I am sorta new to WIS, so hopefully I can get an answer from some people that play all the time and know what they are talking about.

I have a SP that threw 240 innings in real life. I have a 4 man rotation so I only want him to pitch 6-7 innings per start. I set it so that he only throws 80 pitches per game and 90 max (which I dont think is many per start). Anyways, he always pitches thru 7 innings (easily) and I would say half the time pitches thru the 8th inning (he has done well for me on my team). When I start him, he is always between 95%-99% fatigue. My question is this, he has already thrown about 135 innings with one more start before the all star break so should I cut down number of pitches per start? If I continue to leave it at 80 pitches, will he get tired during the end the year?

Pitchers fatigue based on the number of pitches thrown per season rather than IP. So the fact that he's thrown more IP than real life doesn't matter as much as the number of pitches he has thrown. I can't describe it as well as elbirdo, so here's the link to his forum on the topic: http://www.whatifsports.com/forums/Posts.aspx?topicID=154851&page=1

Other good recent pitching threads include:
http://www.whatifsports.com/forums/Posts.aspx?topicID=452075&page=1 - good basic breakdown of pitching in the sim.
http://www.whatifsports.com/forums/Posts.aspx?TopicID=434633 - excellent breakdown of fatigue for both hitting and pitching.
http://www.whatifsports.com/forums/Posts.aspx?TopicID=457277&ThreadID=9918831#l_9918831 - great read about staff setup.

Hope it helps and happy reading.

thanks

In general most owners prefer to start their SPs at 99-100%, preferably 100%.  If he's been at 95-99% maybe you should knock his pitch counts down by 5 for a few starts and get him back to 100% and then bump them back up until he starts to tire out again.

From my experience using 240-250 RL inning pitchers n a four man rotation, you should be pretty good fatigue wise if they're set at 80/90.