BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

Do I go with what it says on the steering head or what it says on the tire? I asked the tire supplier and he said to use the sidewall info. I then asked at the dealer and they said to use the psi recommended by BMW,( 36psi front/ 42psi rear) The metzler me880 says 42 psi. I have been running at the sidewall psi and am experiencing some strange riding characteristics. I have 33,000mi on My 04' rr. I have just installed a new front tire,this is the third one since the bike was new. I'm on My fifth rear. I get a slight wiggle when over 70 +/-. I have tried adjusting the preload on the shocks and noticed it is better. With the wife on the back it's rock solid. So I'm going after the tire pressure next.

bransan wrote:...use the psi recommended by BMW,( 36psi front/ 42psi rear)...

I believe that's the answer.

I use 38F, 42R solo & double riding. Our combined weight is 290lbs so the pressure works OK for both.
I hope you are NOT using a mechanical pencil style tester. If so . . . Spend the $23 or so and get an LCD digital one.

I figure 36-39 in the front, and 39-42 rear is probable the optimum range. Different weights, different styles of riding, and different tires decide where you fall in that range.

Me 38 f and 40 r.

Those are the replies I was expecting. Not many of you are following the recommended BMW pressures. I am going to try it at exactly the psi on the steering head. Yes of course I have a digital and a dial gauge. I use both and make sure they read the same or very close. I have always used the sidewall recommended maximum. Maybe I was wrong.

my dealer said 35F and 39Rear. wrote it on the work order.
i mostly ride solo and i'm about 180lbs... prolly 200 with gear (helmet, jacket, boots etc)

42 at the rear seems too "hard" and squirrly for me. just going by feel here.

bransan wrote:Those are the replies I was expecting. Not many of you are following the recommended BMW pressures. I am going to try it at exactly the psi on the steering head. Yes of course I have a digital and a dial gauge. I use both and make sure they read the same or very close. I have always used the sidewall recommended maximum. Maybe I was wrong.

The sidewall pressure is the "Maximum that the tyre should be run at", not the default "daily use" pressure.

I'd suggest going with the "TYRE" manufacturer's recommended pressures. Mostly that's around 36/42 for the R1150R/Rockster.

Owner's Manual 2001-2005 All R1150xx models: Solo 32 psi Front 36 psi rear; Two-Up 38 psi Front 40 psi Rear
(conversions from Bar)

I don't know if this applies to street riding but here goes. I attended a CLASS training course at VIR a month ago. The instructors there said your tire pressure should increase about 10% when the tires are up to temp. I weight about 180 with gear and through trial and error 34F - 38R seemed to work out the best on the Z 6's.
Just my $.02

Marty

... tire pressure should increase about 10% when the tires are up to temp ...

Consider the following - working temperature for different tyres varies:

Sports-touring < Sports Road < Racing grooved < Slicks

You need to ride the nuts of the slicks to get the temperature up to working levels when the tires grip better.

Rain also takes temperatures down.

Consider when pressure should be measured - when tyres are stone cold, or after an hour down your local twisties with ambient temperature around 40 degrees centigrade.

I measure when cold - 36f 42r. Get good miles from Z6s and no funny business right down to the wear bars at these temps. Used the same temps for a trackday and they seemed fine for that too - they certainly heated up though!!

Croc

The instructors there said your tire pressure should increase about 10% when the tires are up to temp.

I have heard this from several sources and have confirmed that lower pressures than optimum cold will result in greater increases in pressure when hot. I use 36F and 42R cold (+ or - a pound or two) because I have determined that these pressures keep the % rise to 10% or less hot.

This method should allow you to figure out what is right for your bike, weight, load and tires rather than a blanket statement that pressure X is the answer.

36f and 42 r is where I'm at know. After about 100mi I'm noticing alot less wiggle, I also adjusted the rear preload to a lower setting and that helped some too. When I have the wife on the back I have to turn it up,but I left the tire pressures alone. You'd think after 33,000mi I'd know how to adjust this stuff for the optimum ride.