Gidday Zeocen,
109 k's on an old ZZR 11 is bugger all to worry about, they are a trustworthy old girl, that with a bit of T.L.C & sensible servicing will see well over 200 k without to much drama
Personally I'd be looking for as later model "D" as you can possibly find for the old man to replace the 11 with, I was never overly impressed with the ZZR 12's, there a dam sight more buzzier at all revs & lack that lovely turbine like torque curve that the 11's were famous for
I.M.H.O they just lack the character that the 11's had
Ultimately it's your old mans choice aint it, just thought I'd add my five cents worth...
Another bike well worth a look would be the "A" model ZX 12 R, there way more in keeping with the old 11's character grunt wise & ya can't fault them for long distance comfort...
Food for thought if nothing else
Cheers

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