Cam Chain Wheels--How important is flex and softness?

[Cheburashka]

I checked Bill Silver's engine manual and he says it's important to have a soft, flexible rubber wheel for the cam tensioner. I checked mine, and while the upper wheel is rubbery, the lower wheel at the base of the cylinders is quite hard. What happens when a hardened wheel is used? Is it worthwhile to replace it while the engine is apart? Both wheels are very smooth and show no sign of wear.

[LOUD MOUSE]

Neither wheel was/is ever soft. ......lm

I checked Bill Silver's engine manual and he says it's important to have a soft, flexible rubber wheel for the cam tensioner. I checked mine, and while the upper wheel is rubbery, the lower wheel at the base of the cylinders is quite hard. What happens when a hardened wheel is used? Is it worthwhile to replace it while the engine is apart? Both wheels are very smooth and show no sign of wear.

[Cheburashka]

Good to know.

Thanks