Don't know if I'm using the correct term, I put a higher pitch prop on my outboard and sometimes when
I'm going down the lake at full throttle the motor seems to over-rev and I have to reduce the rpm's for a bit and then it
seems to work ok.

What causes this.

Cavitation but as to why that occurs I do not know the mechanics of pitch and cup on prop blades.

Catching air, I would think you could lower it a little bit and it’d help. What kind of pitch, boat and prop are you talking about?

Air around the prop. Either the prop to pad is too high causing the prop to lose grip or if its a high performance rig getting into the mid to upper 80 mph range then blow out which if you've never experienced can be quite the thrill.

Edit: over trimming can cause it as well. Not enough speed to hold the bow up, prop looses bite and slips.

answer the following for a better guess.

boat make model etc.

engine, make hp

jackplate?

if no jackplate what hole is the top bolt in on the engine bracket?

prop?

pitch?

worked?

answer those and I can probably help ya

I need to look at my boat to get those numbers.

My ZX200 did it last weekend but on the launch with the motor tucked all the way in. I've been doing some maintenance on the fuel system getting everything back in order and the power has come back to normal. I bought it as an older low hour boat, but it had a very dirty fuel system, and it didn't run all that great at first. I've been steadily adding fresh fuel every time I burn some off and a can of Sea Foam or Berryman Chem Tool plus I've changed all the filters but the ones in the VST (already bought one of them). It REALLY liked what I've done so far and you can really tell it on the hole shot. I run a 2012 200 SHO with a Yamaha Vmax 15.25 x 25 prop and it peaks @ about 5750 on the RPM's and runs anywhere from 63 to 69 mph with a slightly damaged prop. Like I said, the blow out came with the motor fully tucked in on a launch to get on plane. When it happened I thought it probably spun the hub but I've launched it a dozen or more time since then and it hasn't done it anymore. I just wondered if I needed to raise or lower the jackplate a bit?

This would be my best, uneducated guess.

first thing is to get the prop in good shape, get it to josh at steves custom props in quitman and he can make it better than new. go run it after that and see what happens.

If you do not have plugs in the prop it can also cause blow out.

+1 on too much trim. I adjusted my technique to increase trim until RPM and speed stop increasing, then decrease it just a bit for a little bit of insurance. I might lose 1-2 mph at WOT but it's better than cavitating the lower unit/prop and losing steering.