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

[magic1]

apologies, 2 rims..

[Deano45]

Your in denial, these rims are less than half year old, normal rims wouldn't do that, that looks to be very weak casting, there might be a million air bubbles in those rims.

Duncan had these rims x-rayed after the first time that he used them at the track.

He runs full michelin slicks from the Posrche Cup on these rims and does a lot of racing and test days on them. Combined with a 1700KG car, that is a lot of stress on the wheels.

It is interesting that only 1 spoke has broken on each of the front wheels.

Duncan, are you going to get them X-rayed again to see if any cracks are developing in the other spokes?

I would like to hear what you information you get back from Rota about this.

From memory, Duncan got these as he couldn't get the TE37's in the correct offsets or size at the time for the P-cup slicks (Correct me if I am wrong).

[2lazy]

Duncan had these rims x-rayed after the first time that he used them at the track.

He runs full michelin slicks from the Posrche Cup on these rims and does a lot of racing and test days on them. Combined with a 1700KG car, that is a lot of stress on the wheels.

Dont care, you can't put a price on a human being.

This was due to an accident, its rota with a work sticker, I have never seen a rim involved in an accident crack like this.

Spot the difference?

[LSX-438]

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.

Dont care, you can't put a price on a human being.

This was due to an accident, its rota with a work sticker, I have never seen a rim involved in an accident crack like this.

Spot the difference?

[dori34]

You can't compare te37s to this wheel as they're both made differently and from different materials. compare with other cast made wheels, such as work emotions etc. i'll get pics up soon of the crack on the volk racing wheels. they were an earlier model- av racing i think.

I'm too interested to see what ROTA have to say about this as i'm about to get a set from fatz group buy. Where are the pics of the xray that was done as i can't see it on my mobile browser.

[2lazy]

You want more

http://www.clublexus.com/forums/attachment...broken-rota.jpg

http://img114.imageshack.us/img114/4254/dsc52797kp.jpg

http://lh4.ggpht.com/gnatster/SP-itHDg2-I/...eel%20Spilt.jpg

http://img67.imageshack.us/img67/424/img1420ai8.jpg

http://media.photobucket.com/image/cracked...26/img_1049.jpg

http://i649.photobucket.com/albums/uu217/j....jpg?1275874688

and guess what? your one of them.

[CaBS]

xray scans of the rota rims, after one track day:

http://www.forrestfamily.com.au/duncan/GTR...rota_xray_1.JPG

http://www.forrestfamily.com.au/duncan/GTR...rota_xray_0.JPG

apparently the cast is perfect.

Here =)

[LSX-438]

seen a few of those racked/smashed pics before, which is why we had them xrayed.

so whats going on? anyone with useful info?

Edited June 7, 2010 by LSX-438

[handbrake]

I'd hate for this to turn in to a 'I told you so' shit fight.

Duncan has kindly provided plenty of detail in trialling many motorsport parts. Feedback like this is valuable to everyone in the SAU community. If people limited feedback to only positive outcomes then appropriate decisions would be difficult to arrive at. He went to what I would think were acceptable lengths to scrutinize the rim's quality.

I hope the answer lies in using forged rims as this is the path I have taken with the CCW C10, though at more than three times the price of the rota rims mind you. The 10 spoke pattern of mine has rather thin spokes so I hope they hold up to track use with the slicks.

Thanks for the honest feedback Dunc. Keep the lap records coming.

[LSX-438]

I'd hate for this to turn in to a 'I told you so' shit fight.

Duncan has kindly provided plenty of detail in trialling many motorsport parts. Feedback like this is valuable to everyone in the SAU community. If people limited feedback to only positive outcomes then appropriate decisions would be difficult to arrive at. He went to what I would think were acceptable lengths to scrutinize the rim's quality.

I hope the answer lies in using forged rims as this is the path I have taken, though at more than three times the price of the rota rims mind you. The 10 spoke pattern of mine has rather thin spokes so I hope they hold up to track use with the slicks.

Thanks for the honest feedback Dunc. Keep the lap records coming.

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.

Edited June 7, 2010 by LSX-438

[Beer Baron]

they are a comparatively low quality cast wheel. most likely the quality of the powdered metal they use and the make up of that alloy is not good. it may not be entirely suitable for the purpose. apart from the casting process the make-up of the material used is pretty important. the fact is you don't have to search too hard to find stories and pics of these type of wheels that have failed without any mis-use or accident. I can't think of one incident I've even heard of a TE37 of the like failing without a BIG accident to go with it. even the cast volk wheels and the other japanese high pressure cast (aka semi-forged) wheels seem to last very well.

like I said they are built to a price and as with lots of things in life you pretty much get what you pay for. for the money they are not a bad wheel but personally for track use I'd go with something forged or at the least a japanese made high pressure cast wheel. with the weight on them and the forces they are subjected too they need to be strong.

for a basic street car I wouldn't have a problem using the rota wheels or any of the other similar brands that make wheels 'inspired' by other brands designs.

at least you paid attention and caught the failure before you had your car damaged or even worse were injured.

[dori34]

Any xrays after the cracks? have you contacted the rota distributor and sponsor on this forum to see if they have any input to why it may have cracked?

[2lazy]

All rims can crack and buckle.

All rims do have a used by date, especialy in motorsports.

The type of material alloy used determines the rims strenght.

Froget casting are generally stronger than any form of casting.

Gravity, low pressure and spun rim casting all have their pro's and con's.

So why do rota's have such a bad rep? first there was a company that stopped selling these rims due to a death of one of their customers, then its that they are new and fail, and how they break, seeing that there arent any air bubbles the only conclusion I can come up with is the type of alloy used, if they are using used metal which is very common in china, you have a huge range of alloys melted so it would be impossible to determine the rims strengh, if the thing could that they are using cheaper grade alloy.

[LSX-438]

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.

Edited June 7, 2010 by LSX-438

[CaBS]

Here is another xray showing a large crack.

[2lazy]

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.

Maybe this will make you feel a bit better.

http://www.nissansilvia.com/forums/index.p...p;#entry5597815

[CaBS]

Maybe this will make you feel a bit better.

http://www.nissansilvia.com/forums/index.p...p;#entry5597815

Lazy how does that even respond to what LSX-438 posted? Without any background information they are about as useful as my "large crack xray" pic i just posted. Infact probably less useful cause they dont even raise a smile.

I can see your response now in my crystal ball. Its a picture off google images of a random smashed rota with no background info as "evidence". =D

[LSX-438]

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.

[nfi]

Duncan, I feel for you. Appreciate you posting this up and the research you have gone into fairly (not internet propaganda).

I always seem to come back to something someone told me years ago with rims. It comes down to production costs and accounting....

When buying rims you can pick any two of the below:

1. Strong

2. Light

3. Cheap

It would appear its been verified again here. I suspect that the manufacturing costs of producing rims properly (strong & light) and cheaply simply isn't feasible when physics meets margin.

[hrd-hr30]

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.

Are any of the other GTRs out there doing sprints breaking other brands of wheels? If the only wheels breaking are ROTAs, they're shithouse by comparison. If they break because you drove through a puddle, that's really shithouse! If they break because they're on a 1700kg car running slicks and agressively curb hopping... well, plenty of people would have suggested they weren't fit for that purpose from the start...

sorry, I just don't understand the logic of not blaming the wheels for breaking after such a short period of time.

All rims can crack and buckle.

All rims do have a used by date, especialy in motorsports.

that's true, but 6 months and approx 40 sessions (that's only about 8-10 track days) is not a reasonable lifespan IMO.