I can only get 3450rpms. Looking to get 3750 for more blade speed. The low IDLE speed is 1750. I changed the spring from OEM 3rd hole to #2hole to get this. Engine runs good, no surging etc. (onlyhas 250hrs).yes the governor is adjusted to spec
My spring #is 24-089-50s. Online somewhere i saw that #1408905 is the correct spring for 3301-3800rpms.and they mentioned different colored springs(such as purple. They said this is the way to tweak ur Hi idle speed. Anyone out there have some words of wisdom?? Josey.

The larger engines are usually set lower to 3,400 RPM's, max RPMs 3,600..
 
I don't know how to answer your specific question but your going to shorten 
the life of your engine.
 
I'd make sure the deck is clean, blades sharp, etc...  
 
Just my .02
 
 
 
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