Came out last summer and is to my knowledge basically the only bicycle game that's not exclusively downhill MTB.
I gave it about 3 hours and am now in world 2. It's an open world racing and exploration game, reminds me of Crash Tag Team Racing or Banjoe Kazoiie Nuts and Bolts in that way. You also get to swap out your bicycle parts with 4 stats, power, handling, grip and aero (as in aerodynamics, not air control). Some of them are grounded and understandable, but it does get wacky with it if you want and the ideal build at any given time is mostly some frankenstein monster. The devs apparently lurk on /r/xbiking and you feel the influence, but it's not reddit in a bad way.
It has a story to give some sense of progression but it's basically just plot for plots sake, allthough who cares. The bicycle people you race are all short, but well made pastiches of real life bicycle archetypes, which is fun.
The races themselves have some sort of soft categorization into mtb, gravel or road but it really doesn't matter much, There's both crits, so lap races, as well as point to point.
The cycling, to me, is sadly a bit lackluster. I mean I'm obviously on the deep end of what I'd like here but other than hills reduce your top speed way faster than they would in anything with an engine, this doesn't feel much like cycling. the handling is different from similar 4-wheeler based titles, but then you just have an accelerate and a brake button, both on a binary despite the game recommending and playing best with a controller. You start and use a singlespeed drivetrain for a good while, after around 4 hours I just unlocked my first two-speed gearbox. The singlespeed doesn't really act like a singlespeed, it's a CVT, as such the two-speed basically just feels like an optional "if you'd like some shifting" addon. Unless I crash I've not found a reason to shift out of the 2nd gear once I hit speeds because you don't slow down a lot.
It basically feels like a bit of wasted potential if you're making a bicycle videogame anyhow. Give me some 2x or 3x gearing, you don't usually find that in a racing game. Maybe instead of a mario-kart-esque drifting mechanic you gotta mind pedalstrokes so you don't pedalstrike the ground going around corners - you know, anything bicycle basically.
As it stands, if you're into bicycles or looking for a relaxing open world racing game for a few bucks this might be up your alley. Parts are abound, it's charming, the music is some really good english italopop that fits the setting and the riding is fun, just a bit too little of a bikeride.
Bonus points for being able to get off your bike and walk with it. You have to do it to interact with the world and it genuinely makes the place feel way less like you are a talking vehicle, despite that being true.
I got it when it came out and basically share your impressions. The visual design is distinct and charming and the music is pretty killer, but beyond that there's not too much happening.
If you're looking for another bike game Parcel Corps came out around the same time. It's basically the gameplay of Crazy Taxi mixed with the controls of Tony Hawk. The "bike-ness" of it is very secondary. Customizations are purely cosmetic. But the story and voice-acting are all pretty charming, and it includes some very campy video sections. It's very fun, but not particularly bike-y.