Cycling UK Forum

Ok, I know "directionalness" isn't a word. At least not yet.

I've got Marathons. The "ordinary" ones ("Greenguard"?)

I've just noticed that my front one is mounted the wrong way round, according to the arrow. This bike has disc brakes, so I can't just turn the wheel around. It's been like that for about 1500 miles.

Does it matter?

Not so you would notice obviously If it has tread then I guess that it may be more effective running the correct way but on something as hefty as that I doubt you'll feel any lack of performance anyway. When it needs to come off swap it round.

Just doing a bit more Googling, and came across this fascinating quote from the manufacturer of my actual tyres:

Why are so many treads direction dependant? In the case of a road tire the rolling direction is mainly important for aesthetic considerations. Tires marked with arrows simply look more dynamic

from here:
https://bicycles.stackexchange.com/ques ... 2074#52074

I generally find Stack Overflow a reliable resource.

My bike is a road bike with 700c wheels, by the way.

As ever these days. If you're a worrier then worry about it. If not, ride on....you WILL be fine.

Friend of mine with Marathons fitted by a cycle shop. They have been on for a good few years. The first thing I noticed about them when I saw the tread was they were fitted the wrong way around. 2 bikes his and hers and fronts and backs. He's very finicky with stuff being correct so it probably niggles him as he mentions it to me frequently when we meet up. I pointed out he could correct the fronts by turning the wheels around but it's a tyre off job to do the rears. I bet he's waiting for a fairy visitation.

I wouldn't let it worry you. Some tyres are marked with opposite direction arrows for front wheel or rear wheel use. Bit confusing for unicyclists

I have my tyres marked for both direction and position, and direction arrows on the tubes.

If tyre & tube are always in the same position relative to one another it makes it easier to locate the debris in the tyre once you've found the puncture in the tube. (I didn't bother until my eyesight had made the job harder.)

LancsGirl wrote: ↑11 Aug 2022, 5:54pm I've just noticed that my front one is mounted the wrong way round, according to the arrow. This bike has disc brakes, so I can't just turn the wheel around. It's been like that for about 1500 miles.

Does it matter?

I wouldn’t feel right about it until I’d reinstalled the tyre with the arrow pointing the right way and gone another 1500 miles, thus zeroing out the error, but that’s just me.

At work the other day, I was checking over the bike of our CEO (he had it made for him). Having a keen eye for detail, I noticed that his rear tyre was on the wrong way around. The 'arrow' tread pattern was pointing down at the very back - against the correct forward pattern at the front. I mentioned it to him in passing, and he said he'd had a puncture whilst on a ride. He had to turn the bike up on its handlebars and saddle to get the wheel off, and had put the tyre back on with the tread pointing forwards - forgetting, of course, that the bike was upside-down! 'It won't matter too much on that bike, anyway,' he said. I guess not. Though it's a tourer with 1.4" wheels. As long as he's happy with it, I suppose.

I've done the same thing myself, in the days before I got a maintenance stand. Bought two new tyres, turned the bike upside down to do the replacements, got the tread pattern facing forwards.... and then realised the error when I turned the bike up the right way again! Easy mistake to make. But I couldn't live with that. So... did it all again. I probably could have just turned the front wheel around - but then it meant messing with the computer thingy on the spoke, etc. Nope. It had to be right

I seem to remember reading that it is important to get tractor tyres the right way round. If you notice the tread pattern on rear tractor tyres it is approximately chevron shaped, with the chevrons pointing forward in the direction of rotation. I guess that may well be important with the deeply indented tread having to deal with thick gloopy mud at times. Can't be nearly as important for bike tyres, can it?

Should we be concerned that there is a 'right way round' for the balls in cycle hub bearings

rjb wrote: ↑11 Aug 2022, 6:28pm Friend of mine with Marathons fitted by a cycle shop. They have been on for a good few years. The first thing I noticed about them when I saw the tread was they were fitted the wrong way around. 2 bikes his and hers and fronts and backs. He's very finicky with stuff being correct so it probably niggles him as he mentions it to me frequently when we meet up. I pointed out he could correct the fronts by turning the wheels around but it's a tyre off job to do the rears. I bet he's waiting for a fairy visitation.

I wouldn't let it worry you. Some tyres are marked with opposite direction arrows for front wheel or rear wheel use. Bit confusing for unicyclists

Then the txt on the hub would be the wrong way

yes, fairly irrelevant on road tyres, much as any tread pattern is generally.

At most, if you happen to be cycling through a thin layer of slightly gloopy liquid the correct direction will help force that liquid to the sides slightly better.

Direction is far more relevant in offroad, particularly MTB where the knobs are specifically ramped on one side to reduce rolling resistance but kept closer to perpendicular on the other to provide more grip under braking.

I have always assumed water would be shed more easily from tyres mounted in the correct direction, giving more grip in wet conditions. When mounted the wrong way water could build up between the tyre and the road, reducing grip.
As noted above tractor and tyres on similar vehicles are mounted with the chevrons pointing in the direction of rotation for similar reasons - more grip.

It seems a bit perverse not to follow the manufacturer's guidance on this for no particular reason. Just put the tyres on the "right" way every time and you'll never have to think of this again. As a bonus, you'll have even less need for a word like directionality.

See recent discussion.

On the road it makes no difference, even in the wet.