Sprint problems

flatface

With the nice new bit of tarmac heading out of Donnybrook towards town, I decided to try my first ever sprint this morning. My eye-popping best effort was way below the 70kph I was expecting - what gives? Do I need a new bike?

Lumen

flatface wrote: »

Do I need a new bike?

http://www.boards.ie/vbulletin/showpost.php?p=73562251&postcount=8870

OldPeculier

Did you have a lead out man? That could be the problem right there

petethedrummer

Is it aerodynamics due to the flatness of your face?

thebouldwhacker

You need to put away your bike and never post here again. The ART forum is for the likes of you.
Shame on you, posting such weakness here should mean instant thread lock.

flatface

Thanks for the help, I cannot afford that super-scott just yet. I have not friends on the morning commute only mortal enemies but perhaps I can use a bus to get up to speed. It was my last attempt at bus drafting that gave me my flat face

But serious like, on the smooth flat out should I not be able to get past 50kmph?

kenmc

flatface wrote: »

With the nice new bit of tarmac heading out of Donnybrook towards town, I decided to try my first ever sprint this morning. My eye-popping best effort was way below the 70kph I was expecting - what gives? Do I need a new bike?

I'd start with a new pair of legs, otherwise a nice new bike will just be a waste.

Beasty

flatface wrote: »

But serious like, on the smooth flat out should I not be able to get past 50kmph?

But you said 70kph, which is ambitious for the flat

It depends on the wind conditions also, but yes, if you're reasonably fit you should be able to get above 50kph on a racing bike. It's unlikely to be the bike that's the problem - much more likley to be lack of fitness/speed on your part;)

Raam

flatface wrote: »

But serious like, on the smooth flat out should I not be able to get past 50kmph?

Depends on the wind and how strong your legs are. With my puny legs, I barely manage 60kph on the flat.

petethedrummer

Cavendish hits 70-74km/h in a finish so that's a bit high to be aiming for.

50 should be handy enough to hit. You may have been on a false flat or into a slight head wind or just tired. I presume you had a rolling start and you weren't going from stopped. If you go from stopped you'll be wrecked well before you hit your max speed.

You've got me curious now as to what speeds I can hit. I'm gonna have to put my comptuer back on my bike.

RobFowl

Raam wrote: »

Depends on the wind and how strong your legs are. With my puny legs, I barely manage 60kph on the flat.

You manage 60kph up the feckin hills as well though

Raam

RobFowl wrote: »

You manage 60kph up the feckin hills as well though

I'm joking btw!

07Lapierre

flatface wrote: »

With the nice new bit of tarmac heading out of Donnybrook towards town, I decided to try my first ever sprint this morning. My eye-popping best effort was way below the 70kph I was expecting - what gives? Do I need a new bike?

Yes! a new bike will solve all cycling problems!

flatface

Beasty wrote: »

But you said 70kph, which is ambitious for the flat

It depends on the wind conditions also, but yes, if you're reasonably fit you should be able to get above 50kph on a racing bike. It's unlikely to be the bike that's the problem - much more likley to be lack of fitness/speed on your part;)

Was being a bit tongue in cheek, but I was surprised by how fast I didn't go. Normally I would be about 35-40 along this stretch so to push it any only get to 50 was ego bashing. If only I hadnt tried, now I must try every day and arrive a sweaty mess to work.

Havent seen much info on good sprint technique, and Cavendish moves to fast for me to see whats going on - do you jump straight to the highest gear and grind or pop up half way long? Should your arms be relaxed or pulling like bejasus?

karlmyson

I like sprinting so I'll offer my tuppence assuming this topic is serious one Speaking as a reasonably competent but non-racing cyclist, when I'm sprinting on the flat in calm conditions, a speed in the mid 50s is what I can expect (and that over 200m-300m at most). With a good leadout and a slight tailwind - again strictly on the flat - I have (only just) exceeded 60kmph once ever - and that only instantaneously. 70kmph on the flat or more is the preserve of the professional, and his team. Wind resistance goes up in proportion to the cube of your speed, and the extra power requirement to get from 60kmph to 70kmph is enormous.

Beasty

Ideally you need to draft a bus - don't get too close though, and look out for the brake lights going on, otherwise you may end up with a flat face ....

Beasty

It's not just sprinting technique though - the fastest I've managed on a flat bit of road was 60.3kph and that was in a TT (although I did have a bit of a tailwind;))

markcroninbsc

My advice is to watch this clip about 200 times. Then get out on the bike and try copy that style exactly, then realise your never goin to make it and give up trying.

https://www.youtube.com/watch?v=iSb_Lj836v4

markcroninbsc

haha this ones funny. this lads gas

https://www.youtube.com/watch?v=CEpIKmWwM0w

flatface

markcroninbsc wrote: »

My advice is to watch this clip about 200 times. Then get out on the bike and try copy that style exactly, then realise your never goin to make it and give up trying.

