Correct Tire Pressure

[pyrocam]

further to this archived thread

http://www.kiwibiker.co.nz/forums/archive/index.php/t-178.html

Im not sure but are all bikes recommended to have the same tyre pressure? IE should my RGV150 be set to 37 and 42 like the thread suggests?

actually im also sneakily asking what my tire pressure _should_ be because I have forgotton. :confused:

I got on of those little pen shaped pressure checkers (an old one) and it reported 25 and 27 but I think im meant to be in the high 30's

your recommendations?

Edit* after some more searching I found this is actually not an uncommon topic.
eg
http://www.kiwibiker.co.nz/forums/showthread.php?t=1164&highlight=Tyre+Pressures
and
http://www.kiwibiker.co.nz/forums/showthread.php?t=2953&highlight=tire+pressure

But there is alot of figures in there. what is optimal? does it vary from bike to bike?

[FzerozeroT]

ride your bike and see what it feels like, if it feels sluggish to turn put in another psi, if it feels twitchy and slidy take out a psi, when you get it right you should feel the tyre when riding (after stopping of course) and it will be warm.

I used 28/32 in my old KR which had the same sized tyres, but then it also depends on which tyres they are. It's not a black art just practice.

[vifferman]

Im not sure but are all bikes recommended to have the same tyre pressure? IE should my RGV150 be set to 37 and 42 like the thread suggests?

actually im also sneakily asking what my tire pressure _should_ be because I have forgotton. .....
But there is alot of figures in there. what is optimal? does it vary from bike to bike?
You should run your bike tyres (initially, at least) at the pressure recommended for your model and load (it varies from one make/model to the next), then you can lower it a little to see if it feels better/worse. Note that the tyres will crack and wear faster at lower pressure, be more prone to puncturing or other damage, and that - contrary to popular biker lore - they could well have less grip in the wet, due to the stipes (tread) being closed up by tyre deformation.

I think some sports bike riders like to run lower pressures to prove that they're racer material and staunch, or summat, but road tyres are designed for repeated frequent heat cycles, a variety of road surfaces and conditions, and (generally) for a longish life, so all you are doing by running the tyres at lower pressures is wearing them out faster and making them squirm more, which can make it hard to feel what's going on.

EDIT: I've had a look, and I dunno what your tyre pressures should be. Is there not a sticker on the chain guard or somewhere that says? If you get really stuck, phone the Suzuki dealers.

[pyrocam]

ride your bike and see what it feels like, if it feels sluggish to turn put in another psi, if it feels twitchy and slidy take out a psi, when you get it right you should feel the tyre when riding (after stopping of course) and it will be warm.

I used 28/32 in my old KR which had the same sized tyres, but then it also depends on which tyres they are. It's not a black art just practice.

I dont think im experienced enough to notice much of what my tire is doing. Ill try 28/32 and see how it feels.

I always thought it was the same as a push bike and it should be as high as the tire would manage and it would ride really well, Its been a bit less powerfull of late and I suspect its the pressure.

hoping it wont be wet this arvo so I can play around with what youve said and test it out.

cheers

[Two Smoker]

I dont think im experienced enough to notice much of what my tire is doing. Ill try 28/32 and see how it feels.

I always thought it was the same as a push bike and it should be as high as the tire would manage and it would ride really well, Its been a bit less powerfull of late and I suspect its the pressure.

hoping it wont be wet this arvo so I can play around with what youve said and test it out.

cheers

I use similar pressues to F00T but 28 in the front and 30 in the rear....

[TygerTung]

Well in my cage, the higher the pressure, the better it handles, to a degree.

I have 185/60/14 at the front, and run about 38 psi cold, and 205/60/14 on the back and run about 36 cold, handles like it's on rails.

[bugjuice]

no point posting what my bike runs at, cos the back tyre alone is a few times thicker than yours, but I have noticed quite a big jump (which I already knew about) when testing the pressure at cold and hot temps. Don't think it'd really be something huge to worry about, especially with thinner tyres, but something to think about in the future.

Also, I've been told a few times that those pen gauges aren't really all that.. I tend to prefer checking the tyres at a gas station with a digital airline, but I've been told they aren't all that accurate either!! If they aren't, what is?!?!

Anyhoo, if really in doubt, ring a reputable tyre shop near by and ask them for their advice, then run down the gas station and do about that. If it feels a bit twitchy etc, then let a little out and just run on it for a bit til you get used to it..

I pulled up along one guy that must have been running about 10psi in the front of a thou! I thought he had a flat, so immidiately pointed it out, he just nodded and said that's how he runs it. Reckons he has more feel and grip. Don't think so mate.. The side walls were knackered too, from running low pressure. Give it one wet run and slip, and it'd be all over..

[Skunk]

Gas station gauges are designed for cars... Not good enough for bikes.
The gauge should be as accurate as the divisions on it ie if it's marked every 2psi it *should* be right to within 2psi...

