The 255’s are a smaller OD and will affect gearing for folks. The load rating is also noticeably higher on the 245’s
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The 255’s are a smaller OD and will affect gearing for folks. The load rating is also noticeably higher on the 245’s
Nobody has committed to anything yet. The test group can go that way if they want. I don't think the data is quite as good but it might be sufficient. At least good enough to see if more testing is warranted. Costs more for the test participants but they would get to race with the rest of the group.
Richard P.
I could go either way I suppose. If we're actually racing I think it'll be a better test in the heat of battle.
So the 245/45/17 Azenis is nearly the same OD as the 275/40/17 RRs. The 255/40/17 Azenis is wider than the 245 (obviously), should be better for wear and heat. The 255 Azenis is 0.6" smaller in OD (25.6" OD for the RR, 25" for the 255 Azenis). The price difference for the 255/245 Azenis is less than $1 on tire rack. These tires are in the $150 range - tires at this price would substantially change my ability to show up to races and prepare the car.
255: https://www.tirerack.com/tires/tires...omCompare1=yes
245: https://www.tirerack.com/tires/tires...omCompare1=yes
- Josh
According to the Falken tire website, the 245 isn't good for the width of the wheels we run. http://www.falkentire.com/tires/pass...is-rt615k-tire
245 = 7.5-9.0"
255 = 8.5-10.0"
275 = 9.0-11.0"
There are a lot of 9.5" wide wheels in the CMC field.
Additionally, right now big black doughnuts are a common and minor form of damage on the sides of our bodywork. At some point, wheel contact would cause more damage to both cars. Not the best money saving option.
Richard P.
In miataland 225's on 15x9 is very common and works quite well, the wider wheel helps the tire work better. I wouldn't worry about that, the donuts on the other hand are an interesting point indeed!
2 cents from the past and now outside....
There were several reasons that I stopped racing, some race-related and some not. However, the RR tire issue was a big factor for leaving and remains an issue that would have to be resolved before I return. The issues of cost, build quality (mostly the threat of tread seam separation), performance drop-off and Toyo contingency parity seem to reflect what a lot of others have already stated.
I believe that Nitto is still part of the Toyo family. The Nitto NT01 is a very good tire with a lower performance capacity but with better lifetime consistency, a lot like the old RA1. With that in mind, does anyone think that Toyo would be interested in having the Nitto NT01 as the CMC tire the Toyo RR as the AI tire? This would better match the cost factors of the two series and allow Toyo to put the Nitto name out there a bit more. The risk there is that Toyo will just crank the pricing up on the NT01 due to being a race specific tire.
UTGR treadwear numbers are not exactly reliable performance indicators. The treadwear number that is generated in controlled tests is the highest number that the tire manufacturer can put on the tire. The manufacturer can choose to advertise a 200 TW tire as a 140 TW tire if they choose to do so to market the tire as a high-performance model. They cannot say that a 140 TW tire is a 200TW tire.
Contingency programs that award heavily to the top finishers need to be evaluated, especially with a tire that is considerably faster as a sticker tire. Aaron McSpadden capitalized on this when he ran CMC and was able to have fresh tires at every session that he wanted. I will give kudos to Aaron for having a good set-up and reliable car as well as high driving skills. I don't think the top contingency prize should be able to fully fund an entire tire budget.
Currently, if I was to get my CMC car out of storage, I would buy a set of NT01's and run a variety of different events on different tracks with a variety of groups.
Oh, and man do I miss TWS!
Rob Liebbe
Is it currently, though? I've run the NT01 before. It was fine but I didn't do a detailed comparison of performance from old to new. The bigger question is whether the NT01 you can buy now is the same that you ran before? The RA1 went through at least three iterations while we were running it (I'm guessing more) even though Toyo denied it. The current RR is different than the RR we started on. The common end of life for RR's when we started was a light cording of the outside edge all the way around the tire. It was guaranteed if you didn't flip the tire on the rim after the first event even though the tread seemed to be wearing evenly otherwise. I haven't seen an RR cord like that in a couple of years even when we don't flip them. What else have they changed???
