Tyre pressures

[fredc]

2 hours ago, S-Westerly said:

Jesus. I'm not putting nitrogen in my tyres. My bike doesn't have a nice warm garage to live in so the air it gets is put in at ambient plus the slight rise in temperature due to compression.

I checked tyres yesterday and they were quite low so pumped them up to recommended pressure. Turns out gauge on pump is reading high as when I started up this morning the TPMS had a hissy fit as the pressures were way too high and I had just backed out. Got a separate gauge and both tyres were about 20% over recommended cold pressures. Adjusted them accordingly and rode 297 miles to Northumberland without any further issues. Once they warmed up they were consistent and recorded as 39 psi front (36 psi cold) and 46 psi rear (41 psi cold). 

 

air is 80% nitrogen anyway

[Gerontious]

The owners manual for my bike has nothing to say about atmospheric/ambient temperature. It gives a single recommendation for the tyres on my bike and for the way I ride. (No pillion) That is what I follow. When on tour and loaded with luggage I treat that as a pillion and increase the pressure, again as recommended by Honda. Been doing it this way for decades and it’s never given me a problem. I’m a bit old fashioned. I have this outdated idea that the people who designed, built and tested these bikes know what they’re talking about.

[curlylegend]

2 hours ago, Gerontious said:

I have this outdated idea that the people who designed, built and tested these bikes know what they’re talking about.

I agree wholeheartedly !

[S-Westerly]

10 hours ago, Gerontious said:

The owners manual for my bike has nothing to say about atmospheric/ambient temperature. It gives a single recommendation for the tyres on my bike and for the way I ride. (No pillion) That is what I follow. When on tour and loaded with luggage I treat that as a pillion and increase the pressure, again as recommended by Honda. Been doing it this way for decades and it’s never given me a problem. I’m a bit old fashioned. I have this outdated idea that the people who designed, built and tested these bikes know what they’re talking about.

My thoughts entirely and in fact that's what I've been doing for years. Purely due to the new toy having the TPMS I can see what's happening in the tyre and made me wonder if there is any affect. 

Edited January 15 by S-Westerly

[RideWithStyles]

That reason is for planes because planes go through totally different scenarios compared to bikes as they have to cope with massive temperature and pressure differentials very suddenly both internal and externally.

nitrogen is nice as an idea for bike but being more useful for racing applications than the average person and highway its overkill.

some gauges are better than others, some can under or over read at certain psi ranges as they're accuracies faulter, add a few years or so many uses and they get worse.

Well the reasons being when you check them regularly at the area you are in , youll be generally at the same or near where tou started at unless you live in or plan to go near the Himalayan mountains, then youll get bigger differences.

 

Normal air does got through changes especially you'll notice if you have had the experience of air suspension on push bikes.

 

Checked tyres on the car and bikes Saturday as i have a habit of if i do one ill check them all.

car were before xmas had dropped some but that was on a warmer day.

wifes bike was around oct/early nov had loss about 10 on both, but with skinny tyres a few pumps and its just over for storage loss.

gsf which last run was early nov, front lost about 6 and the rear one or two at most.

so alway good to check regularly.

 

Edited January 15 by RideWithStyles

[Steve_M]

13 hours ago, Gerontious said:

I’m a bit old fashioned. I have this outdated idea that the people who designed, built and tested these bikes know what they’re talking about.

When I had my VFR I tried a variety of tyres from different manufacturers. I did notice that the recommended pressures occasionally differed between tyre brands. I always went with the tyre brand recommendations - it was  a couple of PSI different as I recall, on the basis that they knew what they were doing and had carried out sufficient testing to ensure it was the best figure.

[RideWithStyles]

Really you replied with that? Post office, nhs, police, politics, teslas, microsoft etc.... they must know what they're doing right??? 

 

Ill assume your just taking it from the brouchure and test mags of the automotive industry, which is not immune to problems. it does fook up a fair bit and quite frankly most of the time its down to assumptions or some noob thats not right for the job for the decisions or has the do "rank and file".

 

short answer is Yes and no, As ball park figures and guides are great at the time of design and print (if you know what, who, why for it to be correct) but as always not always perfect...Its a safe number that is worked to but does that make it correct for everyone on anything from any era of vehicle??? No, Thats my short reply.

 

[Gerontious]

6 hours ago, Steve_M said:

When I had my VFR I tried a variety of tyres from different manufacturers. I did notice that the recommended pressures occasionally differed between tyre brands. I always went with the tyre brand recommendations - it was  a couple of PSI different as I recall, on the basis that they knew what they were doing and had carried out sufficient testing to ensure it was the best figure.

