What is Aero actually worth ?

[Gargamel]

Chaps, I know there are some experienced racers on here. So I have a question.

Over a 1 hour TT, what is the effect of various Aero. Is there a definitive scientific research study on

(say)

Solid real wheel

Aero Helmet

Deep rims.

Tri Bars

Etc

Have spanked a 35 km/h for an hour and seen myself beaten by 9 minutes by the top riders, I am wondering,

1. Train harder
2. Throw money at the problem

I was on a old school racer, some of these boys where on full tri TT bikes, Woodies (pecker head helmets) and with solid rears.

[fromage]

http://www.bikeradar.com/road/gear/article/how-aer...

[okgo]

For basic info that link above is good.

But beyond that your position on said TT bike is worth a vast amount, and I do mean vast, far more than any component can give you.

[superkartracer]

One study published in the German Tour magazine Jan 2007

They put Uwe Peschel on a normal bike:

Needed Watts for Speed = 45 km/h :

Stevens San Remo bike with normal handlebar 465 Watts needed to go 45 km/h
Same bike Hands down the drops: 406 watts needed
Same bikeEaston Aeroforce bar: 369 Watts
Same bike Triathlon position (5.5 cm lower bar, saddle forwards): 360 Watts
Same bike Triathlon position (5.5 cm lower bar, saddle forwards) and
carbon Tri spoke wheels front and rear: 345 Watt

Cervelo + Tri spoke front 328 Watts
Cervelo + Tri spoke front + disk rear wheel : 320
Cervelo + Tri spoke front + disk rear wheel +Giro helmet: 317
Cervelo + Tri spoke front + disk rear wheel +Giro helmet + speed suit: 307
Cervelo + Tri spoke front + disk rear wheel +Giro helmet + speed suit +
saddle 3 cm further back: 293 Watts

From 465 to 293 watts... That's a lotta savings.

Loads

PS. If your only doing 21 mph on your RB in racing, work on fitness first i reckon then spend some £££, you need to be around 24-25 mph on a RB first to see the big gains. Was that 21 mph on hoods/drops ??

Edited by superkartracer on Wednesday 26th June 12:29

[rhinochopig]

Interesting link fromage, but - and I did just skim it so may have missed it - it doesn't seem to factor in mass. I would be interested to know what effect that has, as a TT bike is typically a chunk heavier than a similarly priced road bike. So does the aero benefit on the flat bits outweigh the increased climbing performance on the hills that a road bike offers.

I'm doing a team half iron-man at the weekend in the lakes on a VERY hilly route and am curious whether I'd be theoretically better off on aero bike than on a road bike.

[Gargamel]

Hoods mostly - my current steed is probably a size too small for me ideally.

[superkartracer]

rhinochopig said:

Interesting link fromage, but - and I did just skim it so may have missed it - it doesn't seem to factor in mass. I would be interested to know what effect that has, as a TT bike is typically a chunk heavier than a similarly priced road bike. So does the aero benefit on the flat bits outweigh the increased climbing performance on the hills that a road bike offers.

I'm doing a team half iron-man at the weekend in the lakes on a VERY hilly route and am curious whether I'd be theoretically better off on aero bike than on a road bike.

1-2 kg? makes little difference and if that bothered lose some weight.

[superkartracer]

Gargamel said:

Hoods mostly - my current steed is probably a size too small for me ideally.

Get yourself on the drops, saves around 40/50 watts and gains you 1+ mph, get them as low as poss so your legs smash into your chest and you can't see, great fun

There ya go, free speed.

[okgo]

rhinochopig said:

Interesting link fromage, but - and I did just skim it so may have missed it - it doesn't seem to factor in mass. I would be interested to know what effect that has, as a TT bike is typically a chunk heavier than a similarly priced road bike. So does the aero benefit on the flat bits outweigh the increased climbing performance on the hills that a road bike offers.

