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Track Report: Rota Rims And P-cup Slicks..


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although if we're honest, 99% of cast wheels are cheap junk u pick up from ur local bob jane to make ur laser look speccy!

my original posts have been deleted, but my there point was, you are racing a heavy supercar around a track, you simply cant use what ur average car uses, rotas are just a glorified CSA, monza etc etc which just so happen to come in bigger sizes and offsets, they are targeted at a different market, but they are no different besides that. its one thing to put them on a street car, a low end drift or grip car (although i wouldnt recommend it), but to put them on a track GTR

Sounds perfectly reasonable.

I'm not suggesting cast is better or even appopriate; but if 99% of cast wheels out there are made from this material, maybe we shouldnt be shooting down Rota (or any other cast rims). I've been using the wrong rims, and pushing them too hard vs their intended purpose. My fault. I'm not prepared to blame the rim automatically, as some people so quickly have. We can learn something here if it doesnt turn into a shitfight, heaps of guys use such rims on the track, i've seen it myself.

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Incidentally a UK magazine tested a wide selection of rims to destruction , and then graded them on weight / strength / price and they chose the ROTA 's as the best option based on lightest and strongest for the lowest price.

perhaps ROTA distributor can provide the anonymous UK magazine's article? Would be an interesting read.

Their testing methodology and the actual conclusion and criteria would be worth seeing. throwing price in there could easily skew results. ie something light, cheap but relatively weak could perform as well in strength:weight:cost as a good quality forged wheel thats light, expensive and strong.

I totally understand the ideology of using cheap parts that may not last as long as the high quality (expensive) parts... and just being prepared to replace them when they break etc... throwing wrecker bottom ends in instead of going the rebuild route for example... often that way can work out cheaper in the end... however I would hate to see those rims fail and have you put the 35 into a barrier... the whole cost argument goes out the window then

forgetting lap times, anything that keeps you on the black stuff is where you want to throw the cash first... in my humble opinion:)

very good of you to report the cracks tho... too many times these sort of threads go unfinished as the OP never comes back to give the full story

although if we're honest, 99% of cast wheels are cheap junk u pick up from ur local bob jane to make ur laser look speccy!

my original posts have been deleted, but my there point was, you are racing a heavy supercar around a track, you simply cant use what ur average car uses, rotas are just a glorified CSA, monza etc etc which just so happen to come in bigger sizes and offsets, they are targeted at a different market, but they are no different besides that. its one thing to put them on a street car, a low end drift or grip car (although i wouldnt recommend it), but to put them on a track GTR

The majority of enkei rims are cast and are often confused with forget rims, they are also light and strong.

Rays engineering also makes cast rims for gram lights and others.

The majority of enkei rims are cast and are often confused with forget rims, they are also light and strong.

Rays engineering also makes cast rims for gram lights and others.

Enkei use a special technique to make light, strong, low price cast rims so they are not the same as your run of the mill cast rim such as a Rota or tyre shop cheapie, google it.

I have been told that Rota make OEM rims for toyota, can someone confirm this?

http://tinyurl.com/23qjzjd

Enkei use a special technique to make light, strong, low price cast rims so they are not the same as your run of the mill cast rim such as a Rota or tyre shop cheapie, google it.

I know, read hes post then mine, he was saying that all cast are junk which isn't true.

Yep. I ran on the rotas and the 20's at superlap - on street tyres (erk)

this is how hot the brakes got WITH THE 20's ON - that's 800*c

so imagine how much hotter they got with next to zero caliper clearance with the 18's

I do think we've been pushing these rims far beyond their intended purpose. It's likely the regular extreme heat has affected them )especially at SL where we were pushing a bit harder/longer) then with the repeated curb hopping (at WP that is) subsequently cracking them. But i am guessing at this stage, like everyone else.

I think you'll find the brakes actually get alot hotter with the street tyres on. With rcomp rubber your braking harder but for shorter periods its the extra long time your on the pedal with street tyres that causes the extra heat.

I just ordered a $7k suspension upgrade today but i am sure it's the wrong set (what would you guys suggest i buy btw?) I've spent about $15k on track tyres in 12 months (several sets of 55's, new slicks, many many sets of 2nd hand slicks as well as new 20" bridgestones and advans recently, all wrong, probably) and $15k again on exhausts, tuning tools, intakes, a few sets of rotors, many more sets of pads, control arm upgrade (all wrong surely). So there's $37k down the drain there. Oh and about $5k on the enkei and rotas too, which we all know about (wrong). So make that $42k thrown away. Oops how about $5k for a stupid active carbon wing (wrong). Make that $47k.

I can't afford the GTR tax on a lot of things. $10k for a set of genuine rotors and pads, how about $2k for some transmission fluid? The GTR tax is.. well, taxing. So we try different things. Some are relatively cheap (and yet better than the more expensive options) and i share the info freely. I don't mind if you think i'm a cheap bastard, no.

be a smart ass all you want, i'd just never buy rota rims. nothing you say will change my opinion.

either gold BBS LMs or white TE37s, my two favorite rims so obviously i'd buy them.

be a smart ass all you want, i'd just never buy rota rims. nothing you say will change my opinion.

either gold BBS LMs or white TE37s, my two favorite rims so obviously i'd buy them.

I really couldnt give a flying fark what you might buy, i just dont care.

But, if anyone can tell me anywhere in sydney (or within 100km) that actually stock these wheels, i will go there tomorrow for a trial fit. I did try to buy these before, it was just too hard. Who stocks them, and in GTR sizes/offsets? I need to sight caliper clearances for myself.

