Tyre pressures - winter/summer? -ice/leaves?

[SavageHoutkop]

In the spirit of 'new thread' day; here's a dumb question I've been pondering for a while.

I started commuting in June; I've never cycled in snow/ice, and have recently had experience with leaves (well, the first time I slipped it was cornering too fast, the next time I think it was trying to mount a kerb side-on because I misjudged the start of the footpath (shared use before anyone jumps on me!) as it was hidden underneath the leaves).

Following on from the other 'leaves' post it seems that leaves are, possibly, more difficult to ride on than ice. Can anyone confirm/deny?

Then I started thinking, well, if you're after more grip, usually the tyre pressure is decreased (mountain biking vs biking; rallying offroad vs onroad). However, it's usually due to mud or non-'hard' surfaces being ridden on rather than just a grip improvement (although, if tyre pressures are low, it's harder to pedal, presumably because of 'better grip'?).

So, is there an argument to say that it's better to run slightly lower tyre pressures in winter to give better grip on ice/leaves - or are you just doomed if you hit a patch, tyre pressure irrelevant?

If it helps, I cycle a Brompton so have little wheels, and high pressure.

 

[andrew_s]

Yes, lower pressures can help with grip.
But...
Too low and you'll get pinch punctures
Too low and the tyre will deform when cornering, giving "odd" handling.
Hard narrow tyres can cut through mud or snow to the road underneath, giving more grip than soft tyre that ride up on top of the mud/snow.

None of it makes a great deal of difference. It's best to recognise the state of the roads and slow down and take care.
If you do find yourself on a patch of ice, freewheel over, don't touch the brakes, go straight or with minimal steering, and don't upset your balance by looking round at what the person behind is doing. It is sometimes possible to ride over very slippery stuff that you'd have trouble walking on.

 

[Theseus]

The lower the pressure, the more likely to puncture.
Wet roads aid punctures by lubricating the cutting action

So, do you want higher grip and more punctures, or be a bit slippy and have less of them?

 

[StuartG]

As a new cyclist I would say don't ride on ice - or even when there is a hint of a frost. I've seen too many experienced cyclists downed and broken on black ice. One really bad experience might put you off for life.

Suffer public transport/car or whatever the alternative. It will make it so much nicer when you return to biking the road. Get a treadmill or something to keep you in shape through the worst weather. Cycling is supposed to be fun after all...

Leaves and gravel is more eyeballing the stuff before you hit rather than tyre pressures. Gravel can be very bad after a sudden hard rainfall. As the evenings get darker if you ride out of good street lighting make sure you have a really powerful headlight to show stuff up. You can get Cree LED lights (blinding) which you can attach with change from £20 @ Dealextreme.

 

[Theseus]

As a new cyclist I would say don't ride on ice - or even when there is a hint of a frost. I've seen too many experienced cyclists downed and broken on black ice. One really bad experience might put you off for life.

Suffer public transport/car or whatever the alternative. It will make it so much nicer when you return to biking the road. Get a treadmill or something to keep you in shape through the worst weather. Cycling is supposed to be fun after all...

Rubbish! just take more care on ice. No need to give up cycling for the winter, the vast majority of the roads are cleared and gritted with a few danger spots. Be aware of where they may be and ride accordingly.

 

[Davidc]

Andrew_s is right, but I agree with StuartG, and I'm not a new cyclist!

Ice is evil, snow's not much better. Loose gravel's bad all the time and sometimes can't be spotted early enough and has had me off several times, leaves not quite as bad but nasty, at least you can usually see them.

I reckon the worst, because it's nearly invisible and completely unpredictable, is oil on the road, especially after rain.

 

[StuartG]

Rubbish! just take more care on ice. No need to give up cycling for the winter, the vast majority of the roads are cleared and gritted with a few danger spots. Be aware of where they may be and ride accordingly.

