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


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thanks Dunc/Martin.

will get confirmation from the yanks about a few things but might give their wheels a go once I confirm specs/prices.

are you producing those front splitters yet Martin? would be keen to get one if you were happy they did the job.

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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?

Ohh so that's why you weren't racing yesterday at WP :) Was excited to see your car out after superlap, but i didn't know it had issues (i got there late). Hope everythings alright!

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?

hmm interesting, keen to see some pics of this.

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..

DSC_0518edited.jpg

DSC_0520edited.jpg

DSC_0543edited.jpg

This is pretty weird, cracked like this on both front wheels (on a single spoke each side)

Pics below. Keep in mind these rims have had a hard life (essentially only used on track, on a 1700kg car, with slicks).

yes, but it was also a very short life. 6 months?

at least you got away without any damage from it!

thanks for the pics mate,

ive seen this on VOLK racing rims as well so other factors could've contributed to it.

How are the back wheels holding up?

After this issue, will you buy another set from ROTA?

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?

Its cracked where i would have expected. this part of the rim has the smallest cross sectional area and therefore the highest stress. I have been reading this thread from the start as there are a lot of rota hating people. (im not 1)

Out of 4 rims you have (professionally) tested and 1 has failed. It a very small sample size and not conclusive at this point. Have you spoken to the manufacturer? they maybe interested in the research effort you have put in. If i was the owner/manufacturer of rota i would be, i would also be supplying you new wheels (to test) for free.

thanks for the pics mate,

ive seen this on VOLK racing rims as well so other factors could've contributed to it.

How are the back wheels holding up?

After this issue, will you buy another set from ROTA?

which volk racing rims? forged or cast? would love to see pics of that.

personally i've never seen this kind of thing happen with a TE37.....

I have to say I'm not surprised to see the rota cracked. they are a cheap wheel built to a price. for the money they are good value but in no way are they are high quality top strength wheel. I certainly wouldn't head out on track with them. I've certainly never had it happen with any BBS wheels I've run on various race cars either...

Its cracked where i would have expected. this part of the rim has the smallest cross sectional area and therefore the highest stress. I have been reading this thread from the start as there are a lot of rota hating people. (im not 1)

Out of 4 rims you have (professionally) tested and 1 has failed. It a very small sample size and not conclusive at this point. Have you spoken to the manufacturer? they maybe interested in the research effort you have put in. If i was the owner/manufacturer of rota i would be, i would also be supplying you new wheels (to test) for free.

quote = .. after a session at WP i noticed both of the front rims have a spoke which is cracked all the way through.

Its cracked where i would have expected. this part of the rim has the smallest cross sectional area and therefore the highest stress. I have been reading this thread from the start as there are a lot of rota hating people. (im not 1)

Out of 4 rims you have (professionally) tested and 1 has failed. It a very small sample size and not conclusive at this point. Have you spoken to the manufacturer? they maybe interested in the research effort you have put in. If i was the owner/manufacturer of rota i would be, i would also be supplying you new wheels (to test) for free.

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.

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.

Or a flying pig, but you'd have though that Xrays would have shown up either if these issues if they were there...

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.

It will fail on the weakest link, failing due to water is still due to weak casting, if what happened to you happened to every other rim manufacturer then there would be thousands of damaged rims.

But I am glade that you are the guinea pig for the use of these rims in motorsports. Shit like this should not be tolerated, your playing with your life.

Or a flying pig, but you'd have though that Xrays would have shown up either if these issues if they were there...

Exactly. Some people chime in without even reading the thread. It's not a dodgy cast issue.

The xrays have been posted.

Edited by LSX-438

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