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Team sprint

Can anyone answer a couple of questions?

There seeem to be quite large gaps on between the three riders (certainly compared to the pursuit team) -  how much difference are the lap 1 and 2 guys making to guy 3, where the gaps are that big?  Does the sheer speed mean the drafting effect still exists, even if the guy behind is not right on the wheel?

Do the rules mandate fixies, or is that a matter of choice?  Seems remarkable that they would gain sufficient time in the first 100m if they worked up through the gears, rather than having to turn the massive fixed gear from the standing start, to make up for the aero compromise. 

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

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CXR94Di2 | 8 years ago
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I suspect having fixed gear and no brakes is about weight and safety. The downside is slow start off the line. These are monster power riders and can push 100” gear ratios. You only need gears for hills

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vonhelmet | 8 years ago
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Fixies on the track aren't about aero, they're about not having a massive pile up every time someone at the front of the pack slows down for a fraction of a second changing gear or braking.

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rjfrussell | 8 years ago
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Simon, no, it wasn't a joke question, it was a genuine question, but (it appears) from a position of ignorance, though surely legitimate enquiry.

There are two parts to it-

- are fixies mandatory, or a matter of choice, because they are considered faster?

- if the latter, is it really the case that the faster initial acceleration that you would clearly have working through the gears is more than offset by the aero advantages of the fixie set up?

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wycombewheeler replied to rjfrussell | 8 years ago
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rjfrussell wrote:

Simon, no, it wasn't a joke question, it was a genuine question, but (it appears) from a position of ignorance, though surely legitimate enquiry.

There are two parts to it-

- are fixies mandatory, or a matter of choice, because they are considered faster?

- if the latter, is it really the case that the faster initial acceleration that you would clearly have working through the gears is more than offset by the aero advantages of the fixie set up?

Brakes are not allowed, so how do your gears work? Without brakes there can't be a freewheel or you need laps to coast to a stop. So how so you change gears without a freewheel? Suddenly caging the ratio means you must suddenly change the bike speed (impossible) or the leg speed.

Just when you are trying to turn a steady max effort.

I suspect man 1 has a lower ratio than 2 and 3 hence accelerating quicker but being caught at the end of the lap.

Also consider the sprint, the rider behind doesn't sit right on the wheel of the rider in front, so clearly the benefit of drafting does extend beyond a metre and the benefits of drafting as you approach at higher speed outweigh the additional savings of being closer.

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Simontuck replied to rjfrussell | 8 years ago
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rjfrussell wrote:

- are fixies mandatory, or a matter of choice, because they are considered faster?

- if the latter, is it really the case that the faster initial acceleration that you would clearly have working through the gears is more than offset by the aero advantages of the fixie set up?

 

Sorry, I thought it was pretty clear and obvious.

Fixed wheel bikes ARE mandatory on track, and it's nothing to do with performance advantage over gears. Track riding is quite a conundrum. The bikes are both the most simple AND the most scientifically advanced of any cycling discipline. But the reason they concentrate so much on aero and weight is partly because of that limitaton brought about by being on a fixed gear. You aren't allowed anything 'extra' in a track race. Nothing on the bars, no garmin telling you how many watts you've got left (although some events seem to allow either a computer or the elimination box on the bars). No water bottle. No QR's. No brakes. It's all about safety in an enclosed environment. Nothing to get caught up on.

If you ever get a chance to do a session on an indoor, or even an outdoor track (but the indoor has higher banking and hence more fun) do it. Massive fun. I've been slowly working my way through the induction stages at Stratford this year and I've never had so much fun and learnt so much about my limits. You never have to worry about people slamming on the brakes cos they don't have any and you can see the ones who aren't riding well and steer well clear!

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rjfrussell replied to Simontuck | 8 years ago
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Simontuck wrote:

rjfrussell wrote:

- are fixies mandatory, or a matter of choice, because they are considered faster?

- if the latter, is it really the case that the faster initial acceleration that you would clearly have working through the gears is more than offset by the aero advantages of the fixie set up?

 

Sorry, I thought it was pretty clear and obvious.

...

 

Thank you!  Clear now.   You just underestimated my lack of knowledge of track racing!

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Simontuck | 8 years ago
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Well described above. Regarding the gap,b asically as you accelerate you get into the slipstream as you hit a good speed and the slipstream effect then gives you a slingshot.

As for fixies. Was that a joke question? Can you imagine riding track with geared bikes, freewheels and brakes? It'd be chaos and the accidents would close the track. Track is the most pure kind of cycling. It's all about feel, technique, timing, skill and pure pure power.

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crazy-legs | 8 years ago
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You know in F1 where you want to overtake? Trying it from inches off the back wing of the car in front is is quite difficult. GIving yourself a run up at it from a distance with DRS open then smoothly passing it is a much more efficient use of energy.

Similar here except that the "car" in front is actually moving aside to let you overtake. Man Two is the car with DRS, going significantly faster than the Man One rider but still benefitting from a brief moment of tow from his slipstream as he contionues his acceleration.

 

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tritecommentbot | 8 years ago
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Still no clearer on the distances involved in slipstreaming and the effect at various distances.

 

 

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crazy-legs | 8 years ago
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Man One (and yes, it is called MAN, even when it's a woman...) is essentially a pacesetter which is why Philip Hindes does it as he's extremely consistent at putting out a 17 second Lap One. Man Two is the strongman of the team and will actually be accelerating harder than Man One and going faster at the end of his turn, it's the job of Man One to set the pace and timing, for Man Two to still be accelerating hard into his slipstream, running up beehind him rapidly to gain a "slingshot" into Lap Two and to keep accelerating to tow Man Three around into his final lap.

Man Three is more an endurance sprinter who can still finish off on his own at a rapid pace having been given that intial tow.

So Man Two has to leave a bit of a gap to give him something to run at. Getting that gap right is critical; if you're too clsoe you end up backing off fractionally and, even worse, potentially underrunning Man One (because you're going far faster) and that's a DQ offence to underrun beofre a certain point on the track. If you're too far back you miss the slipstream effect.

It's not just three people going flat out, there's actually a huge amount of technique in it. If you turned the team round and put Callum Skinner first, it wouldn't work.

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Wookie | 8 years ago
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Boardman and Hoy explained it last night. The gap between rider one and two needs to be a little extra so rider two can accelerate on to one as he/she finishes his circuit. The gap between two and three needs to be tight so rider three is as protected as possible.

 

Well that's how I interpreted what they said

 

 

 

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tritecommentbot | 8 years ago
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Thought this would be an easy thing to Google and find a quick study on.

 

Also, no. I am defeated.

 

Also curious, was wondering this last night, the gap between lead and other two is pretty huge. Maybe as much as two bike lengths on some sprints..

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rjfrussell | 8 years ago
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