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Cobrabiker

Uni-directional Tyre Fitted Opposite Direction

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Just realised that my bike had a front Michelin fitted on the opposite direction, and had rode on the wrong direction for almost 1000 km, I notice also there is a rotating direction on the rim, is it important for the rim to be in the same direction?

My speed was 140 to 220km, average speed around 160 to 180, and with a wrong direction front tyre, will the tyre burst if going at high speed continuously? Has it damage the tyre inner belt? I know for fact that this will cause much accident in the rain, but know nothing about the rest, advise please.

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I've had experience with unidirectional front and aft tyres on small bikes - they are designed to give a bonus to acceleration and braking, while reducing rolling resistance, hence the threads are designed to rotate in one direction.

If you reverse it you simply lose the benefits of the thread design, and are running less efficiently. This being the XXI Century they would not blow up in your face, but they may be wearing faster just from common sense physics.

Whomever did that to you should stick to cheap tyres!

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I heard from a factory rep for Dunlop that running a directional tire in reverse would void the guarantee and cause separation. I never heard about the other accel/decel thing but you should be reading on the tire manufactures website for that info and it is is not made clear there then call or email them....They are gonna be the only one who can give the official word.

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It was a mistake done by the mechanic. And so reversing it would it increase rolling resistance, more friction, more heat, and eventually blows up. I guess I was lucky, it hasn't blow up yet. BTW Vision, it is 2nd hand bike, came fitted with it by the previous owner, so no warranty anyway.

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It's all about performance & wear issues, technically not safety issues except where rain is concerned..

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It was a mistake done by the mechanic. And so reversing it would it increase rolling resistance, more friction, more heat, and eventually blows up. I guess I was lucky, it hasn't blow up yet. BTW Vision, it is 2nd hand bike, came fitted with it by the previous owner, so no warranty anyway.

Cobrabiker,

What you describe, highlighted above is highly unlikely. It is correct that if the tyre is a directional one that it was designed for use in that direction to get Optimum performance, in particular on wet roads and for a motorcycle tyre running it in the incorrect direction is highly unlikely to cause a heat problem or a failure associated with heat. In fact, You are far MORE LIKELY to cause heat damage to a tyre due to underinflation and theres shitloads of underinflated tyres in thailand and the rest of them are overinflated. :)

Having said that, in a car tyre standard type they have a symmetrical tread pattern which is generally the same across the entire width of the tyre. The directional tyre on a car (asymetric tyre) the tread pattern on them generally changes across the width of the tyre, as different parts of the tread has different functions, ie: the outside edge has stiffer, larger tread blocks which help with cornering and the inner are generally smaller and designed to move water and improve grip in the wet. Also the middle blocks tend to have a continuous rib to help with straight line stability. The motor cycle tyre is different to this for obvious reasons.

Fitting a directional tyre the incorrect way can increase road noise and reduce directional stability, but some people won't even notice that.

Also and finally, it is possible that when you go and reverse the tyre on the rim to run in the direction it should be, that you may find the tyre may not roll smoothly, as a wear pattern may have developed and that infact can be directional, if that makes sense. Its no different if the tyre had been run correctly for several thousand kilometres and then reversed, the same rule applies.

im not sure i have explained this that well, but hopefully it helps.

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and if you turn the wheel around it's very hard to get the chain back on.

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and if you turn the wheel around it's very hard to get the chain back on.

Well theres that too....u tool :)

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Its simples, It would not grip the road in the wet, As it was designed for, so it would be like riding on ice in the wet. take care.

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It will not make any notable difference in dry weather. Things mentioned above are true, but they make so little difference it doesn't matter from a practical stand point.

However, in the wet, it does matter quite a lot. I would not recommend riding at any sort of speed in the wet.

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Hi Neverdie and everybody, I do notice that the front tyre is nosier and has more vibration. I read in another forum that a police car got the tyres in the wrong direction and got in to accident in the rain, and also commented that most vehicles got into accident in the rain got their tyres mounted in the wrong direction, so it is better to check it yourself rather than trusting your life into someone's hand, as human makes mistake.

So I think the major problem is on wet road. Generally I think riding at normal legal speed should not be a problem, the Michelin is Z rated, but going reverse and especially at high speed of above 200km/hr, can it still handle the heating problem?

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good post #6 Neverdie

Had similar exp with front tyre, incorrect/reverse fitting was picked up (and therefore failed inspection) at Vehicle Testing Station in NZ at annual 'Warrant of Fitness' inspection. Tyre had been on several months and I think 4000km on a big sportsbike. Most of those kms were 'open road' and I do like my high speed, plenty of wet weather riding too.

Dealer who'd supplied/fitted accepted blame and replaced it.

I'll be honest and say I'd never have noticed till the arrows were pointed out to me.

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So I think the major problem is on wet road. Generally I think riding at normal legal speed should not be a problem, the Michelin is Z rated, but going reverse and especially at high speed of above 200km/hr, can it still handle the heating problem?

Why the question? Just have it remounted correctly, surely you're not considering using it in the current fashion knowing now it is not correct?..

Yes vibration is one of those performance issues noted..Can be a big problem at speed on any vehicle let alone a bike.

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I'll be honest and say I'd never have noticed till the arrows were pointed out to me.
Most unidirectional tire tread patterns are unmistakable as they also form an arrow in a sense, pointing towards the direction of rotation, kind of hard not to notice on a bike. Don't mean to be critical but it concerns me that people who are not capable of noticing that are even riding bikes in the first place..

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Hi Neverdie and everybody, I do notice that the front tyre is nosier and has more vibration. I read in another forum that a police car got the tyres in the wrong direction and got in to accident in the rain, and also commented that most vehicles got into accident in the rain got their tyres mounted in the wrong direction, so it is better to check it yourself rather than trusting your life into someone's hand, as human makes mistake.

So I think the major problem is on wet road. Generally I think riding at normal legal speed should not be a problem, the Michelin is Z rated, but going reverse and especially at high speed of above 200km/hr, can it still handle the heating problem?

Z rating can probably handle 200kmh without overheating, even going wrong way.

But traction is hugely decreased, dry and wet, so have it installed the right way asap. Then break it in gently (120kmh) for 50-100km.

Did it wrong on a Corvette, a car with 4 different tyres since not same size front and rear and all directional. Handled very strangely. Goodyear said install them properly, break them in again, and good to go

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BANGKOK 27 July 2017 13:54
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