I’ve been pondering this for a while with no real answer

Is it that road sprinters stand as they accesss a higher gear?

Or that a road sprint is shorter

Or is that track sprinters are so much faster that aerodyanimcs are more important

Track sprinters stand to accelerate so do road riders. But road racers are still accelerating as they cross the line?

Cadence?

Track riders are fixed so at full speed I imagine they need to spin a little which is hard stood up?

Road riders can shift up a gear and keep the power through standing?

A bit of googling confirms that Chris Hoy’s gear would be about 100 inches, Mark would have access to a higher gear than that

Would Chris be better off in a bigger gear if he could use a rammp to start…

cadence and distance

Christ Hoy can use a ‘ramp’ start….

The slope of the track…

Standing and sprinting isnt very efficient.

If Chris Hoy sprinted stood up all the way round the track he’d be knackered far quicker. He’s got to support his body weight with his arms and legs rather than the saddle.

It’s cadence, you can’t spin as quick standing up as you can sitting down. If you have gears, you stand and smash a bigger gear. If you’re fixed, most of the time you sit and spin yourself into a heart attack.

If Chris Hoy sprinted stood up all the way round the track he’d be knackered far quicker. He’s got to support his body weight with his arms and legs rather than the saddle.

Not if he was GW he wouldn’t, he never sits down 😛 Hoy’s just lazy and needs to work on his core strength.

On a related note Hoy has more mass, and has to support that weight through the banked corners which adds centripetal forces to his weight, so he’s probably working 30% harder just staying upright than Cav.

Cheers folks

It’s cadence
and aerodynamics, of course.

i’m with the above. deffo cadence. despite his enourmous gear.

he stands to get up to speed, then sits and spins/mashes while sat down to the finish.

Cadence + size of gear available as others have said.
You just can’t stand up when you are spinning your cranks at 140rpm or some other big number on the track.
Hoy might be spinning a 100″ gear in the sprint while Cav might be pushing a 53×11 126″ gear or bigger, plus it might be uphill or have a headwind etc – so = lower cadence hence being able to push it round by standing up in that final sprint for the line.

Yeah I think it’d be cadence and aerodynamics, most of the resistance at that speed will be air friction.

But why does Cavendish use such a massive gear? When he moves through the pack, you wouldn’t say he was spinning at all. In BMX racing it’s spin to win, top guys are doing 180+rpm stood up, Cav looks like he’s doing half that. If power is a function of force x speed, in my head he could be going even quicker with an easier gear, but it’s clearly working really well for him, where am I going wrong?

I think Cav is picking the higher gear to avoid a gear change which isnt a good idea when the whole drive train is under huge stress as he reaches top speed .

Yes I think I’ve almost got the question wrong. Why does Cav sprint with a lower cadence than Hoy….

It’s very difficult to raise both arms in a victory salute on a fixed gear out of the saddle. That’s why.

And it begs the question… why don’t the track guys use gears?

Ot perhaps a better way of phrasing it would be.. if they had gears would they be quicker?

If Hoy has to sit down cos he’s spinning a fast cadence, if he could change to a higher gear, he’d be able to stand up and mash a bit, Cav style.

It used to be said that you couldn’t have anything on your bike that might stick in you in a crash. Gear levers brake levers and QR levers fell into that category.

Sturmey Archer made a 3 speed fixed hub but that wasn’t allowed either.

A little like comparing apples and oranges both are sprinting but very different or pretty different situations.
You can kind of answer this yourself, find a flat (quiet) piece of road put your bike in a gear you can reasonable get going from a very slow pace and leave it in that gear. Now ride from a standing start, up to a reasonable pace THEN accelerate to max, you will very soon find it hard to stand up as you begin to spin out. Sit down and you will still be able to put the power down.
Now do the same thing but riding onto the same stretch of road at a fast rate, begin to up your pace, this time allowing yourself to use the gears you will be able to get into a gear that you can still sprint standing up.

I disagree with the comment further up the thread about standing up being less efficient, well it’s true to an extent but standing up for a short period of time to sprint allows you to use your whole body, standing is less efficient for long periods of time, but for a short period of time you need to get everything out thus standing is efficient! Albeit less areo but Cav is still pretty compact when he sprints and keeps low.

If it was less efficient I kinda of think that the road boy’s might not do it!?!?! I think both do what’s best suited for their event. They are pro’s they don’t need to search the internet for answers! (I don’t at all mean that the OP’s question is not a good one, it is, it’s the replies that seem to suggest that Cav is doing it wrong that are funny!)

It’s a huge amount to do with equipment track riders need to be able to accelerate very quickly and get on top of the gear, they don’t have the luxury of gears they have to choose something that’s small enough to enable them to get up to speed but still big enough to hold the speed. Hoy’s sprint is a very different kettle of fish to Cavendish’s sprint, track sprints are from a very slow pace up to a very fast pace, where as a road sprint comes off riding 100’s of miles and being delivered to the line at a pace that’s much higher.

Not sure if I have explained that well or not!
Re would track riders be quicker with gears, hard to say, some ways yes some ways no but their sprints are so short (generally) I doubt it would make that much difference…and will never happen so a moot point really!

Thanks Cows in cars and others