Been a while since I posted, but went for a little ride yesterday, and was only getting about 22mph. I noticed I was only turning about 3400 rpm. I used to run closer to 3600-3700, and I know my prop is starting to wear. I remember a long time ago reading about swapping the governor spring, or something about an adjustment screw.
Could someone explain how to adjust this, or what spring I need.

This is on a 35 GDSD

You must think with your balls. Since they are bigger than your brains.. LOL

Matt make sure your throttle is opening all the way, then make sure your neutral RPMS are where they need to be...Then if all that checkss out 100% correct and the problem occurs still, then pull the valve covers and look out for a flat cam lobe... Seems to be a briggs problem on the Horizontals.. BUT check the simple shit first.

Adjusting your governor spring won't help in your situation as you are not hitting the governor.

Could be many many things.. prop, motor could use a tune up (including all filters -don't forget new air filter), fuel system issue.

1st ck your oow rpm's and see if they are the same and if you are hitting the governor.

If that cks out, then you just have to start running down other things. Start with the simple (as stated already) and then work deeper as you eliminate things...