Homebrew01

Discuss track cycling in general. Ask questions about tactics, rules, "why do they ..."

Start a separate thread for a specific event if you want spoilers.

cthenn

I love the sprint events. Those German boys are MASSIVE! They look like bodybuilders on bikes. Looks almost as silly as grown men on tiny BMX bikes...oops, sorry wrong thread!

Anyway, they're racing the Keirin today, and boy is that a weird race! I've seen it before, but boy is it odd. So what is the point of this race? I know it is basically a sprint, but why the whole lead-up with the motorbike? It looks like it's an attempt to have a sprint race with an even, moving start, as opposed to the match sprint in which they ride very slow until the last explosive moment. But it still seems odd to have so many laps slowly getting up to speed before the motorbike pulls off. Also, advantages/disadvantages of the start order?

Also, is there an "out of bounds" on the bottom of the track? I saw guys riding on the lighter blue line in the team sprint yesterday, so is there any line?

chasm54

Sorry, missed this.

The Kierin was invented by the Japanese. They gamble heavily on it to this day. It's a mass-start sprint. The derny bike that paces them round serves a couple of purposes. First it offers the opportunity for them to jockey for position, which makes for interesting racing. It can get pretty rough, though I think the commissaires have got a bit stricter about the physical stuff in recent years. Second, it ensures that when the riders are released they are going pretty fast, so there is no chance of it turning into a slow, tactical affir.

As for the start positions, some like to be at the front and get first run when the derny bike pulls off, others like to come from behind. The latter strategy is more popular on 333 metre tracks where the longer straight gives you more chance of overtaking after the final bend.

As far as the inside line is concerned, I may be out of date about this. My recollection is that you can't race on the blue "out of bounds" area but that riders aren't penalised if they have to wander on there in the early stages. Someone might correct me about that.

HardyWeinberg

NYT giant quads article

bitingduck

For timed events (like team sprint) there are sponges every 5 m through the turns at at the pursuit line in each straight. They're aligned at the top edge of the blue band, which is the edge of the official racing surface. If you ride on the sponges, the only penalty is that you're slowed by the sponges. If you ride below them you're dq'd (IIRC they're supposed to be 18 inches). There's no benefit to dropping below them in the straight, since you end up riding a longer distance if you do that, so there's just the one sponge on each straight. There's a few cm between the top of the blue band and the measurement line (black line) that determines the distance of the track.

For mass start events, the blue band is "out of bounds" and a safety zone. You aren't allowed to pass on it (relegation), but if you're pushed onto it you can ride there until it's safe to move back up onto the racing surface. It's generally constant banking equal to the banking in the straightaway all the way around so you don't have an abrupt slope change if you're pushed onto it in the turns. It's also where you go to dump speed in the event that you get a flat and manage to get down the banking with the bike upright- if you go straight to the apron you generally will find yourself sitting down with a butt full of splinters.

bitingduck

International Keirin is officially a non-contact sport and it's been fairly strictly enforced for quite a few years now. Head-butting will get you pulled from the race rather quickly.

As you say, starting position is personal preference and racing style. Even on 250 m tracks though, for several years the back was starting to be a preferred position-- for a few years in a row the Keirin at worlds was won by someone who was a kilo specialist taking a flyer. Bos made it famous, but I think Jamie Staff may have done it before him.

Keith99

I don't think refering to races over 2 days old can be much of a spoiler, especially since I'll refrain from mentioning the specific teams.

In the womens team sprint 2 teams were DQ'd. It seems both for the same technicalk infraction related to when the trailing rider passed the leading rider.

This sounded to me to be not unlike the passing zone for track (running version) relay races. Is that right? Can one be too early or too late.

Also does either actually give any advantage?

Thanks,

Keith

bitingduck

The "exchange zone" is defined as 15 meters to either side of the pursuit line (the red line in the center of each straight) and is analogous to the zone where the baton is passed in running races. When a rider has "drawn away" is not well defined in the UCI rules, but pulling up above the sprinters line (red line) is probably generally sufficient.

The advantage to be gained in making the exchange outside the zone would depend on your particular riders-- the rider who starts in front is quite thoroughly fried by the time they get around the track. They also might be riding a slightly smaller gear than the others in order to get the high acceleration (the other two riders start higher up track and get a little gravity help, too). Pulling off early would get the starter out of the way faster so the fresher rider who is probably using a gear more suitable for sustained high speed can take over. In the mens event, there may be some advantage (depending on the team and the riders) for the second rider to pull off early or late, depending on who's finishing and whether they want to keep that rider out of the wind longer or whether they've picked rider #2s gear for more acceleration or more sustained speed.

I'm an endurance rider, so Carleton can probably give more fine points on early vs. late. On the rare occasions that I ride a team sprint, I'm the #3 rider and on a big gear. It's not too different from a win and out where if there are real sprinters there I'd put on a monster gear and sit on the faster guys as they sprint it out, then cruise through for 3rd or 4th after the track empties out a little.

chasm54

Exactly what a rather famous kilo specialist did yesterday...

Keith99

Thanks bitingduck. I had no idea that they might be using different gearing.

Based on your answer it seems that pushing the limits on the zone is a reasonable thing, not at all unlike pushing the relay starts in swimming. It may only gain a couple of 1/10s of a second. But I'm sure track cycling races ahve come down to the 100ths. (I know it has in swimming, 4x100 last olympics).