Richard P.
At this point my vote would be for the 275, mostly to make it easier to get buy in from the rest of the group. It has almost the exact same specs as the current tire on OD, load rating, section width, weight, etc. It would be a direct bolt on and wouldn't require gearing or track width changes. It costs a bit more than the smaller sizes but it's still $300 cheaper than a set of RR's and our testing will show being competitive after two events or we won't go this route.
Richard P.
This is the reason I bring this tire issue up every year (Daniel beat me to it this year). I hate to lose great racers like Rob due to tire cost. I know others that stopped racing because of tire issues. Some have sold their cars. I always thought of CMC as the class that would let a working man road race. If you have to purchase a new set of tires for every event (and you do if you want to be as fast as possible for every qual and every race) we will lose racers and keep others from joining us in the first place. Look at The Drivers Edge. They sell out every event. If we can make racing in CMC cost near what it cost to run the Drivers Edge our numbers will go up. I think if we can pull off getting a tire that we can run three race weekends (two sets for a regular season) that cost $300.00 less then the RR we could build up to twenty car fields in a few years. I could be wrong but as you can read here tire cost does run people off from CMC road racing.
JJ
We should probably decide by Friday, lots of good points made, does anyone else have thoughts here? IMO the 245 is the perfect combo of OD size vs value vs load rating, 17x9.5 won't be an issue, if the tire doesn't extend past the wheel though it may result in wheel contact vs tire contact. 275 may be good for damage insurance :-/
I am just a prospect (sorta like Sons of Anarchy lol). I have loosely followed CMC for several years while I been overseas. I can tell you the tire costs certainly made it hard for me to go the CMC route. I thought hard about spec miata simply because the tires and other consumables probably cost half what it does in CMC. I knew I wanted to road race, and I knew I loved American Thunder V8s, but I'd probably be happy in spec miata too and the costs are less.
As I got more serious and closer to coming back stateside I was still on the fence for about a year trying to decide which way to go. The only reason I pulled the trigger on an built CMC car is because 1. I got a hella good deal on hopefully a great car AND 2. The car came with 5 complete sets of 16" RA1 tires for me to train on. At the current moment, I need some 17" wheel solutions, and I cannot afford a set of RRs even if I spread two sets over 4 events I can't afford that. But I pulled the trigger anyways because in a year from now I hope to be in a little better financial situation to afford to upgrade to 17's and run RRs. But...........
But damn, Im a newbie here, and hearing all this about how the RRs fall off so drastically before they are worn out, thats bullshit. That'll run me in the other direction in a heartbeat!! Years ago it was just the RA1 (which is just as expensive now)......but what happened? How did we end up here with RRs? Did the whole CMC community cast their votes for RRs? Supply problems? Or was NASA and Toyo suck starting this blow torch pushing some agenda?
The fact that a revolt is in the air gives me some peace that maybe by the time I have my competition license next year, as a class, we will have this resolved.
It probably costs less to run a Miata but more to be in the top half of the field in a Miata. They run the same tires we do and replace them just as much or more than we do. It's way cheaper and easier to be a race winner in our class. And we're much cooler to hang out with... :-)
Tires for our class are mandated by NASA in conjunction with Toyo and their sponsorship contract. We were on RA1's, then R888 (which went poorly), then back on RA1's and then RR's.
Toyo is a business trying to make money by selling tires. Selling more race tires helps the money part of their racing program. The advertising from the NASA program is supposed to help them sell more street tires. We don't have any information on how the numbers work out. It's completely possible that even with the current setup, the racing side of the house loses money and is considered part of Toyo's advertising budget. Or not???
On the other side, NASA is a business trying to make money. They get money from Toyo for the tire program. From the tire program, NASA gets to entice racers with the promise of big money payouts (in the form of tire coupons) for winning. The more racers that sign up to race, the more money they make. If everyone is happy with the tire situation, it's a big win for NASA. If people aren't happy with the tire situation, people don't sign up. The big question (that's almost impossible to answer even if we had access to the numbers, which we don't) is at what point do the losses from people going away because of tires exceed the net benefit from the money coming in from the tire contract?
