Cycling on snow and ice

[itdontgo]

Hi,

Yesterday I finallly tired of the trainer and went out in the -5C weather. The roads are full of compacted snow around here and to start with I was a bit concerned - I couldn't even get my shoe clipped in to the pedals as the back wheel spun up when I pushed down on the pedal!

The reason I post is because I ended up doing about 20mi and I realised it's not all that bad. I read an old post giving tips on ice cycling and I have to disagree with the common consensus. I found that it's better to go fast. Admittedly the accident you're going to have is going to be more substantial but the likelyhood is considerably reduced.

Firstly if you hit a patch of ice you wont be on it long - you're averaging the grip out much better by going fast. Going fast I couldn't spin up the rear wheel as easily as going slow where a patch of ice will get it started. When you're going fast you're going between grip and no grip too quick to fall due to the slippy bit.

Secondly, and probably most importantly, you have more control due to the fact you can effectively steer the bike to where you need to be when you're doing over 20mph. If you're crawling and the bike slides to the right you cant follow it because it would take too long physically move to correct the bike when you're going slow... so you go down.

Thirdly, the wheels are like big gyroscopes when you're going fast which resist roll. When the bottom of your wheel slides outwards it gains a little momentum in the outward direction. If you are going fast enough this part of the wheel still has this momentum when it rotates around to the top position (ie once it has rotated 180deg). So now the little bit of momentum it gained through sliding out has the effect of pushing the top of the wheel outward keeping the bike upright. This only really starts to have any effect when going over20mph.

The only trouble I hd yesterday was when I slowed to stop or drive up my road.

 

[fossyant]

Don't agree. The main thing with ice is not to make any sharp turns. Simples.

TBH most roads are fine. You've done one trip. Many of us are riding every day so that increases the odds, and early mornings late evenings when it's colder..... I've come off at speed and slowly on ice in the past - usually where the tarmac is very smooth, allowing sheets of ice to form.

It's black ice you watch out for, not the obvious stuff.

 

[snorri]

:troll: :troll: :troll: :troll: :troll: :troll: :troll:

 

[gbb]

Hehe, you're headed for a fall Itdontgo

Compacted snow isnt generally that bad, as fossy says, its black ice you've got to worry about...and speed, high or low, isnt going to stop you coming off. It happens so so fast when you hit some...i dont think anything will stop you (barring perhaps studded tyres)

TBF, i havnt tried maintaining good speed when it's icy, so i can't positively say you're wrong...but as a year round commuter, year after year, care and concentration is a better option than speed in my book.

Welcome to you Itdontgo, you've certainly entered with an 'interesting' observation. Welcome anyway

 

[GrasB]

It's true when travelling in a straight line on a flat surface at a constant velocity faster is better for balance. However the moment you need to turn or brake in any kind of aggressive manner you're up s**t creak without a paddle.

Even with studded tyres trying to ride around the bonnet of that car which just slid halfway across the road isn't for the faint hearted as the front & rear wheels momentarily lose grip when the studs run out of thick ice to dig into but there's still the thinnest film of ice on the road. In that state the faster you're going the more likely either end of the bike is to break away & which end goes it's completely random. Further more the faster you're going the less time you have to grab the back brake. Grabbing the back brake is a fairly important thing to do when sliding off the bike imo, it does 2 things;
1) tends to promote a less dangerous back end low side - hips tend to bruise more than break as they glance off the road rather than hit it square on
2) keeps you hands on the handle bars - if you put your hand out to break your fall you're likely to do SERIOUS damage to your arm & wrist, landing on the side means the impact is over a larger area so there's less chance of broken bones.

Just my observations from the circa 4000 miles worth of riding in icy conditions over the last 3 years.

 

[redflightuk]

Compacted snow isnt generally that bad,

You can't even walk safely on the untreated lanes around here. As they've become more slippery the vehicles have been trying to get some grip on the verges and now they have turned into an ice rink, which means the strip of snow between the wheel tracks has also been compacted now. It's bad enough on the trike, i certainly won't be trying to ride the mtb on them. Spiked tyres might work as i did manage to climb the 12% hill with my home made snow tyre(baler twine arround the trikes rear tyre)after two cars had tried and given up.

 

[Riverman]

I must admit I love the cold weather. Just need to wrap up warm... get a buff etc.

 

[GrasB]

[QUOTE 1274191"]
Firstly, the reason you cannot spin your wheels when going at a higher speed is because you cannot get as much power through the pedals as you can when going at a low speed. Hence why it is easier accelerating from 0-15mph but harder work going from 15-25mph (as well as wind resistance etc.).[/quote]
Almost there lee but not quite -

The reason you can't spin the wheels when you're going at a higher speed is because the higher the speed the lower the force transmitted to the road for the same power[sup]*[/sup]. If you're in a high gear then you're standing on the pedals to generate a lot of pedal pressure which in turn puts a lot of force into the rim, or you gear down & spin the wheels because a low pedal pressure produces a high force at the rim due to gearing[sup]†[/sup]. The reason why it's easier to accelerate from 0-15 than it is to accelerate from 15-25 is because there is less force at the rim to propel you forwards

* Interestingly unless I'm going up hill or into a strong headwind I can produce more power at 20mph than I can at 10mph! At a low enough cadence for the pedal pressure to be high enough to produce peak power the dead spot becomes big enough to effect the power over a full crank revolution (well 2 revolutions actually) & if the cadence is high enough for the dead spot not to effect the power there isn't enough resistance in the stroke to generate the high pedal force.

† my power meter cranks always show that on ice my road bikes rear wheel breaks traction at around 130w, that's at any speed be it 2mph or 20mph, at higher speeds I may not even have noticed it breaking traction but the cranks notice as the resistance to the pedal pressure reduces. Also though the actual pedal pressure that this happens at varies wildly depending on the road speed to cadence.

 

[Globalti]

Just leave the road bike at home and go out on a mountain bike.

Problem solved.

 

[Smokin Joe]

Just leave the road bike at home and go out on a mountain bike.

Problem solved.

Not on ice it isn't.

 

[e-rider]

:troll: alert

one post of utter nonsense

 

[Mad Doug Biker]

:troll: alert

one post of utter nonsense

itdontgo, whoever you are, hello, and what a hum dinger of a first post!

Me?? I'm cycling slowly, but then, I'm building my muscles up again so CAN'T go very quickly anyway.

 

[Norm]

Given that the OP was a well reasoned discussion offering an alternative to received wisdom with personal experiences and little, if anything, which was antagonistic, this late entry gets my vote as the most hypocritical post of the year.

:troll: :troll: :troll: :troll: :troll: :troll: :troll:

If the ice patches are small enough, then hitting them at speed may help to get you across with momentum before the tyres give up. However, IMO, if the ice is anything beyond 15 cm long, though, you'll be in trouble if you are at 20mph.

I reckon an MTB on off-road boots will be better than a roadie on snow or rutted ice but smooth ice is pretty much impassable without spikes.

 

[craigwend]

Had a go going a bit faster today, getting up to about 11 mph , actually felt easier -

though I suspect this was due to two previous rides being (1st) 12-18" of snow (2nd) mainly black ice / compact snow ice- hundreds of yards long...

today -sort of snow that had 're-frozen'
very few (well only one) vehicles about to compact it
pumped up the tyres to 60 psi from 40 (mtb)
oh & bit of luck

20 mph though your aving a larf...

 

[Smokin Joe]

Even if you do stay upright on ice you are out of control. If you have any reason to brake or change direction you will be on your arse.