ok heres more...
look at the subframes.. if the silencers mount directly to the subframe and look crooked.. the sub frame is tweaked.. it's very common on banshees..
also look how the tank and rad cover mount up.. it there is a big gap between them and where they touch the fender.. the rad loop is probably tweaked... also pretty common on shees especially on hillclimbers.. if it flips over onto it's top sometimes they'll tweak that loop.. thats not a huge deal but it makes getting the tank out kinda of a pain sometimes.
check the top case right above the sprocket.. this will be pretty easy to tell if they have an unct stator cover.. when they loose a chain it busts the top of the case. i'll try and get ya a pic of what i mean. it doenst; effect the performance at all BUT.. might be something to mention to drop some $$ off.. make it seem like it's a bigger deal than it is.
on the front of the frame check the wide mount with the 3 holes in it.. you'll know what it is when you see it.. if it's got a funky twist the front been hit hard... if the center is kinda pushed down a bit.. they just used that to hook a tow strap too. and that would be no biggie.. but if it's got a twist.. you probably won't be able to to swap to an elka front shock... we've ran into that before.. a works will work but a elka will not..
sometimes the stock swingarms will crack on the back of the shock mount.. kinda rare but it does happen
if it's got stock a arms.. check the tops for any bending by the ball joint.. i've bent a few right there.. espeically the right side for some reason will bend that tab.. if the right wheel sits cambered in with stock a arms.. thats why.
try and rock the wheel in and out.. if so the balljoints are probably trashed.. banshees are like balsters where you cannot replace the balljoints.. you have to replace the entire arm..
the rear caliper will sometimes trash out the rubber bushing between the caliper and the mounting bracket... it's pretty common so watch for that as well..
as with any machine check the axle for striaght ness
ahh a big one.. take a gander at the footpeg bolts.. especailly if it has nerf bars and stock bolts.. (14mm head with a flange) yamahas (banshees, blasters, tri-z) all have footpeg bolt issues.. try and tighten them a bit and see if they actually tighten up.. the way the footpegs mount is there is just a 10x1.25 nut on the back of that flat piece behind the footpeg.. if that bolt is run too short it'll sometimes rip the end threads out of the nut, strip the nut, or i've seen them pop the spot weld and drop that nut completely out.. if your dealing with a hillbilly idiot.. they'll weld a bolt to the outside of the frame behind the footpeg or they will tack weld a stud into the hole... the proper way to fix that is cut the "cap" off the frame by trimming the welds.. then replacing that nut and welding it all back up.. it takes a while... other guys will fix them by drilling and tapping to a bigger size.. that works also... BUT then the footpegs need to be drilled as well.. most guys use 1/2 x 20 it seems like... that way works.. i've done that in the past as well..
check the sprocket and rear wheels hubs for play
if you pull the seat and see the front seat mount bracket looks like it's been hit down.. that no biggie.. guys do that because sometimes the front of the seat feels loose.. thats real common and no big deal..
check the intake boots. when they get old they crack.. thats any machine though..
if it's got a boost bottle plan on removing it and installing the stock crossover tube.. i've yet to see a boost bottle that doesn't leak air like crazy... they are just made wrong..
your best bet is a leakdown test.. if the guy will let you do it.. this would diagnose a bad crank seal or... another crazy leak you sometimes get.. sometimes air will make it's way between the primary gears and and crank shout and will leak between the gears... that why sometimes you see a banshee that smokes more on the right side then left.. you'd have to see how that gear is installed to understand why it can leak like that..
take a wrench across the head studs and give each one a little push... if any of them aren't tight you'll probably need a head gasket OR the headstud is in weak threads in the cylinder.
i know i'm forgetting something... i'll post when i remember it..