And on the street, a 180 or 190 is a smaller contact patch and thus, less rolling resistance and friction, give you slightly better gas mileage if that's any concern. Wider tires are more for lean angle. Plus you didn't say which year bike you had. The 6.0" rims are made for 190-200 tires but a 5.5 is only for a 180-190 size. Oversized tires may slip or come off the rim in hard lean pressure and also just be "floppy" in heavy turns. No need for wider tires unless you use them properly.