I'm doing a team half iron-man at the weekend in the lakes on a VERY hilly route and am curious whether I'd be theoretically better off on aero bike than on a road bike.

Remember that most TT's are not that hilly, so it doesn't matter. 2kg on the flat makes almost no difference hence heavy discs etc.

Up steep hills weight more important, but only you can decide whether the little bit of extra weight it worth it. If the course has a lot of flat in it, or the inclines are steady I'd be on a TT bike every time.

[Gargamel]

Interesting topic.

I guess I need to rent a tri bike and see if I can live with the riding position. Sadly I don't have £££ to throw at bikes.

24 minutes over 180km is certainly well worth thinking about.

[rhinochopig]

Cheers Okgo / SKR. I'm a mountain biker really so for me it's academic, but I just wondered given the race I'm doing is part of a half IM - I agreed in the pub to ride the cycle leg so some friends could do the swim and the run legs - whether many would be doing it on TT bikes, given they're usually the bike of choice for Tri's. IIRC you go over one of the nasty passes and over the top of Shap Fell so it is pretty lumpy.

ETA: Interesting benefit of riding on the drops though - would never have thought it made such a difference. Will have to adopt that at the weekend if my back will cope.

[superkartracer]

And ( if you have the balls/mental ) that in the tuck the TT bike could hit 50mph down the other side, much faster than your RB, but than you might die also ha ha

[rhinochopig]

superkartracer said:

And ( if you have the balls/mental ) that in the tuck the TT bike could hit 50mph down the other side, much faster than your RB, but than you might die also ha ha

Being a mountain biker and a big lump to boot, that is where I hope to gain some ground back; when gravity has stopped hating me on uphill bits.

[okgo]

rhinochopig said:

Cheers Okgo / SKR. I'm a mountain biker really so for me it's academic, but I just wondered given the race I'm doing is part of a half IM - I agreed in the pub to ride the cycle leg so some friends could do the swim and the run legs - whether many would be doing it on TT bikes, given they're usually the bike of choice for Tri's. IIRC you go over one of the nasty passes and over the top of Shap Fell so it is pretty lumpy.

ETA: Interesting benefit of riding on the drops though - would never have thought it made such a difference. Will have to adopt that at the weekend if my back will cope.

You'll never believe how much the body slows you down. I compare myself against a dude in my club who produces much less power than me, our positions on the bike (tt bike) look similar, yet he needs 30-40w less than me to go the same speed.

[Gargamel]

so why don't road racers always use aero? is it in the regs, or is it due to peloton or is it a cultural thing?

[okgo]

They often do, as long as stage isn't up in high mountains?

[PaulG40]

okgo said:

You'll never believe how much the body slows you down.

Having just switched from a light mountain bike to a road bike, albeit a hand me down Carrera, I simply can't believe the difference in ease and speed. Even riding in wind was a killer and I hated it. Now, I jut get on and go. Same again, since using the drops alot more, just have more energy left

[Rouleur]

Gargamel said:

so why don't road racers always use aero? is it in the regs, or is it due to peloton or is it a cultural thing?

They're not allowed on road stages as it would be very dangerous, only in TTs.

[nottusleinad]

superkartracer said:

And ( if you have the balls/mental ) that in the tuck the TT bike could hit 50mph down the other side, much faster than your RB, but than you might die also ha ha

You can hit 50mph in the drops on a RB too, with a 50x11

[yellowjack]

nottusleinad said:

superkartracer said:

And ( if you have the balls/mental ) that in the tuck the TT bike could hit 50mph down the other side, much faster than your RB, but than you might die also ha ha

You can hit 50mph in the drops on a RB too, with a 50x11

http://goo.gl/maps/JlUzY ...53mph flat out - steel frame running 53x12. 46mph on aluminium roadie with 50x11. Believe me, I've tried to get it up to 50mph on the 'best' bike but either I, or the machine, seem incapable of matching the speed of a younger me on a heavier bike. Tucked in as small as I could get, and pedalling like a loon.