Rear tyre - how often do you add air?

[stoney]

I've been having to add 2psi or so every week roughly - 100-200 miles max, while the front needs topping up very rarely - Is this normal? I very rarely have to do this with the GS. Is it anything to do with a 190 section tyre?

I can't see any signs of a puncture - there's a couple of nicks in the tyre but they only seem to be just below the surface.

[JoeC]

IMO it's all to do with the tyre, valve and the wheel (well, there's nothing else left is there !)

Both the tyre and valve are pourous to some extent and so 'may' lose air. How often it loses it nobody can say except for you by monitoring the pressues and getting to know your tyres. When you replace the tyres/valves then you will have to start all over again.
All this is to do with a tyre that can no cluts or blemishes in it as these may also cause air escape.

The wheel should not let air escape but having things like dents, damaged rims etc may cause issues.

In both of my bikes and car tyres I had Ultraseal put in and I still need to top my air up regularly.

Don't forget that tyre pressure guages are not accurtae - I got mine checked by my Trading Standards team and found that the guage measures 3psi under what it displays. This is a lot especially on a bike.

[nab 301]

I've been having to add 2psi or so every week roughly - 100-200 miles max, while the front needs topping up very rarely - Is this normal? I very rarely have to do this with the GS. Is it anything to do with a 190 section tyre?

I can't see any signs of a puncture - there's a couple of nicks in the tyre but they only seem to be just below the surface.

I had something like that a a few tyre changes ago . All was revealed when I removed the tyre . There was a panel pin protruding inside the tyre totally invisible from the outside.

[vienna]

I had the same with a front car tyre, lose a couple of PSI per week and when removed their was a pannel pin type nail not visable from the outsite.
Suggest not worth taking the risk for the cost of removal and re fit, which might cure the proble anyway if the leak is round the rim

[Dog Tyred]

Hmmmm...I'd be a bit suspicious as well. I check my pressures about once a month and never have to add air. Pressures stay rock solid.

Like Joe and Nab say, may be an unseen puncture or simply a badly fitted tyre. Eitherway, I would get it checked out.

[stoney]

Cheers guys. I've never had a fat wheel before (only had GSs and trail bikes) so I thought it may have been normal. Now knowing its not normal, I checked it again today and sure enough 2psi dropped just sitting in the garage for two days.

So up on the paddock stand it went, cleaned and checked the tyre and sure enough two small splinters of some kind are sitting just below the surface. So its booked in for a new rear tyre....darn it! Only got 1000 on this one. Still £100 fitted for an M1 seems good value to me.

Ta for all the advice!

[stoney]

Went to National tyres today in Barnsley. I was getting two fronts on the Z4 so got them to do the tyre for the 12S - "No need for replacement - thats just £12 for a repair ....just ride it like you did before!"

Top service - highly recommended!

[Lars1974]

have you tried a Tyre Monitoring kit?
does not prevent the leakage, but at least shows you everything you ride....
SmarTire does offer such a kit...check out their website www.smartire.com

have fun
Lars