The other day, as I was letting my mind wonder as usual, I had an interesting thought:

In Legacy, when Sam and Flynn where on the Solar Sailer he told his dad that he was doing up his Ducati, having spent 20 years in a shed under the tarp.

And yet, right at the start of the film, we clearly see Flynn ride off on it from Sam's bedroom window (presumably towards the Arcade).

So how did Sam get the bike back? :-/

Being about 7 years old he was obviously way too young to do it himself, so presumably someone else (probably the police) brought it back.
And if that's the case then that must presumably mean that they found it parked up at/near the Arcade, which then raises the question of why the police were so appallingly useless in analyzing the Arcade has a potential crime scene for his disappearance in 1989 (where, I assume they found his bike) when Sam found the hidden door within 10 minutes of arriving there?    

I always assumed it was a modern ducati - Sam's own.  HOWEVER I do not know cycles very well so if you were able to pinpoint that it was a bike from the 80s...then I have no clue, movie flaw?

It is definitely two bikes.  Sam's Duc is a 2010 Sport Classic.  Somewhere here is a thread I posted with a link to a Ducati forum, a thread by the guy whose bike they used in the film.

I'm not sure if we're ever told which bike Flynn's is.  It seems once I'd read it was a '78, though.

ETA: here are pics of it, in front of the house, and Flynn about to leave:

http://movies.homeofthenutty.com/displayimage.php?album=140&pid=150516#top_display_media

http://movies.homeofthenutty.com/displayimage.php?album=140&pid=150567#top_display_media

Oh, good.  The site with the screencaps is back.  Look on the left; it's dusty as hell, but that's his dad's bike, I assume: http://movies.homeofthenutty.com/displayimage.php?album=140&pid=150899#top_display_media

Here it is again: http://movies.homeofthenutty.com/displayimage.php?album=140&pid=150925#top_display_media

And one more: http://movies.homeofthenutty.com/displayimage.php?album=140&pid=150943#top_display_media

I'm not surprised Sam has it.  No doubt the police picked it up, and Sam's grandparents might've saved a lot of Flynn's stuff for Sam (or, in hopes that Flynn was coming back).  Isn't it mentioned somewhere that Flynn's bike was found at the arcade, but no trace of him?  Or maybe I'm misremembering.  It absolutely makes sense that that is what happened-- because Flynn went to the arcade that night and never left it.  Where else would his bike be, then, if not parked outside the arcade where he left it?

The question I always had is...why is it taking Sam so long to fix it up?  The bike legally would have become his at age 18, right?  Even if it's been sitting for 20 years, what can it possibly need?  Carbs cleaned, new tires, maybe some rust cleaned out of the gas tank.  Worst case scenario, engine rebuild or replacement.  Body should be in good shape as it's been covered by a tarp in a shed (and in CA, not somewhere like Ohio or WI where the cold would've taken a toll in things like cracking the seat, etc.).  I can't imagine anything that bike might need that would take 9+ years to fix... a few good weekends, maybe, but  hell, Sam doesn't even have a job (we assume?  Is it ever explicitly stated that he doesn't, or do we just sort of infer that somehow?), so he can spend 40+ hours a week on it if he wants to.  (ETA: plus it's filthy.  He couldn't even wipe it down before he stuck it in a corner???  *In 9 years???*)


But yes, it does bother me that the police never found the hidden door behind the Tron machine.  Nor did Alan, who I assume has also been over the place with a fine-tooth comb.

From what we see in the film, it seems that Sam figures it out from a groove on the floor left by the machine being moved.

http://movies.homeofthenutty.com/displayimage.php?album=140&pid=151038#top_display_media
Personally, this wouldn't tell me "hey this thing moves!" (I'd be more likely to think it was done when the machine was put into place or something) but maybe there is some reason he has to think so, that the police and Alan wouldn't.

I saw someone riding a Ducati, probs about 2 months ago.  Funnily I was in the car with others who knew a lot about TRON and we immediately started quoting TRON:Legacy.  It was an awesome bike and I too now want one.