A couple of examples, the head on my 916 is set to steep and the trail is 92 mm (I think). Stock front wheel weighs 12-13 lbs (again I'm too lazy to look it up but close). My S4RS has 96 mm of trail stock and a cast snowflake wheel on the front (9-10 lbs?). I've steepened it a little, it's not twitchy at all and yet turns harder on equivalent rubber than all my other bikes. The 1198 has 96 mm of trail and a forged aluminum 7 spoke front (about 7 lbs I think) and it's pretty twitchy. So what you want for trail depends on a whole bunch of stuff. I've never measured trail on anything (that's why it took me so long to figure out the problem with the V4 SF). Ride it, tweek it and ultimately it will end up where you (not SD or Andy or Ducati) have the greatest confidence in the front end feel.
