Tire Pressure ?

[RickS]

Ok gang, I realize this question may not have one correct answer, but here we go.

 

I ride an 04 1150RT that I purchased new. Just had a new set of Metzeler ME880Rs installed at my 18,000 mile service. They now have about 50 yards of wear (pushed out of the service department into an enclosed trailer, out of enclosed trailer back into my basement) thanks to a foot of snow still on the ground.

 

This is my third set of tires on the old RT, original set M4s, replaced at about 9,000 miles with Pilot Roads, and replaced at about 9,000 miles with the ME880s.

 

I'm lost on correct tire pressure. My BMW shop suggests 40 psi front, and 42 psi rear, under all conditions. My owners manual shows 32 f, 36 r with one person, 36 f, 39 r with two, and 36 f and 42 r with two and luggage. Metzeler web site suggests 34 f and 36 r, while both tires show 42 psi at max load.

 

Most of the my riding is one up with a few pounds in each saddle bag. I'm looking for the magic pressure for a decent ride, decent traction, and decent mileage. Help!

[Rob L]

This is a lot like an oil thread.........everyone will chime in with their own preference for lots of reasons.

FWIW I keep 40-41 in both tires. I ride a lot, but not many twisties in this part of the world. I usually get about 8000 miles out of a set of tires. I have gotten up to 12,000 when I pushed aset of tires to the limit.

[ShovelStrokeEd]

Most of this will depend on your own weight and your definitions of those very subjective parameters from your final sentence. I would put the numbers in your owner's manual at just about spot on. Your dealer is full of bovine digestive byproduct.

 

One thing that might cause me to stray a bit on the up side of the manual recommendations would be the construction of those 880's. That tire has a much stiffer (thicker) tread than the sport touring tires you previously had fitted. To avoid squirm, it might just need a couple of percentage points more tire pressure.

 

If you want to get precise about things, you could always weigh the bike using both front and rear tires. Weigh it under the conditions you expect to ride. Coupla' healthy scales and a mate to balance the bike with you and the passenger in place plus luggage. Now look at that as a percentage of the tire's maximum load capacity at max inflation pressure and adjust pressures at whatever percentage of the max inflation pressure. This is probably what BMW did when coming up with the figures in the manual.

[Paul Mihalka]

Most of this will depend on your own weight and your definitions of those very subjective parameters from your final sentence. I would put the numbers in your owner's manual at just about spot on. Your dealer is full of bovine digestive byproduct.

Sorry, Ed, but this is a rare occasion where I disagree with you. 40/42 is what I used on my R1100RT. It is a bit high, but if I'm lazy checking pressures it can go down a couple of pounds and still be in the ballpark. 38/40 I felt about ideal. When on the track I used 36/38. My estimate after a few track days was that one 150 mile track ride was equivalent to 1,500 miles on the road. On my current R1150R I use 36/40. Much lighter bike, especially on the front.

[ShovelStrokeEd]

I don't have any arguments against the 40/42 thing, just that it makes MY bikes ride like buckboards. I used to be a good deal heavier than you, Paul, and my bike still rode too harsh with that much tire pressure. I really have never been one to pay much attention to tire wear, even when I was doing 40K+ years. I tend to change them pretty early in their life cycle, preferring the feel of a tire that still retains a round profile to the hit in the wallet from frequent changes.

Current bikes are mostly kept at 36/39 regardless of load (I almost never ride 2 up and carry <40 lbs of luggage most of the time.)

[AndyT]

I've had a number of heavy bikes, including 2 sport tourers that I ran these Metzlers on and I got great mileage and good ride even 2 up at 38F 40R +or- 2 lbs. The low 30's never felt "right" to me (what ever that means)and I preferred these higher lbs. for ride and longevity.

[AndyT]

PS Welcome to the board I just realized this was your first post! I don't know what kind of bikes you've had but I love the 1150RT although a bit top heavy at stop (be carfull, I know ) You'll learn a lot about the bike and just about everything else here!

[Bob Palin]

As you can see from the previous posts there is no right answer. My experience is that it is a comfort/handling/life trade off and you are going to have to pick your point. It's been a long time since I ran my 1150 tyres as low as the manual reccomends so I won't comment on that except to say they wore out very quickly at those pressures. I now go with 38f40r in my ME880s which provides me with the balance of factors I can live with, any higher and I find the ride harsh but do gain a thousand or more miles of life. All you can do is start at one end of the scale and move up through the range seeing what you like, I would start low and increase the pressure by 2psi each time. If I'm fully loaded for a long trip I up them to 40f42r.

 

'02 R1150RT, 116,000 miles (lots of tyres), I weigh 230lbs.

[Rob L]

This is a lot like an oil thread.........everyone will chime in with their own preference for lots of reasons.

 

 

I TOLD you so

[philbytx]

+1 (must be the Fullers )

Like Killer, I run 38/40 MIN with 40/42 MAX (Deb on the back) on ME880's with no complaints .

[BFG]

Metzeler 880's

10,000+ miles

40lb front, 42lb rear

 

The front is begining to cup and the rear is a bit squared off. I'm ordering another set.

 

And welcome to the board.

[Mr. Frank]

I run 38F 40R when not fully loaded. One thing you can try is measuring the difference between cold tire pressure (say in the morning) and then warmed up pressures after a brisk 30 minute ride. Some people look for a ten percent increase while others look for 3 lbs. As a practical matter, those are pretty close. The argument is that less of an increase means the tire is not flexing enough to warm up properly (too much air), and more means it is flexing too much because the tire is too soft.

[stager]

I'm with Killer on this one too. Fully loaded I run 40/42 ....for local trips 38/40

[Burt]

Sent you a PM.