Tyre Pressures

Post your Misc Tech and Restoration Q&A's and general BMW queries here

Moderator: Moderators

User avatar
george baker
Club Member 14
Posts: 7273
Joined: Mon Aug 01, 2005 10:51 am
Country of Residence: uk
Location: Manchester,UK

Re: Tyre Pressures

Postby george baker » Sun Sep 27, 2015 11:11 am

Interesting, I hope I never NEED the information

Member 21, R100R, and an unused K75

User avatar
Rob Frankhamr
Club Member 14
Posts: 3301
Joined: Mon Jul 25, 2005 6:33 pm
Country of Residence: Scotland
Location: Kinloch Rannoch, Perthshire

Re: Tyre Pressures

Postby Rob Frankhamr » Thu Feb 22, 2018 4:05 pm

Let's start from the premise that the prosecution have to prove their case.
PC will say in his opinion the tyre was not. inflated correctly. He took a pressure reading with his tyre guage and....
The pressure reading was different to.. The BMW riders manual, Haynes manual, tyre manufacturers advise, local garage information plate.
So which is the correct one.
Well that's for them to prove. Obviously if a bike tyre was clearly under inflated you'd have a problem. If there was a nail in it and you'd been pulled up and had that pointed out you would go Special Reason.
If the arguement following an examination by a police examiner raised its head where it was being suggested that you were running at the wrong pressures, then that's a different arguement.
Remember, manufacturers 'recommend' tyre pressures, they are not set in stone.
In reply the rider (me) would say after a lot of research and riding out testing I have concluded that 36 front and 42 rear worked very well. I would back that up with my experience as a........t
So in order not to go on forever, they'd have a difficult job unless there was a real difference between what all the different info says and what the actual pressure is and that takes us back to the beginning, how accurate is their pressure guage?
I think there are two sets of circumstances here...

If we're talking about a stop/check... i.e. when a vehicle is pulled over by the police for whatever reason, the officer is unlikely to test tyre pressures unless the tyres are obviously under or over pressure. If, for whatever reason he does, he's far more likely to inform you and advise you to get it sorted than do anything else. If the under or over amount is so bad as to be dangerous (e.g. a complete flat) he may put a movement prohibition on the vehicle until the fault is rectified, but he's only going to do that if he thinks you're likely to drive it and put yourself and others in danger (which no one with a brain is going to do anyway). In any case, he isn't going to report for prosecution if the tyre is a few pounds over or under pressure.

The other scenario is in the aftermath of a aserious accident when the police have a duty to try to detect the cause. In this case, the investigating officer will (if possible) check the tyre pressure and, should it be decided that tyre inflation was a major contributory cause, there will be expert evidence to that effect (and potentially counter evidence from defence) and it will be up to a court to decide.

Robin Frankham

Frankhams retirement home for elderly Boxers.

Forum User
Posts: 638
Joined: Sun May 30, 2010 6:42 pm
Country of Residence: united kingdom

Re: Tyre Pressures

Postby goldenoldy » Mon May 21, 2018 2:26 pm

Interesting that I asked a similar question back in 2012! The one I bought then has lasted 6years before I ran over it. I guess that’s not too bad for a relatively cheap plastic tool. Mind you, I find that on both car and bike the pressures don’t drop as quickly as they used to back in the day.

User avatar
Forum User
Posts: 62
Joined: Tue Apr 18, 2017 11:13 am
Country of Residence: England
Location: Burton on Trent

Re: Tyre Pressures

Postby Graeme » Tue Jun 12, 2018 9:28 am

I use one of these: https://www.amazon.co.uk/RACE-RX0014-Ty ... B000VZ8S26

Sensibly priced for an ANSI Grade B (2% accuracy) gauge, which is more than good enough for road use. I "calibrated" mine when I got it by comparing it to a known calibrated gauge at 2 and 3 bar and it was spot on (within the limits of what you can read off the dial). The pressure relief valve allows very easy pressure setting too.


Return to “Miscellaneous & Restoration Q&A's”

Who is online

Users browsing this forum: No registered users and 1 guest