Check the steering head for movement, This can be caused by amatuer back wheel action, Fork seals for weepage, tyre tread depth, look at service intervals, Any strange noisys, Some clutches make the strangest of noiseys (Sometimes this is normal) Sometimes bearings are on the go! Sprockets, Chain, e.t.c, e.t.c, e.t.c…
Carry out an HPI check, I do it all the time, Cant trust anyone!!!
FINALLY: If you want an R1 2006, Lava red, 6000 miles, Fsh, MINT MINT MINT, Then Pm me I can recommend someone, Who will give you a good price for your R6.
Joey 