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Morning Gents,

I've been hunting around for some tyres and tossing up between some new high performance road tyres like the Kumho KU36s or Federal 595 RS-Rs or second hand semis (having no luck with semis it seems)

I'm wondering if anyone has used the RS-Rs as I think I've come across a decent deal, 4x 235 R17s for $640 delivered. Normally the RS-Rs are a bit more expensive than the KU36s but this guys doing a bit of a deal to move them before tax time I'd say.

So has anyone used the RS-Rs? I know plenty of you attest to the KU36 being an OK tyre for light track duties (I'm running an S13 with only 160+ rwkw)

I need to make a call this morning so the guys can pack them into the truck for their trip to Winton.

Opinions?

Edited by ActionDan
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RSR's were about 1 second quicker than the ku36 around lakeside for me. they did chew out a lot faster as i was driving them on the road aswell, but that sounds like a pretty awesome deal, DO IT !

as a comparison, KU36 felt nicer as you approach the limit, the RSR's felt a bit funny and did not give as much feedback, but had better overall grip so thats the tradeoff.

Edited by scooby36

Yeah I see the KUs have a tread wear of 180 and it's 140 for the RS-Rs wasn't sure just how big a difference that would make. My car isn't bad on tyres but that's been on very old (so quite hard) R comps.

What sort of life did you get out of them?

EDIT: I have another set of cheap 17" rims and tyres for the rare occasion the car gets driven on the road so it will be purely track ks for these tyres.

Edited by ActionDan

Hmm, bit of a difference then but as I wont be doing the 10,000 road k's I'd expect another few track days and 8 or so track days would be like 2+ years for me lol

I think they should be alright value for the money then :D

Cheers guys

http://www.wheeltechwheels.com.au/

These guys are running these on special for a month or so :)

Speak to Laurence and tell them Dan referred you.

These guys are at Winton monthly so you can collect from there, he also goes to Wakefield a bit.

For the price he's actually driving them up to Wodonga for me, how's that for service lol.

Edited by ActionDan

I've used the federals on an EMO.

They were pretty good. Better than a street tyre - not as good as an R Comp.

Pretty much what you'd expect really.

That pretty much sums them up. Great bang for buck for those wanting to do both street and track on the one tyre.

I get around 12 to 15 kay from a set with a few track days thrown in. They are surprisingly better in the wet than I expected too.

The RSR were not as progressive as the KU36. But provide more grip for longer. The KU36 go off pretty quick on the track, the RSR will give you 3-4 laps around PI. KU36 start to slide after 1 lap.

I did 20+ track days to a set of 255 in the rear of the car last year. Went through 2x 235 sets on the front. The poor set of 235 all round KU36 only lasted 8 or so track days.

I used a set of RSR's at the nurburgring nordschleiffe of all places! they were pretty good for most of a lap but went off if you pushed it too hard and got a bit slipper. bearing in mind the ring is 20odd kms long and fast as fk!

seems like a good deal. I still reckon the dunlop Z1* are better though and are similar money in that size from tirerack.com.

I've driven on the track with cars with KU36's, RS-R's and Z1 Star spec's.

IMHO the RS-R's are the best followed very closely by the star spec's.

I found the RS-R's to be the best all rounder as they work well from stone cold, have R comp like qualities in the way they lose grip when the slip angle increases but they do over heat more quickly than the KU36's (odd one of you above had the exact opposite experience). The RS-R's have a noticably softer sidewall than R comps which makes the barely tramline at all even on my car - 285 RS-R's all round and the car only weighs 1140kg (will be at WTAC in open class :))

The star specs I went passenger in an EVO being driven in a very spirited manner on a twisty road and was unimpressed. I did, however, drive them on the track on a modded turbo mx5 and was very very impressed. They gave way in a predictable manner but still felt more like street tyres than R comps when compared to the RS-R's but not by much.

If you bought the RS-R's or the star specs and had driven both of them in a relatively short period of time you'd find it hard to tell the difference.

My experiences with the KU36's are different to the above. I had a set of them and i've driven a number of cars that had them on the track. I found them useless when cold, great when hot, not nearly as progressive on the limit as the RS-R's but the absolute grip of these tyres when they were hot was remarkable. When they got older they became very difficult to get hot particularly on the road at times making them a little on the dangerous side. As a result I wouldn't buy another set.

