Running Directional Slick Backwards?
#1
Burning Brakes
Thread Starter
Running Directional Slick Backwards?
I have a set of Hankook C51, 275/5/18 square. This is their medium compound road racing tire. The tires have no tread, just two circumferencial grooves. And yet the tires are directional, an arrow on the sidewall clearly points out direction of rotation.
In the past I've always been told the only reason modern radials are directional is due to tread pattern. But these tires have no tread, so why are they directional?
If its for reasons of performance then I wouldn't worry about running them backwards, but if its a safety issue then of course I'd be concerned. The Hankook website says nothing on the matter.
Thoughts?
PS: this tire is absolutely awesome. Fantastic grip, wear well and never get greasy - and cheaper than Hoosiers to boot. Love the tire, but if I can run them backwards with no safety concerns then I'd love them even more.
In the past I've always been told the only reason modern radials are directional is due to tread pattern. But these tires have no tread, so why are they directional?
If its for reasons of performance then I wouldn't worry about running them backwards, but if its a safety issue then of course I'd be concerned. The Hankook website says nothing on the matter.
Thoughts?
PS: this tire is absolutely awesome. Fantastic grip, wear well and never get greasy - and cheaper than Hoosiers to boot. Love the tire, but if I can run them backwards with no safety concerns then I'd love them even more.
#2
Team Owner
If you're wanting to rotate them due to wear, then you should be able to have the tires dismounted and moved to the other side of the car. As long as the directional arrows are pointed in the same direction, the "old" outside edge of the left tire will be on the inside edge of the right side tire. Extra work for a tire shop, but it does keep the tires rolling in the right direction.
#3
Melting Slicks
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I don't have specific experience with the Hankooks, but when Kumho Victoracers were new they had an issue with the tread peeling off. Followed REALLY soon by instructions about the direction of rotation. Contact Hankook?
#4
Burning Brakes
My experience....the manufacturer will not ever tell you to run a tire opposite of the sidewall markings. I've done it on directional R comps (not on Hankook's) and had zero issues. Many others here do it as well with no problems.
With that said, the carcass plys are directional and will tighten under braking or loosen, depending on direction. Not sure how big a factor this is on your tires but I used to work for a tire manufacturer and this was clearly communicated to us with regard to direction.
With that said, the carcass plys are directional and will tighten under braking or loosen, depending on direction. Not sure how big a factor this is on your tires but I used to work for a tire manufacturer and this was clearly communicated to us with regard to direction.
Last edited by ZedO6; 10-30-2014 at 07:25 PM.
#5
Race Director
My experience....the manufacturer will not tell ever to run a tire opposite of the sidewall markings. I've done it on directional R comps (not on Hankook's) and had zero issues. Many others here do it as well with no problems.
With that said, the carcass plys are directional and will tighten under braking or loosen, depending on direction. Not sure how big a factor this is on your tires but I used to work for a tire manufacturer and this was clearly communicated to us with regard to direction.
With that said, the carcass plys are directional and will tighten under braking or loosen, depending on direction. Not sure how big a factor this is on your tires but I used to work for a tire manufacturer and this was clearly communicated to us with regard to direction.
I have run every tire I ever had on my Corvettes tread or not in both directions, no issues.
When Kumho had the separation issue they specifically said to reverse the direction to help with the problem. They did not have direction arrows, however.
If some have arrows and some don't, are the carcass plys wrapped "better" on the ones that do not have arrows? Does not make sense to me.
#6
Tech Contributor
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Interesting about the plys. Had not heard that.
I have run every tire I ever had on my Corvettes tread or not in both directions, no issues.
When Kumho had the separation issue they specifically said to reverse the direction to help with the problem. They did not have direction arrows, however.
If some have arrows and some don't, are the carcass plys wrapped "better" on the ones that do not have arrows? Does not make sense to me.
I have run every tire I ever had on my Corvettes tread or not in both directions, no issues.
When Kumho had the separation issue they specifically said to reverse the direction to help with the problem. They did not have direction arrows, however.
If some have arrows and some don't, are the carcass plys wrapped "better" on the ones that do not have arrows? Does not make sense to me.
As for a slick being directional it must have something to do with the tire's construction. They may be using some sort of construction that lowers rolling resistance in a specific direction. Reversing direction might cause more heat build up in the tire but that is a pure SWAG.
Bill
#7
Racer
As for a slick being directional it must have something to do with the tire's construction. They may be using some sort of construction that lowers rolling resistance in a specific direction. Reversing direction might cause more heat build up in the tire but that is a pure SWAG.
Bill
Bill
#8
Drifting
Actually, there may be some truth to that. Formula 1 found out the hard way last year what happens when you run a "directional" carcass backwards. If you're not familiar with the associated incidents, look up "2013 Silverstone Grand Prix tires" That should get you close.
#9
Drifting
from tirerack ... Ventus Z214 tires feature directional rotation arrows branded onto their sidewalls to identify correct mounting rotation that will enhance tread splice integrity and durability. Following the rotation arrows, the use of a symmetric tread design allows Ventus Z214 tires to be mounted on either side of the car (and later be remounted inside out to further extend their life).
#10
Burning Brakes
I always thought there was concern of belt shift when reversing a radial that had already been run in a certain direction. I would think this is even more important for a race tire that sees extreme loading.
#11
Burning Brakes
Thread Starter
Well - better safe than sorry so I'm not going to try reversing them. Kind of sucks - many tracks are harder on left side tires (clockwise tracks). It's nice to rotate side to side at the end of each day. I do it with the Continental Hoosiers but alas not with the Hankooks...dang.
#12
Burning Brakes
Well - better safe than sorry so I'm not going to try reversing them. Kind of sucks - many tracks are harder on left side tires (clockwise tracks). It's nice to rotate side to side at the end of each day. I do it with the Continental Hoosiers but alas not with the Hankooks...dang.
#13
Melting Slicks
from tirerack ... Ventus Z214 tires feature directional rotation arrows branded onto their sidewalls to identify correct mounting rotation that will enhance tread splice integrity and durability. Following the rotation arrows, the use of a symmetric tread design allows Ventus Z214 tires to be mounted on either side of the car (and later be remounted inside out to further extend their life).