Go to "Settings"- Look at the following options:
Browsing
Configure how you browse the forum.
Headers Only Brief listings showing the title of the thread, to whom the comment is addressed (if addressed), the numbered sequence within the thread, the date and time, and the posting user's screen name.
Message Bodies Full listings include headers and the bodies of messages.
Choose the number of threads or comments to return.
20 results per page
50
100
250
Teasers (also known as lead-ins) are short 100 word excerpts displayed on thread listings. Do you wish to see teasers?
Yes
No
Is there a way to get a 50 word teaser instead of 100?