Tyre pressure query

CurlyWhirly · 8 Jul 2011 at 22:38

I've recently bought these tyres.

I can't find the link now but I read an article on the Michelin website which stated the effects of having under-inflated or over-inflated motorcycle tyres.

I've been riding motorcycles for over a decade and have always allowed the front tyre to be inflated to a few PSI less than the rear tyre.

The motorcycle that I'm currently riding uses tyres that can be inflated up to 42 PSI in each tyre.

I currently put 40 PSI in the rear tyre and 35 PSI in the front tyre.

Does anyone know if it's a good idea to have this arrangement or should both tyres have roughly the same amount of air in each tyre ?

If there's any fellow bikers here who can offer advice, I'd be grateful.

Minstadave · 8 Jul 2011 at 23:35

The fronts are usually meant to be a little higher as the engine weight is over the front axel.

Draeger · 8 Jul 2011 at 23:49

Minstadave said:
The fronts are usually meant to be a little higher as the engine weight is over the front axel.

Absolutely not. The rear tyre pressure on a bike is always slightly higher than the front, with the exception of a few track bike set ups.

I run my Aprilia RSV with Michelin Pilot Power 2CT's. The Aprilia manual states 36f/42r for pressures but this is an across the board figure, an approximation if you will. Michelin recommend 34f / 36r for the 2CT's on many bikes including the RSV. They work much better at these pressures. Pilot Road 3's I'm guessing, will be similar.

Minstadave · 9 Jul 2011 at 00:02

Ooops thought he was asking about car pressures in comparison to bikes, my brain isn't working at this time!

CurlyWhirly · 9 Jul 2011 at 08:20

Minstadave said:
Ooops thought he was asking about car pressures in comparison to bikes, my brain isn't working at this time!

I think it may be my fault as I haven't posted in this section of OcUK before and this thread should be in the Biker's Cafe sub-forum I think

Anyway, I have consulted the owners manual and it says:

The recommended cold tyre pressures are:

Front tyre - 250 kPa (2,50 kgf/cm2) Rear tyre - 290 kPa (2,90 kgf/cm2)

This is what Honda recommend. This is in contrast to what is on the tyres themselves which is:

Inflate to 42 PSI

on both tyres.

p.s. on the conversion, 2,90 kgf/cm2 is the equivalent of 42 PSI and 2,50 kgf/cm2 is the equivalent of 35 PSI which is what I'm currently running them at !

This is also what my local motorcycle shop recommended.

I have always ran at these sorts of pressures (with the front tyre having slightly less air in it) but what got me wondering is that when the Honda bike manual was originally written, it was before the latest generation of motorcycle tyres came into existence and so which advice should I heed - Honda's or Michelin's ?

As a foot note, the MPR3 are the best tyres I've ever used especially in the wet and so it isn't just a gimmick about the X-sipe technology !