But it looks so easy? My new plan is to take off the computer for my sprint and concentrate on the form, style and technique of my celebration.

Lumen

Beasty wrote: »

Ideally you need to draft a bus - don't get too close though, and look out for the brake lights going on, otherwise you may end up with a flat face ....

The trick with bus drafting is to hang off the RH corner. That way you still get a decent draft but when the brake lights come on you can just pull out past it.

Passing on the right is legal, so this must be too. :pac:

markcroninbsc

Lumen wrote: »

The trick with bus drafting is to hang off the RH corner. That way you still get a decent draft but when the brake lights come on you can just pull out past it.

Passing on the right is legal, so this must be too. :pac:

YOU NEED TO WEAR A **HELMET** IF YOUR GOINTA DRAFT A BUS

People will think this is from a mod if i do it in bold

RidleyRider

Me and my friend did a lead out sprint a while back. I was leading and got him up to about 60km/hr just slipping down in the gears and in the saddle and as the speed leveled out i got outta the saddle to push in on then got outta the way fot him to go for it, he got 40mph which also is 70km/hr:D

Just practise it and get the raw power into your legs and you'll be grand:D

L'Enfer du Nord

Two points (probably both mistaken!):

Isn't sprinting as much about acceleration as speed? After-all Cancellara isn't a sprinter nor was Boardman, plus while they tend to do well the top sprinters don't usually win even short prologues.

More than anything else isn't sprinting down to genetics?

I've also always assumed that there's no performance enhancing drugs that will turn a non-sprinter into a sprinter - unlike EPO and climbing, (that's not to say that there aren't drug cheat sprinters).

I can't remember anyone becoming a sprinter later in their career, I think of a few who went the other-way to become rouleurs/all rounders - Kelly, Jalabert, - Hushov is going that direction too.

Lumen

L'Enfer du Nord wrote: »

I've also always assumed that there's no performance enhancing drugs that will turn a non-sprinter into a sprinter - unlike EPO and climbing

Ben Johnson might disagree about the benefits of PEDs. I imagine the roid rage could also offer some psychological benefits.

I would guess that to sprint faster you need more fast twitch muscle mass. Steroids and training would presumably do it, but that's going to make you heavier, which would hurt your climbing, and you're still not going to win against a natural sprinter. So what's the point?

Whereas EPO has no performance downside (only the health risks).

kenmc

Steve Marquis wrote: »

40mph which also is 70km/hr:D

SHENANIGANS!

RidleyRider

Its technique, you have to find a way most comfortable and suitable for you:D No need for steroids or anything like that you either have it to be a sprinter or you dont:p

L'Enfer du Nord

Lumen wrote: »

Ben Johnson might disagree about the benefits of PEDs. I imagine the roid rage could also offer some psychological benefits.

I would guess that to sprint faster you need more fast twitch muscle mass. Steroids and training would presumably do it, but that's going to make you heavier, which would hurt your climbing, and you're still not going to win against a natural sprinter. So what's the point?

Whereas EPO has no performance downside (only the health risks).

True, but I'm sure Ben Johnson was always a sprinter, steroids hardly changed him from a middle distance runner into a sprinter. I'm sure steroids can help around the margins, and small margins are obviously important in sprinting.

Lumen

L'Enfer du Nord wrote: »

True, but I'm sure Ben Johnson was always a sprinter, steroids hardly changed him from a middle distance runner into a sprinter. I'm sure steroids can help around the margins, and small margins are obviously important in sprinting.

I've no idea. We need a scrawny volunteer and a skip load of drugs.

Lumen

Ffffffuuuuuuuuu...

petethedrummer

Watch and learn people. Watch. And. Learn.

https://www.youtube.com/watch?v=2lJEslVrLRY

RidleyRider

Why talk about taking drugs? Its illegal in the sport and that link Lumen, clearly says they show up in tests and wasn't there enough controversy over Contador this year in the tour? Natural ability!!!!!!!!

sy

Steve Marquis wrote: »

Why talk about taking drugs? Its illegal in the sport and that link Lumen, clearly says they show up in tests and wasn't there enough controversy over Contador this year in the tour? Natural ability!!!!!!!!

Shame on you Lumen

Pherekydes

karlmyson wrote: »

Wind resistance goes up in proportion to the cube of your speed, and the extra power requirement to get from 60kmph to 70kmph is enormous.

