Tyres for icy roads

theweeshep

Knobblies or semi-slicks best for grip?

I have found out by way of experimentation (crashing) that knobblies are crap on wet roads and semi-slicks nice and grippy, but what about icy ones? Roads, not tyres

ride_whenever

nothing grips ices except studded tyres.

I find staying loose works best and run the tyres for the ground rather than the ice. Being comfortable drifting is always helpful

.blitz

+1

ride_whenever

oh and consider the physics of any turn your trying to make, look for anything to push you round the corner, a bit of a rut, tree root etc. This will work far better than trying to lean and falling off!

theweeshep

Cheers chaps

So, knobblies or slicks I am doomed on icy roads...

Bring on the winter!!

Beardface

http://www.chainreactioncycles.com/Mode ... elID=30226

Some of those, or similar...

I'm tempted myself.. just one for the front, should be able to get the drifting sorted then, instead of washing out round every corner.. grrrr to black ice. :evil:

Northwind

It does depend on the ice, really smooth hard ice or black ice, without studs you won't grip, so you have to just be happy to slide, and try not to fall off. If it gets you unawares chances are you're going to add to your bruise collection, do try not to slide into any cars.

But, not all ice is like that, snow melt ice tends to be quite textured and wobbly, and other times there'll be snow, cracks, leaves, grit, or other stuff in the ice which makes it grippier. On this stuff, regular mtb knobblies can find enough grip to get by in my experience. Sometimes

ride_whenever

For snowy conditions, and thin surface ice a decent mud spike works pretty well as well, but there has to be something under the ice for it to go into, on the roads they're even worse!

Large volume slicks would be my advice for ice on tarmac, something like a tioga skidrow. For ice off-road, and over snow/leaves etc. then mud spikes.

theweeshep

Large volume slicks would be my advice for ice on tarmac

I'm running Schwalbe City Jets at the moment which are 2.1's so I guess it won't be too bad.

I'm happy with sliding a bit, just not on my face. I'm far too pretty

Thanks for the advice

ride_whenever

run them relatively soft as well obviously.

antfly

If you turn on ice or brake on ice you`ll be off before you know it {as I have found out on 3 occasions, black ice you don`t even know it`s there} so if the roads are really icy it`s best to just stay off them.

ride_whenever

sissy

It's good for practice, the road outside my house was very quiet, so never got gritted, me and my housemate used to go out and practice drifts and skidding... Improves your bike handling no end.

The real thing to watch out for is putting your feet down, often they'll just go from under you and you'll end up doing the splits!

antfly

Sounds like fun but it`s not much fun when you`re not expecting it and you`re approaching a junction and when you brake you find yourself sliding along the road on your back.

ride_whenever

So you adjust your riding for the conditions... I was coaching on an iced over towpath this morning, in the dark. I ended up using a smaller gear for less torque and being extra careful. The consequences of a mess up there are more likely to be fatal than a slide on the roads.

antfly

Yes but canal towpaths are flat and straight with no traffic, you can ride how you want. On the road there are hills and turns and traffic, and you can adjust your riding all you like it won`t help you if you have to brake or turn on black ice.

ride_whenever

Except it isn't. You can adjust for riding on ice, the falls happen slower at low speed, so you have more time to correct for them.

antfly

It isn`t what?
You`ll never convince me it`s possible to ride safely on ice on the road, unless you`re on a tricycle.

Northwind

antfly wrote:

If you turn on ice or brake on ice you`ll be off before you know it

No offence but that's what people say when they don't know how to do it. It's perfectly possible to turn and brake on ice, it's just a bit hard. You need to lower the speed, turn more slowly and gently (and likewise with braking), really feel for the grip... And slide, correct, just keep it together as best you can. It's all about being progressive and gentle. It's not something you want to be doing but it's also not a guaranteed crash if you know how to approach it (and have the foresight to plan for it)

The other thing as a cyclist is to pick your road position differently- we're very used to cutting corners sharper than cars can, using bits of the road nobody else does, but those bits get less tyres on them which means less heat and less wear. So, when it's safe to do so, ride in the "cart tracks" ie where the car wheels go. But more importantly, watch out for the bits where nobody else goes- ie right in the centre of T junctions, the apexes of corners... Careful when turning off one road onto another too.

ride_whenever

isn't flat or straight, anyway.

