sportive bikes: is it more than just upright riding position

It's a marketing term. Used currently to describe a bike with a longer head tube than normal which means the bars are higher thus giving a more upright riding position. I saw some guy out on such a bike on Saturday and he looked like a praying mantis as his bars were so high!

A bike needs to be stiff to allow the transfer of power from your legs, through the drivetrain into forward motion. The stiffer the bike the more power is transferred. However, a bike can be too stiff and thus uncomfortable to ride as it doesn't soak up the bumps and uneveness in the road. Compliance describes a bikes ability to absorb these.

Due to the wonders of carbon fibre manufacturers now seem able to build a bike that is laterally stiff, and transfers power efficiently, but compliant vertically so it remains comfortable to ride.

Hi. As far as we at Sunday are concerned, it is of course a marketing term. Marketing term means a sales term, but to be fair its also about giving a certain profile of customer a product that's likely to suit them.

We market the Silk Road as a sportive bike. We consider a number of factors that make it's design suited to the sportive user and to the sportive event. Heres a quick run down:

Longer head tube - because a sportive event will probably take a minimum of 6 hours and the 'typical' sportivist is relatively new / revisiting teh sport after a lay-off, 35+ years old and therefore wants something that's a comfortable riding position for a long day out and isn't actually interested in being in a cramped race position at all.

Shorter Top tube - For the same reasons listed above, we noticed that people on traditional geometry race bikes but using them for sportives were running shorter stems - to achieve a comfortable reach position. But a short stem can mean dodgy handling. So we shortened teh top tube of the bike, allowing for a decent length stem to be fitted, so that the rider is avoiding a stretched out position but gaining from the better handling of a longer stem.

Semi compact geometry - Again, a sportive event is a long day out. The rider will want to carry two large bottles, as well as having room for other bits n bobs. Particularly on small frame sizes, compact frames struggle to accomodate two large bottles. So we designed semi compact, so that you've got that as well as the benefits of lighter weight and greater lateral stiffness associated with the compact geometry.

Measured stiffness - lateral stiffness and some verticle compliance, particularly in the rear triangle. We achieve this in Ti by selecting carefully the most suitable tube profiles.

Finally, other user requirements. Riders making forrays into Europe and beyond to 'bag the marmott' or the etape or a grand fondo or whatever is becoming really popular. So it sdoesn't take much to spot these users will be wanting to load their bikes onto aeroplanes... and therefore be at the whims of baggage handlers. We make in ti because it'll take a good few knocks... but we also DONT make with the currently fashionable integrated seast post / tube because obviously it can be awkward to fit into a bike box... We're currently designing a TT frame that does do this...

Anyway, there are the basics of what we take into consideration on either custom geo bikes and when we designed the Silk Road.

Greg

Pirahna wrote:

andyp wrote:

It's a marketing term. Used currently to describe a bike with a longer head tube than normal which means the bars are higher thus giving a more upright riding position.

IIn my opinion it's a marketing term used to describe a bike with a proper length head tube. The current trend for compact frames and integrated headsets has allowed people to make bikes with short head tubes.

For lots of people it might well be better yes. I personally really dislike tall headtubes. I find they handle poorly ... perhaps due to the greater flex in the headtube or due to hand position being so far from wheel? No idea. They just feel rubbish IMO. They also look rubbish - again a personal opinion!

andyp wrote:

Due to the wonders of carbon fibre manufacturers now seem able to build a bike that is laterally stiff, and transfers power efficiently, but compliant vertically so it remains comfortable to ride.

Due to the wonders of marketing, frame manufacturers manage to convince you that their frame is compliant vertically when it is still a triangulated truss like all other frames, hence a lot stiffer that way than laterally (which is a direction you don't want it to flex in). Possible methods include letting 1psi out of the tyres, which makes more difference than between the stiffest and flexiest frames in a vertical direction. Alternatively carefully design in a small amount of lateral flex, since that will convince the user that their frame is flexing in all directions and so is more comfortable.

aracer wrote:

Due to the wonders of marketing, frame manufacturers manage to convince you that their frame is compliant vertically when it is still a triangulated truss like all other frames, hence a lot stiffer that way than laterally (which is a direction you don't want it to flex in). Possible methods include letting 1psi out of the tyres, which makes more difference than between the stiffest and flexiest frames in a vertical direction. Alternatively carefully design in a small amount of lateral flex, since that will convince the user that their frame is flexing in all directions and so is more comfortable.

