Chain Wear Indicator Tool

Really just need a caliper and allowable limits from the chain manufacturer. Some of them will give you a pin to pin measurement across a span. Some of them will give a deflection measurement with the chain off the bike. 

You can also grab the chain on the rear of the sprocket (assuming tension is correct) and see if there is any slop. That's a pretty surefire way to tell if it's ready for replacement. 

You're good!

I used to judge chains by taking them off, holding the ends in each hand and letting it loop out in front of me.

Knowing how much a new chain sags was my refrence point.

Interesting that chain wear “checkers” are common for push bikes, but unheard of for moto.
As the wear is often spread over 12 rear sprockets - checking and replacing the chain is the norm - at 0.5% worn!

KTM does sell this tool.

Here's my go to:

https://dirttricks.com/shop/hardware/dirt-tricks-extras/chainwearguage/…

Just use the front sprocket as your indicator. Once you lose a tooth there, it's time to change everything out.