Tyre pressures fully loaded

General discussion of the BMW R1200RT/R1250RT
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Northern Soul
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Tyre pressures fully loaded

Post by Northern Soul »

We're off on a big European trip next week and the bike will be fully loaded, 50L top box and both panniers. I'll also be carrying a pillion.
What do people recommend re tyre pressures? Same as the handbook or increase by a few psi, especially the rear?
Thanks
John
Vince Prince
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Re: Tyre pressures fully loaded

Post by Vince Prince »

On a recent trip to the fatherland, two up with fully loaded 49ltr box and panniers I went with the standard 36 f 42 r. Bike is 2016 RT LC. Bike felt fine at low speed and at 120 mph cruising on the Autobahn. Tyre's are Metz Z8.
Enjoy Europe it's a great place for bikes.
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Re: Tyre pressures fully loaded

Post by guest2360 »

Agreed.  2.5 and 2.9. 
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bmwdean
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Re: Tyre pressures fully loaded

Post by bmwdean »

Owner's manual puts tire pressures at 36/42 psi front/rear without reference to loading.
Jeff Dean -- http://bmwdean.com/r1200rtw.htm  -- Tucson, AZ, Madison, WI.  BMW RTs:  2015 R1200RT --  2007 R1200RT
Steve F
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Re: Tyre pressures fully loaded

Post by Steve F »

RTman10 wrote: Agreed.  2.5 and 2.9.

Yes +1
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Re: Tyre pressures fully loaded

Post by Noel »

Northern Soul wrote: We're off on a big European trip next week and the bike will be fully loaded, 50L top box and both panniers. I'll also be carrying a pillion.
What do people recommend re tyre pressures? Same as the handbook or increase by a few psi, especially the rear?
Thanks
John

I did 9,163 miles on a '16 RT w/ 70lbs of luggage, no pillion, after putting about 2K miles on new PR4GTs that came w/ my RT.  Within that 2K miles I had very prominent cupping on the front.  Both my dealer and a michelin rep recommended 40psi for the front to help retard the rate of cupping formation, so I increased to 40psi on the front and the rate of worsening of cupping seemed to slow enough for me to get full mileage out of the tires, which turned out to be nearly 12K miles.  I go 40/42 now on a new set of PR4GTs so waiting to see how much different they look after the 1st set cupped badly after such a short distance.
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Re: Tyre pressures fully loaded

Post by guest2360 »

12k is a very high mileage even for a front.  Half that is normal for most.  I think being told to increase the pressure way above the recommended was wrong. The recommendations are given for a reason.  A tyre that deforms after only 2K I would consider defective and you should have been given a replacement.
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Re: Tyre pressures fully loaded

Post by Casbar »

RTman10 wrote: 12k is a very high mileage even for a front.  Half that is normal for most.  I think being told to increase the pressure way above the recommended was wrong. The recommendations are given for a reason.  A tyre that deforms after only 2K I would consider defective and you should have been given a replacement.

I got the same recommendation from Michelin around the front tyre pressure, so am running it with more air. As I previously said, one tyre pressure for all tyres is simply stupid. Every tyre is built differently, so how can one pressure fit all. The recommended tyre pressures are recommended and are a good starting point. You can then decide on what works best within a few pounds. Logically, you can't even rely on gauges being accurate, so you may not even be on the recommended pressures, could be slightly higher or lower.
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Re: Tyre pressures fully loaded

Post by Our Gee »

RTman10 wrote: 12k is a very high mileage even for a front.  Half that is normal for most.  I think being told to increase the pressure way above the recommended was wrong. The recommendations are given for a reason.  A tyre that deforms after only 2K I would consider defective and you should have been given a replacement.
Fully agree with RTman10, I recall having a front Conti Road Attack replaced free of charge at around 3000 miles after I wasn't happy with a very uneven wear pattern. The replacement went on to around 5000 miles with normal wear.
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David.
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Re: Tyre pressures fully loaded

Post by David. »

Cupping on tyres does seem to be a function of tyre pressure v's loading on the bike, as confirmed by my tyre fitter.

The rear Dunlop RoadSmart on my RT is showing signs of cupping, will continue to use it until it's down to the legal limit.

Haven't felt any problems when riding, perhaps it is more noticeable on the front.

Asked this question before & never got an answer,
why does the TC have two sets of tyre pressures 32/36 psi & 36/42 psi depending on loading, when the LC only has 36/42 psi for all loads.

The tyre sizes & tyre manufacturer fitment recommendations are the same, including tyre pressures.
Last edited by David. on Wed Aug 24, 2016 9:17 am, edited 1 time in total.
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Re: Tyre pressures fully loaded

Post by guest2360 »

Not in my book.  Just 2.5 and 2.9 cold.
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David.
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Re: Tyre pressures fully loaded

Post by David. »

The Michelin tyre fitment guide recommends PR4 GT's for all 1200 RT's, with tyre pressures of 2.5 bar (36 psi) & 2.9 bar (42 psi).
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Re: Tyre pressures fully loaded

Post by guest2360 »

Asked this question before & never got an answer,
why does the TC have two sets of tyre pressures 32/36 psi & 36/42 psi depending on loading, when the LC only has 36/42 psi for all loads.
It doesn't. Page 68 and 163 and the back cover just quote 2.5 and 2.9 in the 2014 LC handbook.
Got it backwards David.  Could be the extra weight of the LC.
Last edited by guest2360 on Wed Aug 24, 2016 11:52 am, edited 1 time in total.
Casbar
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Re: Tyre pressures fully loaded

Post by Casbar »

DaygloDavid wrote: The Michelin tyre fitment guide recommends PR4 GT's for all 1200 RT's, with tyre pressures of 2.5 bar (36 psi) & 2.9 bar (42 psi).

If you actually phone the Michelin technical team, they will tell you something different. Like I said, you can't even guarantee pressure gages read the same, so you will be around 2.5 or 2.9 but not dead on, unless you have a gauge which is certified every x months. Garages are getting better, but home gauges read differently, I have two and they both read slightly differently. If you have ever raced, or tracked your bike, you will know, you change the tyre pressures to suit the conditions, so size does not fit all, they will be a compromise. Many have found adding a few more pounds to the front tyre reduces cupping and the contact patch is not drastically reduced. The book is a good guide though if you are not confident in trying different pressures and can't feel the difference when riding.
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Re: Tyre pressures fully loaded

Post by David. »

To gain some confidence in my tyre pressure gauges, I went to a Halfords Auto Centre, they very kindly checked a tyre pressure on my car with one of their brand new air line gauges (these are calibrated & changed every month). This checked out with a digital gauge I have. I now use a compressor with auto cut out at a pre-set (digital gauge) pressure, then cross check with the digital hand held gauge. The results are usually +/- 0.5 psi, close enough for me.
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