Spoke with an Avon Tire Engineer Today

[Claviger]

So after a long chat with tech support, I started getting to questions he didn't know the answers to. Surprisingly he gave me the extension for one of the actual engineers :0

We spoke for awhile about the demands of the Rocket specifically on tires. I finally got a DEFINITIVE answer about Cobras, here it is:

ALL Cobras are dual compound, medium center, soft shoulders with one exception. The gold wing fitment is a dual exterior compound with a third compound underlying the medium and soft to help heat dissipation and treadwear.

So there it is, the Cobra IS a dual compound which explains how it has the best corner grip and better mileage than the Metzler.

 

[1olbull]

Nice work, Rob!
My problema is the aspect ratio is just 50, providing a smaller radius and less lean angle than does the 55 aspect of the Exedra Max.

 

[Claviger]

Totally agree man, it's unfortunate there's no 55 aspect Avon.

Some other tid bits she dropped:
The Cobra isn't going to be phased out in the foreseeable future..
When and if they do decide to do so, the 240/50R16 will be included in the new line up, it sells well enough to maintain in the fitment inventory.

 

[1olbull]

@Claviger
On a side note my TPS has finally just shipped . . .

 

[Claviger]

NICE!

 

[barbagris]

ALL Cobras are dual compound, medium center, soft shoulders with one exception. The gold wing fitment is a dual exterior compound with a third compound underlying the medium and soft to help heat dissipation and treadwear.

So there it is, the Cobra IS a dual compound which explains how it has the best corner grip and better mileage than the Metzler.

Also explains why Rockets can shred them in warmer climes.

 

[1olbull]

Also explains why Rockets can shred them in warmer climes.

Especially usuns on "heavy" Rockets!

 

[barbagris]

Interesting though. I'd say in COLD weather the Metz out corners a Cobra. I've ridden on ice on 880's with no issue (other than flapping sphincter). The German lads say that up North the Metz is a better bet - whereas South where it is much warmer the Avon is favoured. Only used a front Cobra and it lasted less than the ME880. Heard from an Austrian Metz dealer that the 880 is really designed as an H rated tyre - but it withstood the V test. They warm up fast but don't shed heat. This (so far) seems to be THE BIG PLUS with the Emax. It warms up fairly fast - but sheds heat fast too.

 

[Claviger]

I agree on all accounts in the cold barbagris. In the sub 40f temps early in the morning, even when dry out, I have to be a bit ginger anywhere over 4000 RPM or it'll spin up. Once it warms to the 50f range, sticky and great, but those slightly above freezing temps have the rear tire struggling. I mentioned that on the phone and she acknowledged it as something she'd heard before.

Wish I'd recorded the convo to post here :/

The bit about the 880 being a true H rate and not V in design, but withstanding V, sounds credible. Sounds like a good result from over-engineering a product lol, something R3 owners may know something about lol.

My 880 front had plenty of depth left when I took it off, it was cupped bad. Bull's comment has me wondering about weight a bit, I've cut something like 75lb off my R3, still need to get it weighed.

The Excedra Max is definitely a great alternative to have and I hope it sticks around for years to come, I'm planning on trying one out next

 

[barbagris]

The Austrian dealer seemed to know his stuff. He was a 3rd Generation tyre guy and their family has tight connections to Metz. I boiled the oil out of my ME880's front an rear - they went blue - the rubber was balling off then basically turned to powder. At the time there was some "panic" about some rear Cobras blowing out (In OZ iirc) so I went Cobra Front and Darkside rear. Eventually moved to Emax rear which so far is resisting and use a rear tyre reverse mounted up front. Originally the Avon Azarro (discontinued) now a Bridgestone. So Far So Good.

What is an issue here is HIGH ambient temps. In summer easily hits 40° to 60° Celcius at tarmac level. Has to be similar in alot of OZ and southern US. This is already above the design operating heat for most road tyres - Track tyres run hotter. I have heard that many road tyres have design operating temps of 35°C-ish. I ran temp gauges for a while and was hitting high 40's C at ambient 25°. They'd hit that within 5kms of riding from shade - took upto an hour to cool down. With the D/S took 10kms to warm up - dropped within 10mins. Ruddy gauges (TPMS) stopped working so I've never done teh EMAX.

The ME880 I had was most definitely a pinch fit - I did see a chart from Metzler USA that suggested it was not designed for a 3.5" rim - actually more for a 3.75 (range 3.5 to 4). I measured mine and it was (fitted) 143mm wide with 90 aspect. The Cobra was 150wide and 80 aspect. Read into that what you will- bit it explains some of the cupping.

My tyre place is 3rd generation. They do tyres - only tyres. The old man took one look at the R3 and said - "What idiot specc'd V rated rubber for that? - Run Z rated in the Spanish summer or expect less than half the expected mileage". His son - now boss - is a biker and has searched high and low for alternatives. It why I am pondering a 17" rim conversion on the spare rear wheel. Z rated rubber.