Tyre Pressures

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george baker
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Re: Tyre Pressures

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

Hi
Interesting, I hope I never NEED the information

George
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Rob Frankhamr
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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.

Rob
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goldenoldy
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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.
Brian

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Graeme
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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.
Cheers,

Graeme

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Steve Rankin
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Re: Tyre Pressures

Postby Steve Rankin » Sat Jul 17, 2021 3:21 pm

I like the fact you guys all take the checking of tire pressure seriously, I don't know about the UK but in the US, a LOT of guys wouldn't know how to check or won't check it till a failure. A very different culture here versus there.

As I said in another post, it is raining, I am bored and this is to be taken lightly, Cheers, St.

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Re: Tyre Pressures

Postby Mjolinor » Sat Jul 17, 2021 3:28 pm

Life isn't about waiting for the storm to pass, it is about learning to dance in the rain.

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george baker
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Re: Tyre Pressures

Postby george baker » Sat Jul 17, 2021 6:27 pm

Hi
I check before almost every ride if it has been a week since the last ride. Normally ok but on a 100R I often let air out trying to get the gauge on. Whoever designed the spokes needs ****ing with the wide end of a rag man's trumpet. I bet whoever designed those wheels doesn't ride them!
Member 21, R100R, and an under used K75

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Re: Tyre Pressures

Postby Mjolinor » Sat Jul 17, 2021 7:01 pm

I have just had my first lesson with Snowflakes, the R75 had spokes and they were bad enough. So far as far as I can tell you cannot inflate the tyres on Snowflakes.

Clearly I have more learning to do but I envisage it is going to have to mean opening my wallet because nothing in my box fits.

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Re: Tyre Pressures

Postby King Herald » Sun Jul 18, 2021 4:40 pm

The article basically states that they agreed a ‘blanket’ figure for convenience, not because that is the best pressure.

How can 36 and 42 be the go to figure for the tyres, regardless the size and weight of the bike, and whether there’s an 8 stone weakling riding, or 2 x 15 stone guys, with luggage? The tyre deflection and distortion they speak about in the article is a direct result of the weight on it.

With 42 in the rear tyre I get such a kick up the back end when hitting simple ridges or ruts on the road, and as I only ever ride solo I have 36 at the back, 30 at the front.
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george baker
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Re: Tyre Pressures

Postby george baker » Sun Jul 18, 2021 4:45 pm

Hi
put 36, 42 in for the ride on Friday as Continental recommend for R100R on Conti GO's, too hard I think

George
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Steve Rankin
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Re: Tyre Pressures

Postby Steve Rankin » Mon Jul 19, 2021 3:25 pm

LOL man I hate the valve position on the snowflake wheels on my 78RS and 84RT. I sometimes joke they were designed as revenge for loosing the war.

I worked at one of my first jobs installing tires both car and truck. I have owned a lot of gauges over the years cheap mechanical to expensive electronic ones.

Biggest thing is to check the air. LOL like I said earlier, maybe not a problem in the UK but here, well?

Any gauge is better than no gauge and of course the best gauge is the one that fits onto the bloody pain in the A snowflake valve stems is the best gauge.
The gauge has to pop on and not leak or you will never get an accurate reading.

I had a new guy's last tire installation come back to the shop one day because the customer thought something was wrong with the ride after having four new tires put on. Checking the air pressure found 22 in one 34 in another 24 and finally the high number 110. When I asked the new guy to check them, it was obvious he was not getting the gauge on straight and correct, so, air leaked out, he didn't get a correct reading and because the air was leaking screwed up all four tires pressure. Thankfully, he was a fast learner and I never had another problem with him.

Oh yes, I feel the pain of snowflake air checking, Cheers, St.


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