combination that shares the same bead seat diameter, it is unwise to use widely disparate sizes.
If you use a very narrow tire on a wide rim, you risk pinch flats and rim damage from road hazards.

If you use a very wide tire on a narrow rim, you risk sidewall or rim failure. This combination causes very sloppy handling at low speeds.

So all those years of riding sometimes up to 38mm tires on 19mm wide rims I must have been completely out of my mind? I suppose the better question would be, why are you telling me this?

 

[Notso Swift]

How is that possible? Given the same pressure and rider/bike weight, a 25mm tire is going to have a wider contact patch over a 20mm tire, especially when mounted to a wider rim like what we've been talking about

Yes it is wider, but it is also shorter, the contact patch (mm2 or whatever you wish to use) is identical

 

[biketechreview.com]

wind tunnel testing and tires

from an aerodynamic perspective, it's been my experience that the tire you choose can be more important than the wheel...i.e, you can ruin the aerodynamics of an expensive TT wheel with a poor performing $75 tire.

 

[GreasyMonkey]

RDV, I have not come across these wide rims that are discussed - I assume that all of the discsussion is only relevant to clinchers, not tubs, as the rim bed for a tubular is not going to impact the effective tyre width, to my understanding & experience.

Am I correct on this?

I am an old-fart when it comes to rubber - Veloflex tubulars (Roubaix, Carbon & Record for TT's).

 

[RDV4ROUBAIX]

RDV, I have not come across these wide rims that are discussed - I assume that all of the discsussion is only relevant to clinchers, not tubs, as the rim bed for a tubular is not going to impact the effective tyre width, to my understanding & experience.

Am I correct on this?

I am an old-fart when it comes to rubber - Veloflex tubulars (Roubaix, Carbon & Record for TT's).

It all started with HED a couple years ago, I think just about every wheelset they offer now is 23 wide clincher and tubular. Velocity has the A23 clincher and Major Tom tubular, both 23 wide. Zipp Cyclocross versions of the 303 and 404 tubulars are 25.4 wide, so I I'd say the benefit of a wider tubular is valid. Little more to cradle the tire, makes sense after riding countless years of 19mm rims with 32 and 35mm cross tubulars.

 

[GreasyMonkey]

RDV, Thanks, it makes sense for the cyclocross application.

Would not like to think of riding a 32mm tub balancing on a 19mm bed......

 

[biketechreview.com]

It all started with HED a couple years ago, I think just about every wheelset they offer now is 23 wide clincher and tubular. Velocity has the A23 clincher and Major Tom tubular, both 23 wide. Zipp Cyclocross versions of the 303 and 404 tubulars are 25.4 wide, so I I'd say the benefit of a wider tubular is valid.

the H3 is narrow. And even twenty years or so after its release, it is still tough to beat.

 

[RDV4ROUBAIX]

RDV, Thanks, it makes sense for the cyclocross application.

Would not like to think of riding a 32mm tub balancing on a 19mm bed......

Well, they're still doing it that way even a the highest levels. Not every mfg has caught on to wider rims yet. That's all changing in the next couple years, even for road use.

.... I should add too that 19-20mm wide rims, clinchers and tubulars aren't going away, here to stay.