Winter tyre pressures.

[sidewinder]

Hello
So I have been having the usual lunch break chin wag with a fellow rider.the subject of tyre pressures came up.he recons during winter you should drop your pressures down a few psi.his reckoning is that a slightly under pressure tyre will generate more heat adding grip on the cold roads.this does sound logical to me but is there any truth here .or should I just stick to my usual pressures?..
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"Nitrous is like a cheap hooker, you want to hit it but are scared of the consequences

[barrkel]

Winter tyres have more sipes to generate heat in the surface rubber. But lowering pressure does more than just increase rolling friction, the larger surface area would be more susceptible to aquaplaning, and it would affect steering more (soft front causes the bike to want to steer into the turn, standing the bike up). And if you're doing a long motorway trip, there's a risk of overheating.

Personally I prefer to try and preserve the handling. I commute on winter tyres, and have PR3s on my VFR - both have siping, my scooter has mud & snow tyres.
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[sidewinder]

So in theory what he is saying is correct.but by what you say it will affect handling and increase aquaplaning.so I'm better of to leave them as they are..
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"Nitrous is like a cheap hooker, you want to hit it but are scared of the consequences

[Howling TerrorOutOfOffice]

I'm a saddo when it comes to tyre pressures...and suspension setup.
Always fiddling with settings, but nowt berserk. Just a psi here or a click there. They're more mental adjustments than anything, the standard settings are ok.

In short. Yes I drop the psi by 1 when it's proper cold, also dropped it by 20psi when I needed traction on mud but that's a different story.
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[sidewinder]

Might give it a go tomorrow just to cure my curiosity.then put them back to normal for the journey home
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"Nitrous is like a cheap hooker, you want to hit it but are scared of the consequences

[Nemo]

The tyres do what they're designed to do so I keep the pressures the same.

Just put on a pair of metzeler m7 rr's, brilliant tyre but that's down to construction, a lot of tyres now have high silica content, which quickens heat up time (I think) and better wet grip.
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Now own: Ducati 848 evo

[iooi]

Read this Yes i know it's state side based. But temp's are temp's no matter where you are.
Seems end of the day it makes jack shit diffidence.

Many people say to lower tyre pressure in the snow. This is wrong as increasing the area of tyre on the ground, means it has less force pressing it into the road surface. You need to increase it...
So that the tyres can bite through the snow and grip the road surface.

Notice that rally cars have really narrow tyres in snow, and wide slicks in the dry.....
They have it sussed out.
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Just because my bike was A DIVVY, does not mean i am......

[Llama-Farmer]

Changing pressures can cause tread to distort, which can defy the point of the tread.

Particularly with sipes, under inflating to get a bigger contact patch will close the sipes and reduce grip as your tyre will act more like a slick, as well as the fact that there will be a greater area, so less pressure on the ground, making aquaplaning more likely.
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[tsmith]

it does give more grip at the expense of wear and handling.

i used to drop mine by 4psi. Make sure you have plenty of tread. Don't drop them any more as the tread will start to close up making things worse.

a much better way is to fit dedicated winter tyres

[doggone]

Does anyone think getting tyres slightly warmer makes much difference when roads are wet and near freezing for weeks on end - I doubt it, especially on a ten mile commute.

[barrkel]

[Howling TerrorOutOfOffice]

The sipes mentioned on Michelin's site say they are for water dispersion.
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The Harry Turner Project

[evoboy]

I run tyres in the winter at the same pressure as I do in the summer when on the road.

Dropping 1 or 2 psi will just be a placebo effect.

One thing I have done in the past is run the compression and rebound adjusters with less damping as the oil stays very cold ( imagine the windchill on the fork legs at 50mph). Stiff damping in the wet feels terrible. Obviously no good if your bike doesn't have this adjust ability.

The only tyre I've ever had that was actually fairly warm to the touch after a 15mile trip in the pouring rain on the road is the Sava I have on the front of the NTV at the moment. The Metzeler on the rear is stone cold after the 15miles ( The Sava is run at 36psi, the Metzeler at 42psi)

Generally.
The more cuts you have in the tread, the easier it is to get heat into the tyre as the tread moves around. The downside of this is that is gives less 'feel'. The sipes will be for water dispersion and most likely to keep heat in the tyre.
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[sidewinder]

Interesting replys guys

So today I did try it.made no difference to grip but steering felt a little springy .put back to correct pressure going home and will stay that way.tyres are Michelin pilot activs.
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"Nitrous is like a cheap hooker, you want to hit it but are scared of the consequences

[Wull]

Road tyres are designed to work well over a wide temperature range,so having to adjust pressures is something you shouldn't need to worry about,so long as they're at the recommended pressure then you'll be alright.

And everything else has been covered,if it were the summer and or track riding then you'd gain from it depending on tyres being used and suspension set up.
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"Scooters are for men who want to ride motorcycles but prefer to feel the wind on their vaginas"

[sidewinder]

Don't really know what my recomended pressures are just go
Front 31psi
Rear. 33psi seems alright
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"Nitrous is like a cheap hooker, you want to hit it but are scared of the consequences

[evoboy]

[sidewinder]

I'll will give that a try evo boy . The pilot activs are a really good tyre on the divvy much much better than bt45's
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"Nitrous is like a cheap hooker, you want to hit it but are scared of the consequences

[c-m]

I ran Heidenau K60 silica tyres last winter. They were lovely and grippy in single digit temps or less.