First, it is pretty unlikely this will be resolved before you get your license. The tire contract is big money (we believe) and is probably signed for multiple years. It will be really challenging to "officially" change the tire rules. Whether we as a local group decide to do something different is maybe another question? On the other hand, there is some hope. Management isn't completely blind to what is going on. Locally, they have instituted a street tire subclass to the TT groups. If that goes well, it will help our cause. TT isn't a spec Toyo class and isn't covered by the big Toyo contract so this was easier to experiment with there.
Also, a bit of perspective is in order. If the tire degradation issue realistically affects your competitiveness within, say, the next two years, you will be considered to be extraordinary. We are all hoping that you are extraordinary cause it's great to have more racers fighting for the pointy end. We will also do whatever help you to get to the pointy end. Even if you don't get there that quickly, we will make sure you have a good time trying. There is really good racing going on even if you aren't on the top of the podium. The amount to learn between where you are now and the pointy end is staggering. Get ready to drink from a fire hose. And have a blast doing it. Don't worry, it's a lot of fun but not addicting. You will be able to stop whenever you want. Probably...
Richard P.
I have no illusions of being a podium finisher for a couple years. Looking forward to the mentorship. And thanks for the historical and background info regarding the business end of the tire debacle.Quote:
Also, a bit of perspective is in order. If the tire degradation issue realistically affects your competitiveness within, say, the next two years, you will be considered to be extraordinary. We are all hoping that you are extraordinary cause it's great to have more racers fighting for the pointy end. We will also do whatever help you to get to the pointy end. Even if you don't get there that quickly, we will make sure you have a good time trying. There is really good racing going on even if you aren't on the top of the podium. The amount to learn between where you are now and the pointy end is staggering. Get ready to drink from a fire hose. And have a blast doing it. Don't worry, it's a lot of fun but not addicting. You will be able to stop whenever you want. Probably...
I like the idea of running a 245 tire from a cost perspective. For this test though, I think it makes sense to stick with the 275 to minimize the number of variables at play and give these tires the best chance at success.
My vote is 275 for this test. I'm ready to order.
- Josh
Fair enough I’m good with 275s
The next big question is whether the testers are racing or TTing as part of the experiment? Signing up for TT would mean purchasing Azenis and Toyos and signing up for racing and supersizing to TT. Sounds expensive. Doing the test as part of racing has its drawbacks but costs less...
Richard P.
Could go both ways, supersizing allows them to run both but costs way more (kind of a necessity when you're a guinea pig for a change) which makes it ever more important to capture as much data as possible. It's proof of concept but again more expensive and the data may not be perfect if they end up chasing some POS BMW that won't let them by and heat their tires properly throughout the session. Furthermore (imo) we cannot base jack or shit on an event that happens in the cool of March. I personally believe we need to compare data, cycle for cycle, of the performance of the RR vs the 615 while being run 100% lap for lap to produce any real output for us as racers to even consider defecting from the RR. If I sound like a defender of the RR, well, there are political considerations, but aside from that here in RM the top 3 are not observing the significance of dropoff in times so I personally believe I should pitch this nationally to see where everyone else stands and perhaps all regions should collect lap times vs RR cycles to really get a feel for what's going on and if there is a true need for a change.
I prefer to race, AIX or fun-run. I think we'll get better data in a battle rather than TT.
I'll have at least 8 sessions with data on my Azenis before Cresson, maybe more. If we don't want to race I'll have to think about TTing, and race on year old RRs from Cresson last year! I bet they'll be faster than a fresh set.
- Josh
Here's the best price I found on 275/40-17 Azenis right now. $690 for 4 before tax, screaming deal IMO.
https://www.ebay.com/itm/311851348770
Mine are ordered, Dan's are ordered. I'm looking forward to Cresson!
- Josh
I think it'd be worth some time to develop an actual test protocol. The goal is to validate number of sessions before grip degradation. That to me would best be done by having a pair of highly consistent drivers doing back to back runs on brand new unshaved tires, brand new 2/32s tires, and something like 8 and 12 heat cycle tires that started life unshaved. Obviously the driver should not be allowed to know which set they are driving on.
