I know this is not scientific and there are other variables but for a very rough straw poll what pressure do you actually run with PR4s on the Multistrada ?
I have just removed my PR4s and gone back to the Angel GT. Cannot fault the PR4s for wet weather grip and longevity but they are a bizarre shape for a tall touring bike as they tend to be hard to initially turn and then drop suddenly. The Pirellis are a far superior tyre for attacking roads IMHO. Interestingly the PR4s came last and by some margin in the recent MCN tyre test.
My Dealer told me 33F 38R for PR4's, I must admit get the pressures wrong and the front especially can get out of shape with wear. I do not have any trouble with PR4's for riding, or cornering, Certainly 3' & 4's were the best for quite a while for an all round tyre, but of late some of the newcomers seem to be more advanced and over taking the PR tyre
This is the issue I am having. They turn OK but then they seem to want to tighten up and have to be held out with handlebar pressure, it is most odd. This is more noticeable at low speed when the tyres are cold but it can also be felt at other times. Tyre pressure doesn't seem to have much effect on this. I am also getting some slight cupping / feathering of the trailing edge of the tread blocks but I think this is reasonably normal and more to do with my riding style. I have been using 35F and 37R but am currently at 36F/R. The rear will need to be changed after another 1000 miles or so and the front will have done 6500 miles by then, although it would definitely go longer. So I am just thinking about options, but on balance I am less inclined to go with another set of PR4s. What is your view on the Angel GT ?
Manual says 2.5 - 2.9 bar for front and rear (of course cold). Lower value for one up riding, higher value for two up riding with bags. But it also points out that in case you want to protect the rims from potholes and bumpy roads you need to add 0.2 - 0.3 bar to that (we get a lot of those here in Greece :angry: ). Hence 2.7 - 3.2 bar That's what I go by and I don't have any evidence to suggest I shouldn't. Couldn't fault my PR4s in any pressure in that range. I usually go for 2.7 bar. That's the pressure I used for riding on the track as well. Never felt uneasy.
@duke63 I forgot the obvious question ! Has this "dropping" issue gone away with the Pirelli Angel GTs ? Also have you gone for the load rating of 58 or 75 ?
Been playing with my pressures recently: 32/36psi gave vague front end feel. 36/36 a little better but understeering a little. Currently on 36/42, which is much better. Going to try 34 at the front and see how that does. All of these solo at 3-7°C ambient.
If you fit a tyre pressure monitoring system, you can check the pressures cold, warm, or stinking hot. If you don't have TPMS, that is not practical. Actually it is the pressures when hot which are important, but if you don't know them you have to settle for measuring them cold and guessing what they will be when hot. For high speed use (e.g. a trackday) dropping by 2 psi cold is recommended, otherwise pressure when hot might be too high..
Ive settled on 34/38 for solo riding as im not the biggest fella at about 12 stone ready to ride. 36/36 was ok but on more slippery roads there was enough of the falling off a cliff feeling to knock my confidence a bit.
By "falling off a cliff" do you mean this feeling that both @duke63 and I have referred to, the bike flops into the turn and you have to consciously hold it to stop it dropping in further ? Has 34/38 reduced or eliminated this effect, assuming we are referring to the same effect ? Does anyone else recognise this effect ?
I had these fitted before my Scotland trip the other week. I found them excellent, especially in the wet. We weren't hanging about but it will be interesting to see how they perform on a warm Sunday blast.
That's the one, a bit of resistance to lean then over it goes all of a sudden. Now that the roads are less slippery and I know there is grip it's easier to deal with. For me 34/38 is better than 36/36.
Yes. The effect I am referring to is more prominent on cold tyres, therefore it would suggest that increasing the pressures is the way to go, but at the back or front. The only other time I have felt something similar to this effect is on the original OEM Pirelli Scorpions when I had a slow puncture at the rear.
I think setting aside a dry day and doing some experimenting with pressures is called for but getting consistent temperature / pressure might be a challenge / take some time. But I would really like to know if this is an issue specific to PR4s, tyre pressures or the bike. Has anyone experienced this effect on other bikes / tyres ?
If it flops too quickly on its side, just ride faster. 34/36 f/r I tend to run mine, slightly higher in cold weather.
[QUOTE="johnv, post: 734077, member: 23329" Has anyone experienced this effect on other bikes / tyres ?[/QUOTE] Every racer does exactly that. Espectially of not using warmers, where some of the paddock with run 21spi while others 28, same tyre, same bike, same type of pace All tyres will behave differently at different pressures. Eg I used to run SC on my 848 on the road 31/32 where most were running 34/36 plus. 34 rear made the bike twicthy and horrible for me. In summer, I would drop the rear to 28. This is all cold out the garage btw, no warmers
