rotation arrows on conti tyre,s

I run Conti GP 4000s IIs and have had them on the wrong way on numerous occasions. Haven't experienced any decrease in performance or grip. I hate cycling on the chocolate path though, whether my tyres are on the wrong way or not...

Well, thank you everyone

I ended up having some spare time so took the tyre off and turned it around.

The tyres are Conti Touring Plus, so they have tread, proper chevrons, but no "arrow on the side" rotation arrows.

Funny thing is, it did feel like it made a difference. Part of my commute is on a cobbled-ish path in Bristol called the Chocolate Path, and I do feel much more stable on it with the chevrons pointing forward as I look down at them.

Hmm - so is it just psychological...?

Not sure where I read it, it may even have been on here, but a few months ago I read a piece about tread and road tyres. The author had gone to the trouble of asking some of the big manufacturers about tread.

Overwhelmingly the manufacturers all pretty much stated that for road tyres, the contact patch of a road bike tyre is so small that in the wet aquaplaning was not really a consideration and that the main reason for having tread was to allow the tyre to deform more easily around bumps/variations in the road surface, and consequently provide more surface area in contact with the road. Channeling water (and the risk of aquaplaning) apparently only becomes a problem when the contact area is large (like a car or motorcycle tyre which is huge in comparison to the few square cm that a road bike has).

Specialized even went as far as saying that even just roughing up slicks provided enough "tread" to improve grip and that in most cases this should be enough.

So to answer your question, I doubt it really makes much difference, it "feels" wrong to accept this as we're so used to hearing about how important tread patterns are but don't forget, that advice is aimed at cars, not bicycles.

Conti's, a lot of them, have a some weird semi-circle design on them. Kind of like a wedge. Wide part goes to the rear and the thin to the front.

I assume you are using road tires.

I use 'Continental Grand Prix TT' tyres when training in an outdoor velodrome. They have rotation arrows on them but no tread at all. I rotate them as otherwise I'd only get half the use out of them. Never had an issue with them being the wrong way round, although I might start working that into my list of possible excuses for when I have a bad day

I think there's some value in a bit of tread on more touring-type tyres at this time of year when you can get a sort of thin, slippery sort of paste of mulched up wet leaves on the roads. I have 32mm Marathons and I think they're maybe a bit better in that sort of stuff than if they were slick.

For water on the roads though I think it's pretty widely accepted there's no benefit, especially on thinner racier tyres. Personally I still make sure they're on the right way because I'm nerdy enough to care!
Even if they don't have arrows it's easy enough to tell on tyres with any sort of chevron-like pattern on, which seems to be most of them.

All my recently bought Continental tyres seem to have no rotation arrows. Even when they did have them they were always difficult to find. Likewise recommended tyre pressures are difficult to read on the tyres. Apart from that Gatorskins have served me well for several years club riding and touring. Some were even being used in the club's last road race.

I have GP 4 Seasons on my fixie, to change the gear I have to remove the rear wheel and turn it around, so the tyre gets used in both directions. I can confirm it makes no difference at all.

We is postgrammar world now innit. Theres only one rule for apostrophes: stick one in if you think it look's good.

About as much difference as there is between a comma and an apostrophe

They don't make a blind bit of difference.

Can I resurrect this one, please?

My Continental Touring Plus tyres don't appear to have a rotation arrow. Does it matter which way round I put them, or is it just aesthetics?

My bike is a Mongoose Hybrid, used for commuting on tarmac.

I think this question is intended purely to make me feel guilty about not cleaning my bike.

You are correct in your assumption re direction of rotation.

Does it make a difference? Well, possibly - the footprint of 700 x 23s is very small, so in terms of clearing water away from the road surface / tyre interface via the "siping" moulded into the tyre tread on a narrow tyre, it's probably not a big factor. As the tyre contact area gets bigger, so the siping becomes for important, but it's probably not the most important reason to fit a road tyre "right way around".

Some tyre manufacturers make the casing of the tyre itself so that it resists loads from braking or from pedalling, or even from cornering, better if it fitted the right way around, so from that perspective, it's a good idea to have it right.

If you are a mechanic in a shop, best to get it right as if the rider takes a dive & you were the last person to fit the tyre, some smart lawyer could have a field day with you if the tyre was on the rim back-to-front ...

Off road (incl. CX) it can make a big difference to how the tyre works against an uncertain, claggy or generally un-made-up surface ... you need the tread oriented so that it clears loose or wet material to the side, so hopefully taking you down to a firmer footing below ...

Some of my mtb tyres have opposite rotation depending on whether fitted to the front or rear . . . I guess it does matter as it impacts tread pattern dependent grip.

As I understand it rotation direction is to do with clearing water from under the tyre. If you think of a V-shaped tread on a car tyre the point of the V should hit the road first so water is squeezed up the arms and out of the side of the tread. Doing it the other way would push water into the tread, possibly ending up with an aquaplaning situation.

That's cars though. For road tyres on bikes I'm not sure it actually makes much of a difference, as the contact patch is so small and speeds so low I'm not sure you could aquaplane in that way. Rubber compound is a more likely determinant of grip.

I'd still install them the right way round. Aesthetically it just looks right with the tread pattern pointing "forward" on the top of the tyre when you look down at it from the saddle.

Probably not to the rolling resistance but maybe to the grip in the wet - the tread pattern is designed to funnel water off the tyre and presumably it's direction-specific.

(It should be said that Sheldon Brown is very sceptical about the value of tread on road tyres, arguing that with a tyre at 100psi you have to do over 100mph before you can make it aquaplane: http://sheldonbrown.com/tires.html)