Track Cycling: Velodrome Racing and Training Area - Research Question: Velodrome Design

Hi guys,

A current design project of mine is a building in DTLA (a charter school), and I am thinking about integrating a publicly accessible velodrome on the site.

I am currently doing research on velodrome design, and wanted to get a few opinions from people who ride on velodromes or any other oval-type courses.

I have never personally rode on one before, and I want to, but right now I just dont have the time for certification. Anyways, I am also involved in motorsport, and I know a bit about racing in general, but I had some questions about track cycling in specific.

1. Cornering: This question isnt really about design, just about racing strategy. First of all, would the strategy of taking a late apex through each of the 180 degree turns result in the ability to achieve a higher acceleration on the following straight? Or is it just a good idea to stick to the inside of the track on every bend and keep the widest line possible?

Also I'd like to know how much an advantage in acceleration you get from dropping from the top of the bank to the inside on each bend.

2: Track layout: Alright onto the actual design question. My site has a maxiumun horizontal area of about 120' x 160', so the track cannot really be a full size velodrome in any scale or configuration.

However, if any of you are familiar with American stock car racing tracks, a tri-oval configuration (like Talladega or Daytona) permit maximum speeds by using three corners instead of just two, making each turn shallower and faster between three individual straights. Because you change heading less degrees in each turn you can maintain a higher average speed through the course.

I posit that designing a tri-oval raceway with steep banking in the building will allow fast speeds even with the extremely small space I have to work with. This still would definitely not be like riding on a real velodrome - there would be much more intense cornering forces present, still. But I think it would still be a unique and enjoyable cycling experience, sort of a "mini-speedway" for bikes.

I wanted to get opinions about how feasible this would be and what elements are important to consider.

Gentlemen (and ladies), your opinions please.

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1. Cornering: This question isnt really about design, just about racing strategy. First of all, would the strategy of taking a late apex through each of the 180 degree turns result in the ability to achieve a higher acceleration on the following straight? Or is it just a good idea to stick to the inside of the track on every bend and keep the widest line possible?

I've seen some pursuiters take a late apex in their individual events as well as sprinters during certain events (flying 200M and match sprints). But, this is generally not possible in mass start (group) races where one may not be free to take whichever line they like.




Also I'd like to know how much an advantage in acceleration you get from dropping from the top of the bank to the inside on each bend.

LOTS.

But, it depends on the width and angle of track. Ed Rudolph Velodrome in the Chicago area is relatively shallow whereas on the other extreme, the velodrome in Moscow is wide and high. Then there are 50 degree tracks that are not as wide but steeper.

So, the short answer is, "it depends."


2: Track layout: Alright onto the actual design question. My site has a maxiumun horizontal area of about 120' x 160', so the track cannot really be a full size velodrome in any scale or configuration.

However, if any of you are familiar with American stock car racing tracks, a tri-oval configuration (like Talladega or Daytona) permit maximum speeds by using three corners instead of just two, making each turn shallower and faster between three individual straights. Because you change heading less degrees in each turn you can maintain a higher average speed through the course.

I posit that designing a tri-oval raceway with steep banking in the building will allow fast speeds even with the extremely small space I have to work with. This still would definitely not be like riding on a real velodrome - there would be much more intense cornering forces present, still. But I think it would still be a unique and enjoyable cycling experience, sort of a "mini-speedway" for bikes.

The UCI has defined what kind of track meets the specs for UCI events. Basically, a 250M indoor track.

Also, several events are run with opposing teams (1KM, 500M, Team Sprint, Team Pursuit). This would not be possible on a 3-sided track.

The UCI has defined what kind of track meets the specs for UCI events. Basically, a 250M indoor track.


That's for worlds and world cups. Six-days and many other events also fall under UCI, and I think they recently revised the minimum size down to 138 m (from 142 m), which is the length of Forest City Velodrome in London, Ontario. You can get details at http://uci.ch and look for the rulebooks.

You should also note that the turns are generally not just semi-circles. If you ride a velodrome you'll notice that the as you enter a turn, the acceleration comes on slowly. If they were simple semi-circles you'd go from feeling no acceleration to feeling the full V^2/R as soon as you hit the turn. The transitions from straights to turns are also tricky-- try riding Alpenrose, where they're a total mess (it feels like you're going to catch air going into the turns at the top) and compare to Home Depot Center (super smooth) and Forest City (necessarily quick, because the track is so short, but smooth and it feels like a well designed carnival ride).

There are 3 velodromes in SoCal (Encino, Home Depot Center, and San Diego) and you should spend at least a little time on each of them before you even start thinking about DIY. If you're serious about a short track, the people who would know a lot about them and be easy to get ahold of would be Dale Hughes (builds both high end and low end tracks all over the world) and John van de Velde (built the Vandedrome, which you could probably get the remaining pieces of for cheap if you can track them down.) Vandedrome was a portable track that could be built anywhere from 110 to 170 m long and had banking of 54 or 55 degrees. Some of the most skilled track racers I know thought it was a terror to ride.

Also, it only takes about an hour to get certified on HDC, or a couple hours on Encino. I don't know about San Diego-- I just showed up and raced, but I'd already been racing on other tracks before that.

How the track affects racing depends a lot on the race and who's there-- a full P/1/2 mass-start race is like a crit without corners. It's so fast most of the time that you really don't take advantage of the track much except to move off the front of a paceline. A bunch of masters who don't ride enough anymore will ride around the top and occasionally attack down the banking. In a madison you use the banking more on relief than racing. TTs are a completely different animal, but mostly you stick to the measurement line to take the shortest distance. A short track isn't likely to be very good for TTs anyway.

After re-reading your post, I think you have a fairly big misunderstanding about how bicycle track racing works. Time trials are about getting the highest average speed possible over a distance, which generally is done by riding at the highest possible constant speed. Accelerations cost a *lot* of energy, so TT riders generally avoid them. Mass start racing is about crossing the line first, which means either winning sprints from a pack (positioning and tactics) or getting the jump on other riders and getting and maintaining a gap (positioning and tactics followed by sticking to the measurement line at constant speed). You can use the track geometry to help get the jump, but every track is different (all three in SoCal are drastically different) and racers will adjust quickly to whatever the track characteristics are.

After re-reading your post, I think you have a fairly big misunderstanding about how bicycle track racing works. Time trials are about getting the highest average speed possible over a distance, which generally is done by riding at the highest possible constant speed. Accelerations cost a *lot* of energy, so TT riders generally avoid them. Mass start racing is about crossing the line first, which means either winning sprints from a pack (positioning and tactics) or getting the jump on other riders and getting and maintaining a gap (positioning and tactics followed by sticking to the measurement line at constant speed). You can use the track geometry to help get the jump, but every track is different (all three in SoCal are drastically different) and racers will adjust quickly to whatever the track characteristics are.I haven't ridden the HDC but I did ride the other two tracks. Completely different. You get so much less speed buildup at the Sandy Eggo track than Encino when you're dropping off the rail. I'd jacked up my back and didn't ride a bicycle for a few years. That was right when HDC first opened. :cry

For the most part, guys that are TTing stick to the blue line on the bottom of the track to get the shortest laps possible. The rest of us are riding around where we're riding around based on what's going on tactically at the time. (If that makes sense) Really no such thing as apexing a turn on a track.

HTH

M