Engine RPM

[tman7]

Can anyone tell me how to adjust the engine RPMS's on a Boxxer 421? I haven't checked yet to see what Im currently running at but my temps are down and just want to readjust if it turns out I am not running at the standard 3000 rpms when I get a hold of a tachometer.

Thanks

 

[dealtimeman]

I am pretty sure you can tune and adjust idle rpm not sure you can raise top end rpm in any way other than making sure it is running correctly.

Maybe someone more familiar with small engines can tell us how if it is possible.

 

[dgardner]

Changing max RPM on a small engine usually means adjusting the governor. This either will involve bending the linkage or turning an adjusting screw depending on engine model.

If you have the Vanguard 21 hp, this may help:

http://www.briggsandstratton.com/us/en/support/faqs/adjusting-the-governor

Hover over the image links for pictures.

 

[Able 1]

On my TM (Peak) 25 horse, all you have to do is back out the screw on the carb.. Just look at the carb when you pull out the throttle to see which screw it hits..