You're not seeing one, as there isn't one.
Is it an issue? No? Why would it be?
Try once to drive your car without looking at the rpm gauge, and see what happens. (I'll give you a hint: When the car is screaming at you, and maybe some smoke is coming out from under the hood, it's time to change gears!)
But seriously, listen to your bike, to your car, listen to what it's telling you. Is it screaming? Change to higher gear. Are you driving up a hill and you can hear the engine struggling? Change down a gear.
You'll notice all sorts of things that your vehicle is telling you, through sounds, through feelings in the stearing, in the body, how the power is responding and behaving, etc, etc.
And I can't help ponder over "I would use the tach to help me shift at correct times"
How does that work even? That's the kind of thing you'd do when you're listening to the engine.
There is no fixed law that says that you have to change gears when you're at the max rpm, or that you have to change down when you're at X rpm.
You should really start driving solely by what you're feeling, and not be fixated by the numbers.
Should follow the speed limit and such thou, ofc