Toprak Razgatlioglu's journey to MotoGP has been anything but smooth. Now, he has the seat, but that is quite literally is proving to be his biggest problem. The Turkish rider's abnormally tall height for MotoGP, of 185 cm, means he has to go to extremes to make Yamaha's YZR-M1 fit him, but the knock-on effect has put him in a precarious situation regarding the usage of rear areo winglets.
The 6' 1" rider is the tallest on the grid currently, and as a result, his seat base is rather high on the Yamaha relative to the height of the rear tail unit. Due to the height of the tail unit, if Razgatlioglu were to use rear winglets, which provide added downforce to the rear tire, he'd break the bodywork parameters set by the FIM MotoGP rulebook.
Just check the main image of Razgatlioglu versus one of Alex Rins's 176 cm frame riding the same bike below.