Older bikes were designed for older tires - which all ran lower pressures than modern tires do, so it's best to run at the TIRE manufacturers recommendations.
Having said that, their recommendations are based on standard conditions - one rider at normal road speeds with minimal or no load.
When adding weight and speed - over 100kph - always wise to do a test. Check the pressure cold, then drive an hour or so and do another check.
If the pressure rises more than about 7 psi, it's too soft, (therefore flexing more and generating more heat) so add a couple of pounds as seems appropriate (depending on how much the pressure rose) when COLD and test again.
If the pressure rises only a couple of psi, it's too hard - drop the pressure. 4-5 psi is ideal rise, anywhere in the 2-7 range is fine.
Also note that most tires have a load rating at a maximum pressure allowed. e.g. My Metzeler ME88 rear is rated at 720 pounds at 49psi. That means a maximum pressure of 49 psi, and a max load of 720 pounds. Most tires are rated lower than that, so take care not to overload the tire.
For reference: 14.5 psi = one bar = one atmosphere. (I like psi because I'm used to it and it's much more exact)
------------------
Grant Johnson
Seek, and ye shall find.
------------------------
One world, Two wheels.
www.HorizonsUnlimited.com
__________________
Grant Johnson
Seek, and ye shall find.
------------------------
Inspiring, Informing and Connecting travellers since 1997!
www.HorizonsUnlimited.com
|