Have you ridden a recent carbon frame? I have, a Casati Marte. I also own a Colnago C40 and the Marte is stiffer than the C40 and just as comfortable. The C40 feels dead in comparison. I've run with the same wheels and the difference remains.

aracer wrote:

andyp wrote:

Due to the wonders of carbon fibre manufacturers now seem able to build a bike that is laterally stiff, and transfers power efficiently, but compliant vertically so it remains comfortable to ride.

Due to the wonders of marketing, frame manufacturers manage to convince you that their frame is compliant vertically when it is still a triangulated truss like all other frames, hence a lot stiffer that way than laterally (which is a direction you don't want it to flex in). Possible methods include letting 1psi out of the tyres, which makes more difference than between the stiffest and flexiest frames in a vertical direction. Alternatively carefully design in a small amount of lateral flex, since that will convince the user that their frame is flexing in all directions and so is more comfortable.

You must have a bloody accurate gauge on your pump; not to mention the fact that you're talking bollox

aracer wrote:

Care to expand your position with slightly more words than the one you use at the end there? I'm prepared to defend my position, can you support yours, and explain why the frame breaks the laws of physics and flexes at least 1% of the amount the tyres do?

You're talking nonsense.
!% of frame flex is not equal to 1psi reduction in tyre pressure or whatever it is you're trying to claim.

"the frame breaks the laws of physics and flexes at least 1% of the amount the tyres"

Did I say that. Whatever you think that means?
No, I said or more precisely what I meant was that 1psi reduction in tyre pressure wont make one jot of difference to the handling characteristics or feel of of a bike .

Anton de Lacey wrote:

1psi reduction in tyre pressure wont make one jot of difference to the handling characteristics or feel of of a bike .

On the same basis, changing the frame won't make a jot of difference to the vertical compliance (since the difference between standard frames is less than 1psi in the tyres).

You still don't actually understand the point do you, Anton?

aracer wrote:

Anton de Lacey wrote:

1psi reduction in tyre pressure wont make one jot of difference to the handling characteristics or feel of of a bike .

On the same basis, changing the frame won't make a jot of difference to the vertical compliance (since the difference between standard frames is less than 1psi in the tyres).

What's a standard frame?

aracer wrote:

Double diamond, UCI compliant that you can buy in a shop.

So if you don't understand the point, why are you trying to argue that it's wrong?

(since I wouldn't expect anybody on here to understand my username - it doesn't mean what you think - I'll ignore the ad-homs)

Why are you trying to argue a point that is baseless.

Let's just have a little recap here

"Possible methods include letting 1psi out of the tyres, which makes more difference than between the stiffest and flexiest frames in a vertical direction"

Apropos your user name. You callin' us thick or summat?

Anton de Lacey wrote:

Why are you trying to argue a point that is baseless.

On what basis is it baseless?

re my username - nothing directly to do with cycling.

aracer wrote:

Double diamond, UCI compliant that you can buy in a shop.

So if you don't understand the point, why are you trying to argue that it's wrong?

(since I wouldn't expect anybody on here to understand my username - it doesn't mean what you think - I'll ignore the ad-homs)

So a bike is a bike. The geometry is irrelevant ,the frame material is irrelevant ,the BB height is irreleveant provided the seat is far enough behind it to comply with the UCI regulation.etc . It's all down to tyre pressure ,give or take 1 psi.

Aw bless .Do all your bikes depend on you?

No I don't understand your point as I have said more than once. I understand what you are trying to say but disagree.
I am not the least bit Het up,as Olga here will testify.Well not right now she's busy.
Sorry what was the question again? :?