Re: what makes boat rock from side to side? .)
i'm assuming yer problem is at speed, not at rest. i hate to compare yer 31cc to my last waverunner i had. but. my waverunner did that too. mostly at medium speeds. slightly above plane. listed port, then starboard, back and forth(chine walking). the only answer i had for it was change speeds, trim different, or put it in a slight turn to keep it leaning one way. i attributed this to a deep v hull design. a pretty steep deadrise. this waverunner was great in anything but calm still waters. then the side to side crap. wondering if in slightly chopy seas, does yer 31cc still do that? as soon as the waters got some chop on them , my waverunner didn't have this issue......i never cured my problem and learned to lived with it....the waverunner was a fx140 which for pwc is considered a very stable, chop eating hull. it just didn't like the calm seas at medium speeds......sorry about compareing yer 31cc to a pwc, but thought the situation seemed similar....