Dangerous and misleading advice. By definition you cannot see black ice. You get it (well I find it) on supposedly well gritted roads in (warmish) London. I've seen broken legs as a consequence. As a rider with 50 years experience I too have come a cropper (but luckily no breaks) - perhaps because I know how to fall. Maybe that's also why I am still posting.

Giving your advice to a novice is just irresponsible IMHO.

 

[Theseus]

... and in my honest opinion telling someone to take an alternative form of transport because there may be a higher risk is scare mongering. There is an increased risk to all forms of transport in the winter due to the visibility & ice.

As for seeing black ice, granted you can't actually see it, but you can have a pretty good idea of where it is likely to form, such as dips in the road, to promt you to ease off a bit as you go over the suspect area.

 

[John the Monkey]

You're a braver man than me, Touche - ice seems like an effective way to break a wrist or an elbow to me - personally I don't chance it.

 

[StuartG]

... and in my honest opinion telling someone to take an alternative form of transport because there may be a higher risk is scare mongering. There is an increased risk to all forms of transport in the winter due to the visibility & ice.

No. Bikes (pedal & motor) are different. You only need to lose adhesion on one point and its all over, recovery is very difficult. You are on the ground and are at immediate risk because of bodily impact (certain) and following traffic (significant in urban areas).

For four wheeled vehicles you have to lose adhesion at least two points several feet apart. Recovery is easier (and probable if you have any skill). There is no personal risk unless the vehicle hits something and then you have a nice hi-tech metal defensive shield to protect you. To sustain any injury is very unlucky whereas to avoid injury on two wheels is lucky.

As for tubes/trains - main risk is freezing points which brings everything to a gentle halt. Boredom is the main danger.

So am I scaremongering or are you on another planet?

 

[bad boy]

As a new cyclist I would say don't ride on ice - or even when there is a hint of a frost. I've seen too many experienced cyclists downed and broken on black ice. One really bad experience might put you off for life.

Suffer public transport/car or whatever the alternative. It will make it so much nicer when you return to biking the road. Get a treadmill or something to keep you in shape through the worst weather. Cycling is supposed to be fun after all...

Leaves and gravel is more eyeballing the stuff before you hit rather than tyre pressures. Gravel can be very bad after a sudden hard rainfall. As the evenings get darker if you ride out of good street lighting make sure you have a really powerful headlight to show stuff up. You can get Cree LED lights (blinding) which you can attach with change from £20 @ Dealextreme.

Im not sure I agree but understand your concerns.

I consider any mode of transport other than my bike a failure on my part. ill adapt my ridding style as the weather dictates not give up !!.

And when I get home ill go out for a 5 mile run also come rain or shine.

 

[swee'pea99]

I fear neither wind nor snow, rain nor hail, earthquakes nor hurricanoes. I don't do ice.

 

[andyhunter]

120 psi does the job for me unless riding over cobbles or dodgy row i will lower accordingly, and i fear nothing go out sunshine, rain, hail, sleet or snow but in crappy conditions just take my care, mtbing has helped me for my bike handling skills from starting off in mtbing to doing both it and road and now really doing road and bit of mtbing. ice if very funny on the road bike i find, dodgy on decents and corners . concentration is essential when you get on your bike till you dismount . biggest problem is self-gratification artist drivers, to close as i had an experience leaning on a car window and bangin it till it shattered because of an idiot driver leaving me with barely an inch between kerb and car and i cycled on and they stopped. or people speed past you and the votex of wind hits your bike in all directions and wheels can want to go 1 direction while the frame leans in another.

 

[Fab Foodie]

On a regular bike (non-Brommie) you could run fatter tyres during the winter months for a bit extra grip, but it won't help much on ice or wet leaves IMHO, b ut for general wet surfaces a bit extra rubber won't hurt. I run 25's in the winter, slightly more contact, better cushioning against potholes in the dark and depending on tyre choice more inherant grip or p*ncture protection.

 

[Rohloff_Brompton_Rider]

i refer you to the great late sheldon brown....

http://www.sheldonbrown.com/brandt/ice.html

hi pressure slicks apparently are the correct way.