Flipping tyres?

**GSVR** · 22nd June 2007, 12:46

Thought I'd start this thread becuase I can...

What are other racers opinions on flipping tyres (slicks) around when they wear out one side? If they are the same both ways why does the manufacturer put an arrow on the sidewall like it actually means something?

**cowpoos** · 22nd June 2007, 12:54

I think...the rubber is laid on the carcuss in a certian direction...which makes it more ideal for the tyre to turn the opposite way...I'm not totally sure...that was something someone mentioned to me once...but I know of top racers that turn tyres around....I'm sure there is an ideal..and someone will know!

**Tim 39** · 22nd June 2007, 13:02

I'm not too sure about this, I have also heard about the way the rubber is laid or something. I personally wouldnt do it in the nationals but may consider doing it through the off season to get a bit more life out of tyres.

**Toast** · 22nd June 2007, 14:58

Was just speaking to a reputable tyre fitter...

Seems that it's to do with the way that the belts are laid down in the construction of the tyres.

Back in the day of cross-plys it was unthinkable to run them in the opposite way to recommended (kinda need to visualise the way in which the belts overlap (cross ways) to make sense of it).

With all of these 0-degree belt radial things though, the belts are run length ways and across the tyre, so the underlying construction is basically symmetrical and will deal with the forces of acceleration, braking and cornering the same whichever way it is rotated.

The fact that manufacturers still recommend a certain direction of rotation is perfhaps just based on the outer rubber tread pattern? I did find a Michelin slick in the shop that had no recommended direction of rotation (but also a Metzeler slick that did).

That's my impression of the matter anyway.

Anyway, if it's good enough for the top dudes, I'll give it a go.

**The Stranger:Me** · 22nd June 2007, 15:52

Originally Posted by cowpoos

I think...the rubber is laid on the carcuss in a certian direction...which makes it more ideal for the tyre to turn the opposite way...

Was told the same thing by an importer.
However I note on the Conti site that they say they have found better wear when running the front road attacks backward and are changing the moulds to reverse the arrows.
That said, it isn't the rear and taking the big power.

**cowpoos** · 22nd June 2007, 15:57

Originally Posted by The Stranger

That said, it isn't the rear and taking the big power.

the front tyre handles the braking forces...which are a hell of alot higher than accelerating forces...you can slow down faster than you can speed up!!

maybe this is what conti have discovered...Jayracer37 might have a insight into this as he's testing the race tyres for conti

**The Stranger:Me** · 22nd June 2007, 16:44

Originally Posted by cowpoos

the front tyre handles the braking forces...which are a hell of alot higher than accelerating forces...you can slow down faster than you can speed up!!

Good point.
I don't care what Dover says, you a clever bugger.

**codgyoleracer** · 22nd June 2007, 17:02

Flipping them depends on your circumstances. The newer zero degree rubber seems to be able to handle it OK, & if your low on rubber or shredded one side of your tyre & dont have a back-up , then flipping them can be a safer faster result. It beacame a habit for me when riding Pukekohe track a bit & the right side of the tyre would change its shape pretty quick. The arrows are on there for a reason though I am sure of that.
When flipping them beware that they can feela little funny for the first few laps as the balled rubber on them takes a little time to reorganize itself. Also keep an eye on the joints in the treaded part of the tyre for separation.
The stopwatch has never provided any clues on if they are slower the wrong way round in my experience - so grip levels appear to be the same.

**kickingzebra** · 22nd June 2007, 17:10

Its easier to flip a pancake.
I flipped the fronts at the nationals at levels, as it was chomping them out, and 600ss only allowed 1 front and 2 rears. Went faster, to no adverse affect on apparent grip and braking. But the I ain't no JayRacer37. He is way too pretty.

**rwh** · 22nd June 2007, 17:20

Originally Posted by codgyoleracer

The arrows are on there for a reason though I am sure of that.

To sell more tyres?

Or more seriously, perhaps people will think the tyres without arrows aren't as good as those with arrows, because they must be less optimised, right?

Richard

**HDTboy** · 22nd June 2007, 17:26

I know with car slicks that tyres delaminate if you run them in the wrong direction. Don't know if this translates to bikes as bike tyres have more development time put into them

**k14** · 22nd June 2007, 17:29

I think it was in the movie faster (or it may have been in some other motogp related tv show) that now for the tyre manufactures have gone so far as to being able to change the traction attributes of the tyre in the forward and reverse direction (eg acceleration and braking). Thus by reversing the tyre you would be degrading one aspect and improving the other. Not sure if we're good enough to do this or if infact it is only used on motogp tyres. Makes sense though, sorta...

Me, I've never flipped them, always ran them the way the arrows pointed.

**Kickaha** · 22nd June 2007, 17:49

Originally Posted by Toast

Back in the day of cross-plys it was unthinkable to run them in the opposite way to recommended (kinda need to visualise the way in which the belts overlap (cross ways) to make sense of it).

it was actually very common to run them the reverse direction on opposite ends of the bike as a lot of tread patterns weren't directional, you ran it one way for drive and the other for braking

Most it was due to the tread splice as the forces acting on it are different front to rear,the direction of rotation was designed to push it together rather than pull it apart