LSX-438

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've been told that 99% of cast wheels use this material; anyone know?

TwoCents and Intensevil, thankyou for your sensible contribution, even if you're not on the money it gets you thinking. Edit: i think the load for each of those rims is 630kg, but i would need to check.

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.

it's just the facts. i am trying to present a balanced view. over the years i've had plenty of stuff break at the track, and seen a lot more besides. let's just have the good grace and maturity to realise that. i respect your view. you've made it well aware to all.

I dont think anyone is debating the strength of a cast vs forged wheel and/or what happens to them when you drive offroad or smash them around.

Some here: http://www.koryleungphotography.com.au/gal...CRD5/index.html

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.

Perhaps you are right on that one. My mistake perhaps. We did try (and had them xrayed).

Guys PLEASE let me do my homework before you slander a forum sponsor. I've posted this info so others an see a potential outcome of running such rims on a 1700kg car, with slicks, running say 1:02's around wakefield, with 1mm caliper clearance. I believe these wheels have taken a lot of punishment and extreme heat (here are my brembo's after superlap for reference) it's possible/likely i have pushed these wheels beyond their intended purpose to be frank.

hmm, same story really, we just dont know the story behind any of those. I'll try and get some testing done of my rims, hopefully it will shed some light. It's very easy to assume they are shithouse quality, but a lot harder to prove anything either way. I have smashed these up ripple strips hundreds of times, perhaps the load with slicks on a 1700kg car in combination with the abuse was just asking too much. I dunno. Give me some time guys.

You might be right guys, might be wrong too. Could be a little from columns a and b. Most of those smashed wheel pics are probably on relatively lightweight cars running street tyres on the street. Perhaps some of the accidents are a result of a failed rim, or perhaps results of accidents/smashing up gutters etc. Does anyone actually know the stories behind any of those pics? If you do, please tell. Otherwise we're all pissing in the wind.

I really had reservations about posting the pics of the cracks up, because of the usual "told you so" trolls who put zero research into anything (beyond google). It would have been easier to not post this. I am sure i could find dozens of smashed rim pics (of other brands) too using google. I would rather people understand there is a questionmark in my mind however there could be a reasonable explanation. Perhaps we can find out what the PROBLEM is/was and make conclusions afterwards. It's not like these rims cracked on their first outing, they've done a lot of laps and have copped decent abuse. I am really perplexed how/why to rims would crack like this in almost the same way, on the same day and same track session. It's almost too coincidental. On the positive thinking side i would say it's driving through water on super heated rims; on the possible negative side perhaps the material was weak and/or fatigued.

seen a few of those racked/smashed pics before, which is why we had them xrayed. so whats going on? anyone with useful info?

jeez dunno how many times that pic has been posted great research by the looks of it, both wheels have been in some form of accident. ffs.

Exactly. Some people chime in without even reading the thread. It's not a dodgy cast issue. The xrays have been posted.

Just to clarify, BOTH fronts failed at the same time. I will try and catch rota this week. They should probably looks at the rims for their own reaearch anyway, which i will gladly give them; i dont expect these to be covered under warranty but would like to know their assessment on what happened.

http://www.trackchat.com.au/forum/showthre...ght=nurburgring http://www.trackchat.com.au/forum/showthre...ght=nurburgring

Back wheels look fine. There was a lot of water around the pits at the time, possibly i drove through some water with very hot wheels? That would explain why it's two spokes on each side perhaps. It's just too coincidental. The more i think about it, the more this makes sense. You've seen it woth VOLKS as well?

Very true!

interesting stuff, nice work Martin. Do you think the new tyres would have a similar proportional gain with stocker suspension?

Congrats guys, heaps of PB's all round yesterday. Very lucky with the weather again too, it was sensational. I had wheel issues (cracked two rims) so my day was cut short at 11am unfortunately. Relaxed and watched the action instead. Who's in for the next round there in two weeks?

Pics below. Keep in mind these rims have had a hard life (essentially only used on track, on a 1700kg car, with slicks). Also the clearance between the calipers and wheel is extremely limited, which i think contributes to the heat these things go through. some of you may have seen my rotors at superlap glowing.. Also i had a word to some other people yesterday that mention they have seen this sort of thing with other rims. Let's not automatically assume there is a problem with the rim; there are a lot of variables. Anyway it raises a big question in my mind at least.. This is pretty weird, cracked like this on both front wheels (on a single spoke each side)

Hey guys, just a quick (yet important) update for these ROTA rims.... I have done perhaps 40+ sprint sessions on these at OP, WP and EC. As you may know we had the cast xrayed (results were ok) and they seemed to hold up fine until yesterday... after a session at WP i noticed both of the front rims have a spoke which is cracked all the way through. Suffice to say my day was over. Lucky we picked it up when we did. I am a bit perplexed as to why/how both rims could crack in identical ways on the same session. I will post up thoughts and pics as we try and work out what happened. Given the extremely tight clearance and high heat, and massive load with the slicks, perhaps the material became stressed/weakened over time. I was bouncing over kerbs ysterday so i think that contributed to them finally cracking. I think we'll revert to the enkei's for next round. I am unsure if this is just a "normal" wear and tear thing or otherwise. Does anyone know how often race teams replace wheels?

Any update on this Martin (the new JRZ setup)? Also anyone tried other coilovers, kw? tein?