My experiences with the KU36's are different to the above. I had a set of them and i've driven a number of cars that had them on the track. I found them useless when cold, great when hot, not nearly as progressive on the limit as the RS-R's but the absolute grip of these tyres when they were hot was remarkable. When they got older they became very difficult to get hot particularly on the road at times making them a little on the dangerous side. As a result I wouldn't buy another set.

which is different to my experience on KU36 as well!

I found them best from cold and would purposely not do any warm up on the out lap. 1 corner and they are at their best. 3 laps and they were a bit hot and squirelly. The battle was to stop them getting too hot. But Brisbane weather and track conditions are alot hotter than down south. And this was on a 1540kg Supra. 245 & 275 tyres. So its probably a matter of car and conditions.

I also found the performance didn't deteriorate over their life. I was basically going faster every time I went back to the track.

Very progressive on the limit and easy to control.

I got about 15,000km and around a dozen track days out of them. Even then, it was only the rears that wore out. Fronts were still going strong. Great on the road and very good in the wet. I drove home from Sydney when they were well and truly on the TWI in heavy rain almost the whole way - no problem at all. Also used them on my Legnum as a pure street tyre.

Edited by hrd-hr30

...I found them best from cold and would purposely not do any warm up on the out lap. 1 corner and they are at their best. 3 laps and they were a bit hot and squirelly. The battle was to stop them getting too hot. But Brisbane weather and track conditions are alot hotter than down south. And this was on a 1540kg Supra. 245 & 275 tyres. So its probably a matter of car and conditions....

this is what I didnt as well. go out hard to start. by the third lap they are screaming at you. on my car at least, that center tread line on the ku36 moved around like a wet rag after 2 laps. hot pressures from 34-38. the sidewall on the ku36 is much softer than RSR. i find you can run the RSR at lower pressures 32-36 and get heaps of laps out of em. I also found the ku36 got better after and better with use, to the point where they just screamed and pushed.

Me thinks baron has some shares in dunlop??? heahea

I have seen quite a few of the mx5 guys running the Z1's. I didn't really see them as a tire for heavier cars. what are the sidewalls like in comparison to the ad08 (have you felt them while off the wheels?).

those and the hankook are soooo cheap it is almost worth trying, it is just that the RSR hard to pass up.

Yay :)

They're a bit dirty from being rolled down the driveway but they look pretty decent. I love new rubber.

Now to get them on the rims and get to the track!

Interestingly, when measured against old Potenza R comps, these are a bit wider, but it might be due to the little kicker lip on the Fed's that protects the rim face.

post-23873-0-84455100-1308528794_thumb.jpg

this is what I didnt as well. go out hard to start. by the third lap they are screaming at you. on my car at least, that center tread line on the ku36 moved around like a wet rag after 2 laps. hot pressures from 34-38. the sidewall on the ku36 is much softer than RSR. i find you can run the RSR at lower pressures 32-36 and get heaps of laps out of em. I also found the ku36 got better after and better with use, to the point where they just screamed and pushed.

Me thinks baron has some shares in dunlop??? heahea

I have seen quite a few of the mx5 guys running the Z1's. I didn't really see them as a tire for heavier cars. what are the sidewalls like in comparison to the ad08 (have you felt them while off the wheels?).

those and the hankook are soooo cheap it is almost worth trying, it is just that the RSR hard to pass up.

lol, no shares in dunlop but I've always liked the Dz03G over most other semi's overall. and I reckon of the "S-tyres" or whatever we call this new segment of super high-po street/track tyres, the Z1 seemed to me to be the best compromise between street/track/grip/noise/wear/cost etc. the RSRs are great too though. I'd say the Z1 sidewall is on par stiffness wise with the AD08. having said that on track they did seem to like higher than normal pressures which may indicate they are a bit softer in sidewall. they were great around 35/36psi hot but when I dropped them a bit down to more semi-slick like pressures they seemed to suffer a bit.

the main reason I rate the Z1* over AD08 and AD07 is they are a shitload cheaper and I thought they were a bit better too. don't get me wrong, AD08s and AD07s where one of my favourite road tyres till i used the Z1*. and they are still well up there.

Talking to a couple guys who are in the MX5 scene it seems as if the KU36 is alot easier to get temperature into then the 595 RS-R.

My housemate who has a turbo NA really did not like the 595 RS-R and says it was some of the worst understeer he's ever had.

We put it down to the weight of the cars is too low to properly work the front tyres into that optimum window of operating temperature .

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