I have had several 180 or 190 tyres on my bike sofar some 190s nearly touched the chain cause of the width , all Depending of tha Brand of the tyre.
The pilot road 4gt I have is 190 50 17 however, my former tyre pr4 gt 180x55x17 did not measure 180 but only 174 and was way higher as any other tyre with same dims. The 190 I have right now is only 184 and to me feel better as the 180 . This all is because of the gt version it has a stiffer body and not widen in time and says the same shape. Has very good grip in the cold en wed and wont change shape in Hot weather .
My son has the pr 3. nice tyre on his fzs 600. but with 170 55 17 measures 174 as this is not the gt .
Some noticable differences