In simple terms, your maintenance schedule is based on your speed. Generally, the faster you are, the more often maintenance needs done.
Think of it as time and stress as factors in the formula.
A maintenance schedule can be formulated based on the severity of stress and the ranking of that stress.
Any load on the bike is stress. A small example of load and the severity rating follows:
Scale of 1 to 10
The bike sitting clean in a climate controlled ideal environment, prepared for storage is rated as a 1.
In contrast, a bike sitting dirty in a damp cold garage, not prepared for storage is rated at 7.
A skilled rider on a slow pace trail ride with now dust, no bumps, and keeping the engine (and all systems)at ideal temperatures, for a short period of time is about the least amount of stress a bike could be under in actual operation and still using it for its intended purpose. That would be rated at 2.
Now, opposite to that is a skilled rider on a moto track that is knarly, muddy, with some sand mixed in. All systems are being taxed to their fullest potential for a long period of time, say 35 minutes. Rating, 9
You could also look at it in terms of RPM and not just thinking about crankshaft rotation.
The more the rpm and the higher the load, the closer the parts are to fatigue failure.
After all that, my maintenance schedule is evolving as I get older and ultimately slower.
When I first stated riding again 10 years ago, I learned ( the hard way, a few times) I had to do full rebuilds before 55 hours. Crank bearings were failing around 60 hours. 3 rd and 4th gear was also failing near the same time. I was naive about the maintenance of the new fart bikes as I had not rode for 13 years prior to owning one.
The last couple years I have extended my rebuild intervals to 65 hours.
In my experience the top end is living as long as the bottom so the head gets a full rebuild at the same time as the bottom end.
This what u get when I’m riding shotgun to a basketball tourney.