MotoGP tire size spec, and psi range?

ipso said:

I run 17 Inch 120/70 (F) & 190/55 (.R)



I was under the impression MotoGP ran 16.5 inch rims, but the max tire/tyre circumference was about the same, so more contact rubber in a more egg-shaped design, and utilizing higher mm sidewalls.



[sub](Total SWAG. Sure sounds good though.)[/sub]



What are the actual sizes? Since they are all running the same tires, it should not be secretive. I'm looking for the FIM regulation documents that might contain such rules, but at this moment motogp.com is down – redirecting to Google.com for some reason.



And what psi do they run?



Thanks!

Click to expand...

This from the FIM rule book. Doesnt mention tire size, just wheel dimensions





Permitted wheel rim sizes are as follows:

Front

Rear

125cc

2.5" maximum width

3.5" maximum width

Moto2

3.75” x 17” only

6.00” x 17” only

MotoGP

4.0" maximum width

16.5” diameter only

6.25" maximum width

16.5” diameter only

In the MotoGP class for the seasons 2010, 2011, 2012, each manufacturer is restricted to two different widths of front wheel rim, and one width of rear wheel rim, within the maximum widths noted above. All MotoGP wheel rims must be 16.5” diameter.

Each MotoGP manufacturer must notify the Technical Director of their selected wheel sizes no later than the close of technical control at the first race of the 2010 season.

2.8.2



This is only a guess from what some racers have told me they run as far as pressure. 22-24 psi

Slick tyres (Slicks)



For each grand prix Bridgestone will select, in advance, two specifications of front and rear tyre from the following different available slick compounds:



Front slick tyre compounds: Soft, Medium, Hard, Extra Hard

Rear slick tyre compounds: Soft, Medium, Hard, Extra Hard



Front tyre size: 125/600R16.5

Rear tyre size: 190/650R16.5



Additionally, at some circuits the standard rear slick tyres will be replaced by asymmetric rear slick tyres, in which case Bridgestone will select two compounds from the following:



Rear asymmetric slick tyre compounds: Medium, Hard, Extra Hard



During a grand prix weekend, each rider receives five of each compound of rear slick tyre, but can choose the split of each compound of front slick tyres he receives, selecting either four of each compound, five of one compound and three of the other or vice versa.



In another change to last year’s regulations, riders can now make this front tyre selection during a grand prix weekend, rather than having to choose one race in advance.



Each rider is given three of each compound of front slick tyre on the day before the start of official practice. After the first practice he can then choose which compounds he would like for his final two front tyres, allowing each team and rider to select more of the compound that best suits their bike and the conditions.



Each rider must inform Bridgestone of his selection of front tyre specification no later than two hours after the end of the first practice session. If a rider does not select within this time he will automatically receive one tyre of each compound.



In the case of a rider being replaced after this tyre selection deadline, the replacement rider must use only the tyres allocated to the original rider.

ipso said:

Holy Murgatroyd povol - you gave specific numbers!



I'm new here. Is it too impertinent to ask for the source? (Read: are those numbers tied to a specific year/manufacture? Or are they current, relative to the picture in the OP?)



And I presume your extra zeros translate as tenths, so thus:



Front tyre size: 125/60 - R16.5



Rear tyre size: 190/65 - R16.5



I would have guessed the rear 205 but the heights make perfect sense.

Click to expand...

Bridgestone Motorsports page says thats what is available in 2010 for all teams



http://www.bridgestonemotorsport.co...s/Bridgestones+Guide+to+MotoGP+Tyres+2010.htm