03 50hp yamaha skipping at high rpm ?

[dixie706]

I have a 50 hp on 16 ft boat when motor goes to 4900 and up on rpm it begins to skip real bad . and when I add another person in boat it may start just after 4500. could this be a dirty carb , motor runs great below these rpm's , could it be fuel pump? or plugs etc. any help please . dont wanna replace unneeded parts

[boats.net]

Sounds like an ignition problem, need to check timing and for loss of spark at point it is missing.

[itsmeagain5789]

how would you check the timing?

[99yam40]

with a timing light