As the title says, I'm just interested to see what tyre psi people or running on their multis with pr3's fitted
For the road, 36 psi front and rear cold - thus about 40 psi warm. For trackdays, 32.5 psi front and rear cold - thus about 41-42 psi hot. IMHO it's not very informative to mention a psi figure without saying whether you mean cold or hot!
Normally run 36 front & 38 rear and only check cold. If I ever take it on a trackday (unlikely with my exhaust) I'll remember your advice Pete.
When I asked Michelin, they told me 36F/42R measured when tyres are cold. That's what I use and it seems to work for my 17.5 stone bulk + E52 topbox usually with a couple of kg of stuff in it. I usually add 2psi to each tyre if I'm taking a pillion. Tyre pressures should always be set to manufacturer values and not the bike's manual/handbook ones (which are only ever meant for the OEM tyres). I've often wondered how cold is cold, since a 5 degC of temp change = a 1psi change. FWIW, I had a 2010 BMW R1200RT and in the manual cold was defined as being 20 degC ambient temp. I can accept that. Anyhow, if you do a weekly check of your tyres you'll soon spot heel and toe/cupping wear and that'll tell you if you need to use more/less air.
I agree; both the weight of the rider (+ pillion + luggage if applicable) and the cold temperature affect the figure, as you say. Ultimately it doesn't matter very much what the cold pressure is, except to the extent that it affects the hot pressure (which is what really matters).
COLD or HOT? Air or a dry Nitrogen Only? Air is mainly nitrogen (78%) and oxygen (21%). The remaining 1% is made up of argon, carbon dioxide (0.03% if outside) and other gases. Water vapour is also present in differing amounts. If the air compressor is indoors, say a busy garage instead of 300ppm the CO2 could easily be 4000ppm and the water content could be quite high. Dry OFN would be the best to fill up with for loads of reasons. Albeit a pain when adjusting unless you happen to have a bottle sitting around.
The michelin web site states F32 R35, I assume that's solo. This is PR3 but it is the same for PP3 Well done "Stuart Fordyce" post #8, everyone else is above that? I am just going to check what the garage set mine to, ride seemed a bit hard on way back.
Interesting discussion with plenty of good points raised. Thanks for that.....I do always cross reference what the bike manual says against what the tyre manufacturer recommends assuming there's info on their website - I can't have found the Moto Michelin website when I looked way back when as I found no data. Emailed Michelin yesterday.... ....and had their response this morning: All pretty clear.....stick with the 'average' pressure figures stated for ease or if you're inclined make small variations to those to account for weight.