We used a back to back in one session test like that to validate the grip impact of 225s back in the day when we were trying to figure out how to slow down the S197s.
I talked with Jerry and we are willing to help out the group and be the test drivers.
Some of this is funny to me as how involved the test has to be. Funny because in my mind I want to think we did a huge (sarcasm) tire test during the 888 debacle I think with Proctor doing back to back sessions on different tires and then the determination was made. Seems similar to the way I remember some rules being changed based upon one race at ECR with data only comparing two cars. Yet now we have to have a Nascar level tire test?
We don't have to...we could just shoot from the hip.
We can actually make this happen.
As far as I know, Josh is running in a set of sticker RT615K+ at MSRH this weekend and will have those with him at MSRC. I'm bringing a set of sticker RT615K+ to MSRC with me and plan to use them for a portion of the friday test and saturday warm-up and TT sessions.
We could make Josh put on a blindfold and 'change' his tires friday and have him go run a session, then come back and we'll 'change' his tires again and not tell him what we're putting on. IE -- may not have put stickers on etc. Would be close to a blind eval and I think he is consistent enough to make it a reasonably successful test and it won't be his first session ever on those tires.
Also -- in line with my original proposal, I will run them in friday practice (4 sessions-ish), saturday warmup, sunday warmup, and then maybe we'll do an AIX Race 4 Sunday for the street tire cars to evaluate how the tires 'race' to be sensitive to the other potential issues that are out there.
Personally I would think we'd want to spend a bit of time simply driving on these (and building heat cycles) and optimizing setup before thinking we're ready for a test. I would be surprised if we did not find that they require different alignment, pressures, and spring/damper settings to work well.
Lots of discussion going on, glad to see that. Ideas are all over the map, at least we're having the talk!
The weather this weekend isn't looking great, so I'll at least get to text azenis as rain tires :)
Got em mounted, I'm wondering if they'll rub more than the RRs.
Attachment 1872
- Josh
People talk about the R888 debacle. What went wrong there? 615's vs R888 vs R888r? Prices are about the same on Tirerack. Curious to know why everyone dislikes the R888?
The R888 when we were running it got greasy if you pushed it too hard. It wasn't fun to drive or race. It was said that it needed a more sophisticated driver to extract it's full performance. The AI/CMC group gave a big middle finger to that...
I would guess the compound has been revised since then, especially in the newer R888R???
Richard P.
I'm not planning doing any tests with shaved tires. Just write the rule to not allow shaving. If it's possible to gain a performance advantage by paying extra to turn the tires into one weekend or one day tires by shaving them, then there is no point in switching tires.
If someone else wants to spend the money on shaved tires to test, I would be interested in the data. But, that same money spent to add to the sample size of the regular tire test would be much more useful.
Richard P.
What is the tread depth of the tire Josh and Dan are going to test?
Jerry
I haven't measured them yet. Starting at full tread. Measuring will certainly be part of the testing. Also part of the test is to see if they can handle full abuse at full tread depth without chunking. Most street tires can't but these have very large tread blocks and I haven't heard of people having problems with them even though most people are using them as track tires.
Richard P.
Since we don't appear to be doing a full tire test at Cresson, Josh had to buy a set of Toyo's to race on. That, combined with the test tires, fixing his brakes from the last race, and the general costs of running events in back to back weekends has Josh running a bit thin. Last I heard he wasn't planning to do the Friday test day or TT sessions.
Richard P.
All that setup work (specific to Josh's car, anyway) is planned for this weekend. That's assuming the weather plays nice. The forecast is all over the map and changing every time I look. If the weather holds out, we will have a full weekend of setup and heat cycles on his tires with the stickers still on mine. If the skies open up, Josh's won't have as many effective cycles on them and mine won't be stickers anymore...
Richard P.
Where has anyone been able to buy a set of RR’s from? I haven’t bought a set since middle of last year and can’t find anyone that has any in stock to ship to a residence.