Ok folks, I have an old (2009) cbr1000rr that has been retired from track duty since 2014. I got it to the race shop, all fresher up ready for action. Back then the bike was setup for 190/60 rears (Pirelli). I put on a fresh 200/60, adjusted the rear shock length 3mm to somewhat maintain the old geometry and I hit the track. Oh boy! I hate the 200. Feels like there is no edge grip (confidence), and it has lost all of its agility. A boat -compared to what I remember. The new crop of superbike Diablo slicks at 190/60 are recommended to be fired on a 5.5” rim. Has anyone got any experience mounting said tire on a 6” rim? Width wise it’s only 5mm less so I am not going to run out of tire. Bike barely pushes 155hp not like the current crop of 190+ so I don’t think I’ll run out of tire. I just want the old feeling back. ps. Geometry wise, it feels good. also I do prefer a soft carcass tire, so I rather stick with Pirellis Cheers
Yeah, I am aware of the current recommendation, I just don’t quite understand. Funny thing is that in 2025 Pirelli doesn’t mind the 180 fitted on a 6” but the 190 is for 5.5” rims. Attached pic of what I received from Pirelli moto Australia when I asked the same question (no answer or reason other than “recommended”) I need to chat with Pirelli direct I think.
I believe the 180 on the 6 inch rim is for older OEM spec stuff. My Ducati 999R back in the day had a 6 inch rim with 180 tire off the showroom floor. The 200/65 is better than the 200/60. Tires more “pointy” since it’s taller which in turn makes it feel more agile than the 200/60 was IMO. Also again IMO better edge grip with the profile. You need to run the 125/70 front with it to keep the geometry right
Thanks JB, I end up trying a 190/60. A nice improvement, not as much in terms of lap times (I picked a hand injury at work a week earlier), but the feeling was a lot better. I’ll be testing a stiffer (+1kg) rear spring on Easter Monday and slightly altered geometry. Next step is to try what you suggested. 125/70, 200/65. Something tells me that combo will be good at Phillip Island but not at this -short &tight track. Baby steps. (First time on the bike after an 11 year break)
Sorry to hijack the thread but when switching from the 180/60 to the 190 I understand that the tire is 3mm taller. Does that mean to keep my geometry numbers from my current setup if I were to just drop the rear 3mm would that compensate or am I going back down the road of a whole new setup
There you go, start reading , a lot of top notch information. https://forums.13x.com/index.php?threads/tire-size-shape-vs-bike-geometry.378342/