Edited by LSX-438
I've been told that 99% of cast wheels use this material; anyone know?

Don't know about other cast rims. Not many of them disclose the material they use in detail.

I know though that A356.2 is a high tensile version of standard A356.0 which is achieved by a critical tempering process.

The solidification curve during cooling has virtually no margin for error.

It is one of the most common aluminium alloys and is used in aviation framing, car chassis, even missiles.

Yes it is the entry level alloy for structural castings and has more flex capacity than the forged alloys.

I guess it comes down to economics in the end.

I wonder how good the operators and supervisors are in the Rota factory with the solidification process.

Also, given the heat obviously given off on track situations which are bound to arise with this product, I'm surprised Rota don't do any testing with high and low temperatures as well as impact and strain.

I just ordered a $7k suspension upgrade today but i am sure it's the wrong set (what would you guys suggest i buy btw?) I've spent about $15k on track tyres in 12 months (several sets of 55's, new slicks, many many sets of 2nd hand slicks as well as new 20" bridgestones and advans recently, all wrong, probably) and $15k again on exhausts, tuning tools, intakes, a few sets of rotors, many more sets of pads, control arm upgrade (all wrong surely). So there's $37k down the drain there. Oh and about $5k on the enkei and rotas too, which we all know about (wrong). So make that $42k thrown away. Oops how about $5k for a stupid active carbon wing (wrong). Make that $47k.

I can't afford the GTR tax on a lot of things. $10k for a set of genuine rotors and pads, how about $2k for some transmission fluid? The GTR tax is.. well, taxing. So we try different things. Some are relatively cheap (and yet better than the more expensive options) and i share the info freely. I don't mind if you think i'm a cheap bastard, no.

Dude - without people like you most of us wouldn't know shit from shovel. Go ahead and test as many new things as you see fit, some will appreciate feedback, some will bag anything since they are sad, stuff them. You know, how would you like to be the first guy to try Volk's, I'm sure his mates told him he is an idiot too, and look at Volks now.

Wolrd needs pioneers.

I really couldnt give a flying fark what you might buy, i just dont care.

But, if anyone can tell me anywhere in sydney (or within 100km) that actually stock these wheels, i will go there tomorrow for a trial fit. I did try to buy these before, it was just too hard. Who stocks them, and in GTR sizes/offsets? I need to sight caliper clearances for myself.

well clearly you do care otherwise you wouldn't have bothered to write a huge paragraph and even responded to my reply to that.

i hope other gtr owner aren't fks, like you.

Edited by Peter89
Sounds perfectly reasonable.

I'm not suggesting cast is better or even appopriate; but if 99% of cast wheels out there are made from this material, maybe we shouldnt be shooting down Rota (or any other cast rims). I've been using the wrong rims, and pushing them too hard vs their intended purpose. My fault. I'm not prepared to blame the rim automatically, as some people so quickly have. We can learn something here if it doesnt turn into a shitfight, heaps of guys use such rims on the track, i've seen it myself.

I dont buy into the whole cast AND weak tone of some posts. It has far less to do with cast or forged, and so much more to do with rhe design of the rim. A badly designed rim is going to be badly designed whether it is cast of forged.

I am not saying that ROTA are badly designed, however certain designs have stress concentrators in the quest of looking good. Not even castings are equal, and really depends on the quality of the manufacture and the design that dictates the strength of the wheels.

General theme is the better wheels never crack because they buckle to the point you cant get them balanced (wheels off race cars)

Someone else posted at it is not a coincidence that the wheels failed where they did, its likely about the thinnest part of the spoke, its at the outer edge so canti-levered by the loads being transmitted from the wheel to the hub....and the design is based on a design that is forged meaning different mechanical properties. So if these wheels are dimensionally similar to TE37s then perhaps they simply dont have the extra material to compensate for the more material flaws/properties arising from casting and not being forged.

So i blame the copying of anothers design rather then ROTA being cheap or nasty. If they are being sold then they obviously meet the required standards, just not up to the loads of racing whish is no criticism.

...and hats off to the poster for posting up the findings. Would have been easy and understandable if you have of kept the failures to yourself. So, thanks for sharing

I dont buy into the whole cast AND weak tone of some posts. It has far less to do with cast or forged, and so much more to do with rhe design of the rim. A badly designed rim is going to be badly designed whether it is cast of forged.

I am not saying that ROTA are badly designed, however certain designs have stress concentrators in the quest of looking good. Not even castings are equal, and really depends on the quality of the manufacture and the design that dictates the strength of the wheels.

General theme is the better wheels never crack because they buckle to the point you cant get them balanced (wheels off race cars)

Someone else posted at it is not a coincidence that the wheels failed where they did, its likely about the thinnest part of the spoke, its at the outer edge so canti-levered by the loads being transmitted from the wheel to the hub....and the design is based on a design that is forged meaning different mechanical properties. So if these wheels are dimensionally similar to TE37s then perhaps they simply dont have the extra material to compensate for the more material flaws/properties arising from casting and not being forged.

So i blame the copying of anothers design rather then ROTA being cheap or nasty. If they are being sold then they obviously meet the required standards, just not up to the loads of racing whish is no criticism.

...and hats off to the poster for posting up the findings. Would have been easy and understandable if you have of kept the failures to yourself. So, thanks for sharing

To be frank Roy it's totally over my head. I am not a metalurgist nor engineer. I'll leave it to the eggspurts to pontificate :banana:

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