I use a digital pen type pressure gauge. Accurate to 0.5psi. But I check that against other gauges I have. :done:

[bugjuice]

Gas station gauges are designed for cars... Not good enough for bikes.
The gauge should be as accurate as the divisions on it ie if it's marked every 2psi it *should* be right to within 2psi...

I use a digital pen type pressure gauge. Accurate to 0.5psi. But I check that against other gauges I have. :done:
A lot of bikes and cars run similar pressures, so what's the difference between a car and a bike then? eg, my car runs at around 35 all round, so does my back tyre, well, may be a little more (can't remember :confused: )

What's the tollerance on the gas station machines, and unless you're racing, is it worth worrying heaps about the difference?

[Skunk]

What's the tollerance on the gas station machines, and unless you're racing, is it worth worrying heaps about the difference?I recently found 8psi difference... Don't know if they are supposed to be THAT far out!
A few (2-3psi) can make a big difference to the feel - especially with some tyres.

[scumdog]

( Uplifts white coat from hall, straightens all four pens in pocket protector -again - smear glasses with old rag oa bit to look important and clears throat) Being a bit fussy (anal some would say) I write the tyre pressure that works best for me on the tyre by the valve using a twink pen, also try and use the same tyre hose each time I check the tyres and do it before they warm up.

Better 2lb too much pressure than the other way around.

[flyin]

Well in my cage, the higher the pressure, the better it handles, to a degree.

I have 185/60/14 at the front, and run about 38 psi cold, and 205/60/14 on the back and run about 36 cold, handles like it's on rails.

how far out does that put your speedo?
sounds like too much air to me?? i run 30-32 all round on my cage i race on 14's
handling in a car has a whole lot more factors than high tyre pressure posslibly best duscussed in a CAR forum.

[Lou Girardin]

Get a good gauge (Accugauge or the Dick Smith digital units). They're not cheap, but cheap is as cheap does.
Check your pressures weekly when stone cold.
Start with the factory recommendations. Take the bike for a 50 km or so ride and recheck the pressures. The increase should be 3 to 5 psi.

[pyrocam]

the bike doesnt have a recommended pressure as per say, It does say max (220 Lbs at 33 PSI) or something like that.

I think i understand what you mean about jittery when its too high, it seems like almost vibrating?

I might email colemans now for their recommendation

[Blakamin]

A lot of bikes and cars run similar pressures, so what's the difference between a car and a bike then? eg, my car runs at around 35 all round, so does my back tyre, well, may be a little more (can't remember :confused: )

What's the tollerance on the gas station machines, and unless you're racing, is it worth worrying heaps about the difference?
my front tyre stops the stupid a particular servo pump activating.... how acurate can their guage be?

as an ex-tyre fitter, I'll rely on my pen (1 moving part) before I'd trust a servo machine that cant even apply enuff pressure for my work van... even the guages at some tyre shops can be out by 4 psi...
and I worry about the difference coz I'm the one riding and its my life that's on the line if my tyre fails due to a pressure drop..


and the cager with 38psi... you are wearing the centre of your tread, stopping sidewall flex, increasing braking distance and generally being a danger.... :done:

[pyrocam]

Colemans response
(this is for a Suzuki RGV150)

HI THERE

25PSI FRONT
29PSI REAR

DAN

easy peasy japanesy

although it sounds a wee bit low

[MSTRS]

Maybe, but it is a very light bike which would not get a lot of sidewall flex at higher pressures.

[pyrocam]

Maybe, but it is a very light bike which would not get a lot of sidewall flex at higher pressures.

what exactly is sidewall flex, is it good or bad?
scuse my noobness

[jrandom]

25PSI FRONT
29PSI REAR

Yeah, that's what it says in the RGV and FXR manuals.

Depends on the tyres, though. When I put MT75s on my FXR, the guys at Leading Edge told me to run 36/32, and that worked real nice.

If you still have the filthy awful stock tyres on that thing (are they as bad as the FXR's?) get some real ones on pronto.

[MSTRS]

what exactly is sidewall flex, is it good or bad?
scuse my noobness
Actually, the whole tyre should flex (ever so slightly). This allows the tyre to heat up which improves grip also keeps a greater amount of tread area touching the road. Too hard - the contact area is reduced & tyre runs cool. Too soft - the tread (stipes??) close up & tyre gets too hot. You need to experiment a bit to find the best allround pressure for your bike. The bike will 'feel right'. Bear in mind tho that you are looking for a compromise that covers your riding style & dry/wet conditions. Measure tyre pressure cold. I'd say make alterations of 2psi at a time. Also, as jrandom says, the tyre make/model will be a VERY important part of performance.

[pyrocam]

If you still have the filthy awful stock tyres on that thing (are they as bad as the FXR's?) get some real ones on pronto.

Im pretty sure they are stock standard. bloddy thing, practially push bike tires.
can I actually fit those fatties I see on other bikes to mine? I assumes it would only take that one gauge of tire.

I think a bit of playing around this weekend is in order. hopefully its going to be nice weather :)