4 stroke warmup

I usually just have it warm up while I put my boots and helmet on and that's it.

Basically until it will run with the choke off. These bikes get hot, quick.

Let it run until you can feel the radiator cap getting warm.

Choke? What's if you don't have one?!

Difficult question!
You can ask 100 people and get 101 answers.

I usually fire it up and let it run while I put on my Safety gear (Boots, Chest protector, Helmet aso)
Takes about 3-5 Minutes I guess.

Sometimes I start it and see how it behaves on the throttle and ride 1-2 slow laps.

So many ways to do it.

Honda Manual says 1 minute with cold start.

Same as the rest. 2-3 minutes or until the radiator gets warm to the touch. Doesn't take long.

Yeah, I keep forgetting I'm massively stuck in the past.

Gear up, start it... put helmet, chest pro, gloves on, idle to track.. check it out.. roll on...

This is a pet peeve of mine, I like to always let my bikes warm up till I can feel warmth on the rad cap then an easy warm up lap. Now what bugs me is the kids who pit next to me (same family every weekend, reserved pits) start up the 250f cold and rev the shit out of it right away, the thing pops and backfires like crazy. Makes me cringe.
Rant over. Move along.

I let my bike warm up until I snap the throttle and there's no bog left in the throttle.

My old baby has a bog till i can get a full radiator to spit a little fluid out. Then wahh lahh no bog.

Just a guess it may be valves.

Thats what I do, I touch the radiator next to the cap with my bare hand. When its good and "warm" ready to go, I still take it easy for a minute or two after taking off.

start and let it idle while putting on goggles then ride slowly through to pits. Typically it only takes a couple min to be at operating temp.

Read a KTM owner's manual: you'll be surprised.

Think of it this way.

The piston is only cooled with a splash or spray of oil and the fuel air mixture.

The cylinder is thick with coolant behind. Both must expand as heat build which it does in the piston very quickly.

To keep wear to a minimum letting both reach temperature is important, the tolerance between the 2 could be much closer but the manufacturer has to keep in mind the guys that fired it up and pin it. A tight tolerance would stick the piston in the bore with the "pin it cold" rider, throwing him into a flying cain16

After it's warm make sure you open the throttle up to clear it out while it's on the stand,I see a lot of 4 stroke guys do that at the practice track

what bike are you using? If its say just a day here at my personal track, ill put my helmet on, fire the bike, say a quick prayer then make a spot lap. My motors are usually trouble free