How often do cycling betting odds change?
Odds can change multiple times throughout the day. Especially on "value" odds, where punters may pile in on the apparent "good deal" and the betting house will re-adjust their odds accordingly. There's often an option to "accept all line changes" where you can accept all revisions to the odds, but there's an inherent risk to this, the odds may be marked down as well as marked up. Given the drastic swings the odds can take (definitely in cycling where the odds can be incredibly long) we generally recommend knowing what you're getting into and locking into the odds at the time you make the bet.
From what we've seen odds are more often rounded down than up and it's usually beneficial to be prepared to make your selection as soon as the order book opens up. If the odds are too short on certain riders you'll probably be aware of it, and won't make those bets initially (who knows they me round those odds up). If you're early to the book though you'll be able to grab those value odds before they get readjusted.
Odds change depending on the results of the riders as well. For example, MVDP odds for a win at this week's Tour of Flanders have been adjusted from 8.00 prior to Milan San Remo (MSR) to 3.40 after his impressive result at MSR. But this plays both ways. Pidcock (concussion), Ganna (performing less than his projected results), and Sagan (basically retired) have all been adjusted to longer odds for future races compared to where they were initially for major races in January.
It's also worth noting you can generally request odds on certain riders (see the link at the bottom of the rider list on your betting app) if they're not listed, but be aware you may be flagged by the betting house - and if you're too successful playing the odds for future bets they may limit the account you can bet. 🙂