That's a new one on me. Where did you get this nugget?

thebouldwhacker

petethedrummer wrote: »

Watch and learn people. Watch. And. Learn.

She always reminds me of this pedaling pro...... AWESOME

sy

Pherekydes wrote: »

That's a new one on me. Where did you get this nugget?

I think he/she meant the power required increases as the cube of the velocity. Double the velocity then power must increase by factor of 8....

Harrybelafonte

A little off topic, but, do people find they can sprint at greater speeds on rollers?

chakattack

Cav really gets down low and aero over the bars.

Any other side profile sprint videos?

Lumen

sy wrote: »

I think he/she meant the power required increases as the cube of the velocity. Double the velocity then power must increase by factor of 8....

Also, to accelerate you need to overcome inertia, and that increases with the square of velocity.

80kg@60kph, E=0.5*80*16.7^2=11.16 kJ
80kg@70kph, E=0.5*80*19.4^2=15.05 kJ

So to accelerate from 60-70kph in 10 seconds, you would need to generate 389W in addition to the power required to overcome air resistance.

Harrybelafonte

chakattack wrote: »

Cav really gets down low and aero over the bars.

Any other side profile sprint videos?

Can't find the quote now, but one of his fellow sprinters attributed his short stature to his ability to get so close to the bars, which gave him aero advantage over the others.

Esroh

May have been posted before but if you want to study Cav thru bad days and good days with or without his Train this is your syllabus

http://www.youtube.com/watch?v=mxRcaIVPkps&feature=related

victorcarrera

petethedrummer wrote: »

Watch and learn people. Watch. And. Learn.

https://www.youtube.com/watch?v=2lJEslVrLRY

She is awesome and sprinting on a cadence of about 60RPM too.:D

To the OP. Even if you only have a casual interest in this, it would be well worth your while to try out Sundrive road track cycling. [HTML]www.trackcycling.ie[/HTML]
They will answer all your queries in a very short space of time and make you faster too.
You can rent track bikes from them and it is not very expensive to try it out.

levitronix

To sprint really well its a trade off with something else not unless your gifted.
The start of the year i was doing a lot of sprint training and hitting big numbers 1100 watts for 10 secs in training but hadnt got a good FTP and was tried towards the end of races, so i went and trained more FTP stuff and lost the big numbers in the sprints now i dont break 1100 watts that often but with a better FTP get better results.

So im open to suggestions to where to get the right balance

Whats next drugs haha dont think so

thebouldwhacker

victorcarrera wrote: »

You can rent track bikes from them and it is not very expensive to try it out.

hmmmmm

blorg

Harrybelafonte wrote: »

A little off topic, but, do people find they can sprint at greater speeds on rollers?

Lack of air resistance would suggest high speeds would be much easier to achieve, yes.

Harrybelafonte

blorg wrote: »

Harrybelafonte wrote: »

A little off topic, but, do people find they can sprint at greater speeds on rollers?

Lack of air resistance would suggest high speeds would be much easier to achieve, yes.

Thanks. New there was something different going on.

petethedrummer

Cavendish doesn't seem to do that head nodding thing that sprinters used to do.
Loads of it here: http://www.youtube.com/watch?v=E1iaQf7YvMY

12 sprocket

is the reason for the head nodding thing in the older sprints with cippolini because they are sprinting at higher cadences than todays tour sprinters. I presume that they were using lower gears then maybe a 12 or 13 sprockets compared to the 11 that the riders now use.
The cadences seems lower in some of todays sprints.

Bunnyhopper

Esroh wrote: »

May have been posted before but if you want to study Cav thru bad days and good days with or without his Train this is your syllabus

http://www.youtube.com/watch?v=mxRcaIVPkps&feature=related

LOL at Cav's comments on Renshaw at 38m 02s.

petethedrummer

12 sprocket wrote: »

is the reason for the head nodding thing in the older sprints with cippolini because they are sprinting at higher cadences than todays tour sprinters. I presume that they were using lower gears then maybe a 12 or 13 sprockets compared to the 11 that the riders now use.
The cadences seems lower in some of todays sprints.

I would say the opposite, some of them look like they are trying to push bigger gears and have to move the rear half of their body up and down more. For example, if you start off in a too big gear you bounce up and down in order to get up to speed. I dunno though, you could be right. Maybe more arm movement is used nowadays and that negates the need to shift the weight up and down.

Its some contrast between how un-aerodynamic Cipollini was compared to Cavendish.

Also, do the pros actually sprint in 53x11?

Lumen

For the nerds, an interesting graph from a thread elsewhere.