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I've heard that information a bit differently from a Michelin tech. The pressure stamped on the side of the tire is the pressure at which the tire has it's best load carrying ability. Any more pressure than that does not increase the load it can carry.

It's hard to argue against going with what's stamped on the swing arm of your bike. However, my feeling on that is that is the pressure BMW engineers (and lawyers) want in the tire when the bike is fully loaded at it's max vehicle weight. If you buy in to that assumption, then does it not make sense that you'd get better performance and tire life from the tires running a slightly lower pressure if the bike is not fully at its max weight?

How many of us are wearing out out tires in the middles? Is that situation made better or worse by inflating the tire to the swing arm listed pressure vs. say, about 10% less?

My personal data for this rationale comes from having three different BMW bikes, an S1000RR, K1600GT, and the 1200GS LC. I've gotten great performance on all these bikes running pressures less than recommended by the manual or swing arm sticker. The 1600GT recommended 42/42. I ran that bike for tens of thousands of miles at 38/38. My S1000RR recommended 36 front/42 rear. The dunlop tech (and California Superbike school) recommends 31F/29R for the track and I ran 3 psi more for the street on each end. On my GS running TKC80 tires, I run them in the mid-20's off road and in the mid-30s on road.

I have the pro mode plug in mine and run it in Enduro Pro off-road. That mode turns off the tire warnings on the dash in the acknowledgement that riding off-road will typically have the tires aired down below their alarm thresholds.

My advice is to do whatever puts your mind at ease but don't sweat a few psi here and there.
While the Max tire pressure stamped is also the PSI that allows for the maximum load capacity of the tire that has nothing to do with your average bike, let's say hypothetically that the max load index of the front tire is 860 lbs and the max load for the rear is 1201 lbs (2061 lbs total) but yet the bike has a gross max weight rating (loaded all-up) of just 992 lbs, you don't need nor would you generally want to run the tires at their MAX PSI.

All of us wear out tires in the middle, I find that the road tires I use (Michelin Anakee III and Pilot Road 4's) both last longer with slightly more pressure than BMW recommends.
 

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BMW's Idea of Tire Pressure

I have gone through a mile long thread on TPM/RDC recommended tire pressures. BMW says a couple things: measure your tires cold, use the readings on computer, and pressure should be 36psi front, 42 psi rear at 68 degrees F. First you really can't set your tires cold like they say because the TPM pressures aren't available till you run it to 19mph and then they change within a few minutes. Next, I don't give a d--n what some elf engineer from the Black Forest says, I want to know the pressure in the tire under current conditions, not adjusted/corrected/or whatever to something you have to think too much about. And for you guys who want to bring up PV=nRT, don't. It's an ideal gas law, not a practical one plus the front and rear tires do not change at the same rate, different V and different n.

So what do I do? I measure at the valve before I ride. I set it to 36/42 and watch my display. Maybe I add, maybe I let some out after about half an hour of riding using the old 10% rule.
 

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I measure at the valve before I ride. I set it to 36/42 and watch my display. Maybe I add, maybe I let some out after about half an hour of riding using the old 10% rule.
Nope, measure cold before you go and leave it alone. Pressure change due to the tires warming up is embedded in the OEM recommendation to measure at 68*F/20*C (in practice, whatever the ambient temperature is). If you let out air after your tires warm up they'll be low after they cool down. They'll also flex more (because they're effectively underinflated), which will make them heat up even more, and heat is an enemy of tire life.

As far as I'm concerned TPI is an indicator, not gospel. Pick one gage you trust and use only that gage. If my gage says 36/42 and TPI says 37/40, I don't worry. If it changes more than a couple of PSI during the ride, I stop and investigate.
 

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My 2 cents, take it or leave it.

Wearing your tires out in the middle has more to do with riding in a straight line most of the time, than it does with tire pressure.

Generally, lower tire pressure causes the tire to heat up more and results in shorter tire life, but it also provides better grip.

If you want your tires to last longer, run higher Tire pressure, but you lose a bit of grip, especially when leaned over.

That’s why they run such low tire pressures at the track and why sport bike riders run lower pressure on the street, more grip. It also results in wearing the tires out quickly.

If you are charging hard through the corners or riding aggressively on really rough terrain, then you better have the correct pressure, otherwise a few PSI over or under really shouldn’t matter much.
 

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And the Tech is a tire expert?

I listen to the tire manufacturer myself. I've been using conti tires and they have a very-hard-to-navigate web page which eventually led to recommendations as to what they believe is the best pressure for their tires when mounted on my bike.

Without tire manufacturer input I'd likely listen to what BMW has to say.

What I, joe-tech, ricky-racer, or random internet expert has to say is likely meaningless drivel. There are probably a few who actually know what they are talking about, but how can you tell?
Most tire manufacturer pressure guides are either parameters or in lieu of guidance from the motorcycle manufacturers. The motorcycle manufacturer’s inflation instruction always takes precedence over a tire manufacturer,’s recommendation.i have this from both Metzler and Dunlop reps (several). BMW says 36/42, so that’s what I go by. I will add the dealer’s tech’s advice to the pile of proof of the old adage: “Opinions are like azzholes, everybody’s got one.” And I know what comes out of them!
 
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