Tyre pressures and handling

General discussion of the BMW R1200RT/R1250RT
Post Reply
User avatar
Catfunt
Posts: 50
Joined: Tue Jun 30, 2015 8:41 pm

Tyre pressures and handling

Post by Catfunt »

I usually run 38psi front and 42psi rear on my Pilot Road 4's. This afternoon I overinflated to 43/48 as indicated by the tps. As I was only making a quick journey I couldn't be bothered to change it (I know, I know...) but the effect on handling was staggering. The bike felt like it was hinged in the middle and like I was riding on gravel. Very disconcerting indeed - just goes to show how important tyre pressures are! Lesson learned happy
---- 2013 R1200RT SE ----
User avatar
stelyn
Posts: 525
Joined: Tue Oct 21, 2014 6:17 pm

Re: Tyre pressures and handling

Post by stelyn »

Been there, done that, same  handling `feeling',  on same tyres,  now keep to 37 /42....... ;)
Only a Motorcyclist knows why a dog rides with his head out the car window
User avatar
David.
Subscriber
Posts: 7970
Joined: Fri Nov 07, 2014 7:29 pm
Location: North Yorkshire
Bike Model and Year: R1200RT (Camhead) 2012
Been liked: 328 times
Great Britain

Re: Tyre pressures and handling

Post by David. »

Does anyone know why on an LC RT, there is only one set of tyre pressures listed for all loadings on the bike, i.e. 36/42 psi.

(This was the same for a Honda VFR800 which I had in 2004).

My 2012 TC RT has two sets of tyre pressures listed, 32/36 & 36/42 psi depending on the load on the bike.

I've never understood why this is the case.
Last edited by David. on Fri Dec 18, 2015 6:54 pm, edited 1 time in total.
guest2368

Re: Tyre pressures and handling

Post by guest2368 »

I thought it was just the Metzler Z8s.  They are not as bad over inflated, but a couple of PSI under and the bike is a handful in the corners.

John
User avatar
David.
Subscriber
Posts: 7970
Joined: Fri Nov 07, 2014 7:29 pm
Location: North Yorkshire
Bike Model and Year: R1200RT (Camhead) 2012
Been liked: 328 times
Great Britain

Re: Tyre pressures and handling

Post by David. »

I've just remembered that some time ago, I sent this e-mail to BMW Customer Services:-

"The ESA has 3 load status settings, One-up, One-up with luggage and Two-up (with luggage),  are there any recommended weight guidelines for these settings?

There are two sets of tyre pressures quoted, One-up and Two-up and/or with luggage, again, are there any recommended weight guidelines for the different tyre pressures?"

Had a phone call back from BMW Customer Services, their weight guidelines are based on a rider or pillion being between 8st. and 13st., using an average of 11st.

They suggested following the guidelines set out in the handbook based on the above weights.

(At the same time, a friend had a Kawasaki GTR 1400, the factory suspension settings are for a 150 lb (10 st 10 lb) rider.)

However, this still does not answer the question why some bikes only have one set of tyre pressures for all loadings & others have two.
Last edited by David. on Sun Dec 20, 2015 11:08 am, edited 1 time in total.
guest2360

Re: Tyre pressures and handling

Post by guest2360 »

As you pointed out earlier the LC only had one set so I reckon BMW have decided changing them for a small difference in load is just not necessary.  36 42 does it all
User avatar
David.
Subscriber
Posts: 7970
Joined: Fri Nov 07, 2014 7:29 pm
Location: North Yorkshire
Bike Model and Year: R1200RT (Camhead) 2012
Been liked: 328 times
Great Britain

Re: Tyre pressures and handling

Post by David. »

It may be possible, that because the unladen weight of the LC is 24lbs greater than that of the TC & the average weight of the rider has increased over time,
which when combined together exceed the BMW weight guideline of 13st, now means that one set of tyre pressures fits all.
step2534
Posts: 112
Joined: Mon Aug 11, 2014 3:59 pm

Re: Tyre pressures and handling

Post by step2534 »

  I run at 36 psi front 42psi rear on  2011 TC.        But if Ive got the missus on I increase rear to 46 psi rear and leave the front at 36.

  Ive tried all sorts of combinations but these seem to suit me best.  If the rear is too hard ,when solo it seems to "kick/ buck" on bumps and

  uneven  surfaces.    If the front is too hard it seems to be transmitted through the steering and feels harsh/solid not comfortable at all.

  I think its a case of messing about as to what suits you and feels right.

  Im 5ft 10 and weigh 13st stripped my mate is 6ft 3 and weighs 21st so what suits  me wouldnt be right for him its like me with a passenger on all the time
User avatar
David.
Subscriber
Posts: 7970
Joined: Fri Nov 07, 2014 7:29 pm
Location: North Yorkshire
Bike Model and Year: R1200RT (Camhead) 2012
Been liked: 328 times
Great Britain

Re: Tyre pressures and handling

Post by David. »

step2534 wrote:I run at 36 psi front 42psi rear on 2011 TC. But if I've got the missus on I increase rear to 46 psi rear and leave the front at 36.
What tyres are you using, my Dunlop Roadsmarts have a Max Load rating at 42 psi on both the F & R.
step2534 wrote:I'm 5ft 10 and weigh 13st stripped my mate is 6ft 3 and weighs 21st so what suits me wouldn't be right for him its like me with a passenger on all the time.
This is exactly why I asked BMW for some weight guidelines, there are some Solo riders who weigh more than a Rider + Pillion together.
BMjoe64
Posts: 106
Joined: Mon Mar 30, 2015 5:02 pm

Re: Tyre pressures and handling

Post by BMjoe64 »

step2534 wrote:   Im 5ft 10 and weigh 13st stripped my mate is 6ft 3 and weighs 21st....

Ummm, no offence intended, just wondering what pressure you would need to have him as pillion!


;)
User avatar
richardbd
Posts: 1468
Joined: Sat Dec 13, 2014 8:40 pm
Been liked: 2 times

Re: Tyre pressures and handling

Post by richardbd »

BMjoe64 wrote:
Ummm, no offence intended, just wondering what pressure you would need to have him as pillion!


;)

Suspension upgrade required...


;) ;) ;)
step2534
Posts: 112
Joined: Mon Aug 11, 2014 3:59 pm

Re: Tyre pressures and handling

Post by step2534 »

BMjoe64  There is no way I would take him on back of me, I think at that size he would control the bike, might be wrong but it would be frightening,(for me)

                Ive no doubt when I go away to Europe fully loaded with wife and luggage , might be getting up to that sort of weight but fortunately the luggage is inanimate, doesn't think for itself and doesn't move so its not a problem  (Bit like missus really) :))
beemerboy9
Posts: 582
Joined: Sun Jan 31, 2016 9:44 am
Location: North London
Bike Model and Year: 1250RT 2019
Been liked: 16 times
Great Britain

Re: Tyre pressures and handling

Post by beemerboy9 »

DaygloDavid wrote:   because the unladen weight of the LC is 24lbs greater than that of the TC
 

Don't forget that the unladen weight of the LC is measured with panniers and the older versions are not.
John Bentall
User avatar
David.
Subscriber
Posts: 7970
Joined: Fri Nov 07, 2014 7:29 pm
Location: North Yorkshire
Bike Model and Year: R1200RT (Camhead) 2012
Been liked: 328 times
Great Britain

Re: Tyre pressures and handling

Post by David. »

beemerboy9 wrote:Don't forget that the unladen weight of the LC is measured with panniers and the older versions are not.
For both the TC & LC, the Rider's Manuals give the Unladen weight in kg, ready for the road 90% load of fuel, without OE.
Post Reply