If it works for you then I’m not going to argue. But it does seem doubtful to me that the tyre makers test their tyres on individual bikes - all of them. Their recommendation will be based on a per tyre and per size basis. You might easily have two completely different bikes. That take the same size tyre but are wildly different in weight. Yet the recommended pressure is the same. Both ways seem to be a one size fits all. I do think though that the maker of my bike will know what suits it. Rather than a tyre maker who might easily have designed their tyre before my bike even existed. Pressures are really just advice - they are not rigid. “This or you’re gonna die” a few pounds either way isn’t going to hurt and if a pressure works better with your specific bike, but is a tad higher or lower then that’s not going to be a problem  There is no right or wrong. I just go with what Honda recommends. Just as I used to with BMW.

Edited January 15 by Gerontious

[Steve_M]

2 hours ago, Gerontious said:

If it works for you then I’m not going to argue. But it does seem doubtful to me that the tyre makers test their tyres on individual bikes - all of them. Their recommendation will be based on a per tyre and per size basis. You might easily have two completely different bikes. That take the same size tyre but are wildly different in weight. Yet the recommended pressure is the same. Both ways seem to be a one size fits all. I do think though that the maker of my bike will know what suits it. Rather than a tyre maker who might easily have designed their tyre before my bike even existed. Pressures are really just advice - they are not rigid. “This or you’re gonna die” a few pounds either way isn’t going to hurt and if a pressure works better with your specific bike, but is a tad higher or lower then that’s not going to be a problem  There is no right or wrong. I just go with what Honda recommends. Just as I used to with BMW.

But, on the other hand, they will know about the tyres characteristics- eg. Sidewall rigidity - and can baseline it against their other products. 

[RideWithStyles]

Air has variables but the one thing that is greater in this regard is water and it in the air all the time even in the most arid places. how much varies between towns,regions, countries, seasons let alone weather patterns....

On 15/01/2024 at 16:52, Steve_M said:

But, on the other hand, they will know about the tyres characteristics- eg. Sidewall rigidity - and can baseline it against their other products. 

Thats very vague, even if done properly. And whos to say what is better? Thats why its great we have different manufacturers and techs... i say out that i dont like bridgestones or dunlops (car or bike), are they shite? No i couldn't say that but the way they work or talk i just dont like with any vehicles i had or have.

i find Michelins carcass very soft almost to the point of not knowing what they're doing (car and bike) but id rather have the option to play with the pressure abit to tweak it, now not to say you cant with other brands but i found it easier and safer to go to from one side of soft side to hard scale from  experience...wait for the thats what she said jokes ).

 

to put it into perspective of how your one point your manual is obsolete whennyou change a certain product like tyres. This car came with bridgestones (their view of summers) out of the factory (thank goodness I wasn't ghe first owner🫨) anyway the book says 32psi, now assuming that this tyre was designed and could manage a very wide temp 10 to 40*c use case which is actually very wide use case. but with the Michelin cross climate which are brilliant with no real negatives, they are for the size and type of car listed to use as the car manufacturer says but the problem is this far too low as even the tyre is showing signs of such...even 36psi on the boarder line of this tyre and thats four tyres fairly evenly distributed with massive contact patches, what if it was the other way? Then you think what the same means for motorcycle tyres.
The soft carcass tyre from the factory with a high pressure (to get a sweet spot) from the factory but the owner puts a hard carcass tyre with the same pressure cos the tyre manufacturer got lazy or went with assumptions by saying go with owners manual, holy moly thats gonna be rough if then person likes like sort of feel??🫨.  is the tyre manufacturer or car manufacturer at fault for at least poor advice and reputation with a item that is very dynamic and has pretty much the most impact on a vehicle par the engine if your being very finicky at worst potential liability.

 

just to point out again the number(s) (were roughly 32/36 then 36/36 as my bike is but its now 36/42 for common sizes) were industry standards set (legislation) as a guide of what would be considered safe and achievable in manufacture, then design followed... how you do it needs repeatability and accountability...when in the manufacture industry you get to know how the cogs spin.

Edited January 22 by RideWithStyles

[jedibiker]

I will bet they just put some air in and didnt check it or the gauge they used isnt right. So you went over the amount needed but when you took some out it was to much. when i top mine up its suprising how a little air freeing can be 2-6 psi in a second.

if they keep going down then id go get the tyres checked for leaks.

 

I dont have the tpms and check tyres prior to every ride unless its back to back days, over 5 weeks they lose 2psi each wheel

[Mississippi Bullfrog]

I don't have TPMS - but I now have a TPMS sensor fixing device courtesy of my brother who is bit clueless and gave it to me for my birthday.

 

I suspect it's crap anyway.

 

https://www.amazon.co.uk/GERUI-Training-Pressure-Monitor-Learning/dp/B0BSC5HGZ9/ref=asc_df_B0BSC5HGZ9/?tag=googshopuk-21&linkCode=df0&hvadid=658778180565&hvpos=&hvnetw=g&hvrand=7416190432672362821&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9046503&hvtargid=pla-2212560693992&psc=1&mcid=680995b6c9d63882b6b15fc0e10978aa

 

The blurb says it should be used after every tyre rotation. That's going to make driving to the shops a bit of a faff.

[skyrider]

you will struggle touring then