Northwind, spot on. Ironically you need to do the exact opposite in the snow. Seeking out the clean snow for the best traction.

antfly

I agree with Northwind`s second paragraph but maybe we`re thinking of different kinds of ice. :? I was really referring to a road bike, they don`t slide they just go straight over, a mountain bike might be slightly better on ice.

Northwind

Everything slides the same way, mtb, road bike, motorbike... I was almost caught out on my skinny-tyred commuter last week by not taking my own advice, cut across a bit of dead tarmac and slid the front right out. Managed to catch it fast and steer into it then restart the corner with more control, as much luck as skill that time, very close thing but only because I screwed up :roll: Hadn't really realised it was that cold. You don't get long to react though, you're spot on there but the point of all this is to say that it's more about planning.

I don't know if I'd have really bothered to work all this out for pushbike use but I've done 10 scottish winters by motorbike, you need to work out how to deal with snow and ice or you get the bus a lot. The principles are identical, it's just easier on a pushbike as you're not fighting 170 kilos or trying to put 80bhp on the ground. But pushbikes have their own traps, the agility can be a hindrance because you tend to turn too fast or overcorrect. But the principles are the same.

antfly

All I can tell you is the three times I came off on ice there was no warning and no chance at all to react, none whatsoever.

Northwind

Was it cold?

antfly

Naturally.

Northwind

Then there was a warning

This one maybe won't work for anyone else, but it's worked for me... Beside my garage door, there's an old cooking pot, which fills with rain. I've found over the years that as long as it's not frozen, I can ride pretty much normally. Once it crusts over, time to be a little careful. But if I can kick it and the ice doesn't break, then it's properly cold and time to assume every wet-looking patch is potentially dangerous. Sounds really daft but it does work

antfly

Yes I look for ice on on our flat bit of roof which holds a bit of water but the last time I came off there was no ice anywhere else but I had climbed about 200ft so it was obviously a little bit colder up there, something I didn`t consider.

Northwind

Yeah, that's exactly the opposite of what got me funnilly enough, it was baltic up at my house but my office is about 400 feet lower so I thought "It'll be fine down here" :oops:

antfly

It just goes to prove however careful you are the ice will get you in the end.

diy

Motorbikes and bicycles are not the same at all when it come to managing skids and grip. There is a vast difference between the centre of gravity, which on a motorbike is much lower. There is also the issue of controlling the power. Lastly tyre design is significantly different as most will have a greater contact patch when cornering than upright. There aren't many cycle tyres that work that way. On a motorbike you get a lot more warning because of the low CoG and the fact that the bike mass is 2-3 times that of the rider.

A cycle is unlikely to highside following a slide its more likely to low side

but the basic balance between grip, corning and acceleration is the same If you use more of one you will have less of the others.

Northwind

antfly wrote:

It just goes to prove however careful you are the ice will get you in the end.

It didn't quite get me, though, since I corrected the skid and rode it out. I'd not have lost control like that if I'd had my brain engaged but luckily my subconscious is better on a bike than I am

diy wrote:

Motorbikes and bicycles are not the same at all when it come to managing skids and grip. There is a vast difference between the centre of gravity, which on a motorbike is much lower. There is also the issue of controlling the power. Lastly tyre design is significantly different as most will have a greater contact patch when cornering than upright. There aren't many cycle tyres that work that way. On a motorbike you get a lot more warning because of the low CoG and the fact that the bike mass is 2-3 times that of the rider.

Every technique for low grip riding that works on a motorbike, works on a mountain bike and works on a road bike. You're weighing available grip vs your demands on it, which are the same. The lower centre of gravity affects how the bike reacts when skidding but it doesn't significantly affect when you skid or why you skid. The only substantial difference is how you react, since you can't muscle a motorbike as you do a pushbike.

As for tyres, it's true that motorbike tyres mostly have larger contact patches when leaned significantly over. Best of luck making use of that on ice

diy

Northwind wrote:

The lower centre of gravity affects how the bike reacts when skidding but it doesn't significantly affect when you skid or why you skid.

Sorry North, you are complete wrong the centre of gravity (front to back/top to bottom) makes a massive difference to when a tyre will slip free for both acceleration and braking. Its well researched and all the great racing names discuss it in their books. If you want to understand the physics a very technical book "Motorcycle Dynamics" by Vittore Cossalter discusses it in every detail. Have a look at chapter 3 (link below). Rectilinear motion of motorcycles and 3.2 The CoG and the moments of initertia

http://books.google.co.uk/books?id=rJTQ ... q=&f=false