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I'm due to collect a second hand track bike, it will be my first for the velodrome and until now I have used the hire bikes available.

How can I prepare the tyres for use on the indoor, wooden track? I'm comfortable checking the bike mechanically otherwise.

Can I use the tyres fitted, on the indoor track, if it has been used outdoors? Do I need to clean and sand the tyres and does it change depending on what tracks the bike has been used on? I don't think it has been used on the road and will confirm with the seller.

I'll ask the coach at the velodrome before I ride it but want to turn up prepared as much as possible

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    Have to talk to someone at that velodrome. Different sites have different rules. If you see people carrying bikes inside from a car rather than rolling them, it's "inside tyres only" Do you know any other cyclists who ride there to ask directly ?
    – Criggie
    May 6, 2023 at 22:26
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    Not really because we're all beginners and using hire bikes. I think the tyre issue I was picking up on was that really brand new tyres where the mould-release agent is too slippery for the boards without cleaning or wearing it off. Used and scuffed tyres are grippier apparently, makes sense
    – Swifty
    Jun 29, 2023 at 20:58

1 Answer 1

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There are a few things that make a track bike suitable for use on the velodrome. First is the geometry. Since that’s quite a complex topic, there’s a spectrum of suitable geometry and this is already a track bike, let’s set that aside. Second is that it is fixed gear and has no brakes. Riders on the track are very close to each other and you don’t want anyone decelerating quickly which would cause a crash. Third the wheels must bolt on to the frame. Quick release skewers aren’t allowed because the high torque sprinting can cause the wheel to pull out of the dropouts, which should be track style drops to adjust chain tension. These three points just take a quick exam of the bike to confirm.

Fourth is something many people miss: a bike ridden on the velodrome needs to have wheels and tires capable of higher Gs than typical and they’re directed sideways.

A typical road bike only sees 1G on a regular basis with some shock loading when you hit a pothole. But on the track, especially shorter tracks, the wheels will see increased Gs in every turn. Those high forces are in an angled sideways direction instead of vertical. The sideways force wants to rip your tire off the rim. The forces fighting that are from the tire pressure forcing the tire bead against the rim wall.

For example, take a cyclist at 30 mph (not hard to do on the track) and a 166 m track length (like the Lexus Velodrome, which is on the short side). The turn radius is roughly 13 m. That results in 1.4 Gs. If the rider is at 40 mph they would experience 2.5 Gs every 4.6 seconds. It’s intense!

To enable such high acceleration turns, the turns (and even the straights) of the track are banked (50 degrees in the turns on this 166 m track). Cyclists do need lean at an angle to stay upright. However, the lean angle and timing won’t match the track perfectly, so there are still increased lateral forces. And there will be increased radial forces on the wheel as well. The radial forces could cause a pinch flats with too low of a pressure.

Thus it’s recommended to use high tire pressures on the velodrome. Track tires are specifically designed for this and are often rated for 125-175 PSI (9-11 bar). However be very careful to consider the pressure limit of your rims too. The maximum pressure you can safely run is the lower value of the limits of your tires and rims.

The tires used on the track are quite narrow to minimize rolling resistance. A super smooth surface like a wood track has no benefit from wide tires or low pressures. Those would only increase rolling resistance. Typical tire width for velodrome racing is 19-23 mm. Both tubular and clincher type tires and wheels can be used.

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    Don't track cyclists lean into turn to avoid lateral forces? I thought the curves were banked explicitly to allow steep leaning and to offer better grip because the banked surface is more perpendicular towards the combined gravity and G forces
    – ojs
    Aug 8, 2023 at 6:47
  • Are these tyres tubulars? Aug 8, 2023 at 11:09
  • @ojs yes, that does alter the angle of the forces. See updated answer above
    – Erik H
    Aug 8, 2023 at 11:57
  • @VladimirFГероямслава either tubulars or clinchers can be used
    – Erik H
    Aug 8, 2023 at 11:58

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