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sevaun
23-04-10, 08:17
Hi
Out of interest I was checking to see what compounds my Avon slicks are - ie A15 etc.
Can't seem to find any such markings on the tyres. Can anyone tell me how to find out what I'm running?

Sevaun

Bunman
23-04-10, 09:14
Hi
Out of interest I was checking to see what compounds my Avon slicks are - ie A15 etc.
Can't seem to find any such markings on the tyres. Can anyone tell me how to find out what I'm running?

Sevaun


There will be a code number on the sidewall somewhere with normally 4 numbers together.
If you phone BMTR with the number they will tell you what they are.

My code is 2553 A15 Stiff wall. 9.0x20x13

Brib
23-04-10, 09:19
Hi Richard,

No you won't find a compound code as such it's in numbers as Bunman says.

Mine are 9760 7.2/20.0-13 A45 and 12894 9.0/21.0-13 A91

Brian

Craig Powers
23-04-10, 09:29
Hi Richard,

No you won't find a compound code as such it's in numbers as Bunman says.

Mine are 9760 7.2/20.0-13 A45 and 12894 9.0/21.0-13 A89

Brian

Agree with everything said. The 4 digit code is a batch number and only BMTR (or AVON) will be able to help you. I bought new slicks from BMTR this year and BMTR stocked different batches of the same size and compound; all 2010 rubber. They asked me what power and weight the car was, and the fitter was instructed which batch to find based on that. Not sure why.

Common compunds for our cars are A45 front (softest) and A91 (rear). A91 repaced the old A40 & A39 compounds.

The batch number also tells you which way to fit the tyres for direction of rotation.

Craig




loads of batches all of the same compound

sevaun
23-04-10, 13:13
Hi All
Now I understand, thanks for the info:)

Sevaun

BlueGriff
23-04-10, 16:36
The logic of Avonís fitting instruction is a puzzle to me. Canít understand why the direction of rotation is different depending on front or rear wheel drive. Like the compound being hidden in the batch number you do wonder if it is all kept just ever so slightly difficult to find out to maintain a level of mystery. It would be so much easier if they published a list of what sizes are available in what compounds.

Radical
23-04-10, 17:24
http://www.bmtr.co.uk/crossply.htm

PumaWestie
23-04-10, 19:12
Thats just the sizes available. Not all sizes are available in all compounds

yobdab
23-04-10, 19:23
The four or five figure number is not a batch number it is a product code.

Here is a reference list of product code to compounds that I have in my files. Probably not of much help as most are circuit applications.



AVON 7.0 x 21.0-13 treaded 10035 ABC10 A29 compound 7.0 21.0 13
AVON 8.0 x 22.0-13 treaded 10036 ABC10 A29 compound 8.7 22.0 13
AVON 210/550-13 slick 10233 13
Avon 7.0 X 20.0 -13 slick 10990, 10992, 10994 7.2 20.0 13
AVON 8.2 x 22.0-13 slick 10991 A49 compound 8.2 13
AVON 8.2 x 22.0-13 slick 10995 8.2 13
AVON 9.0 x 20.0-13 slick 11212 736 compound 9.0 20 13
AVON 245/60-15 treaded 11244 CR500 A29 compound 245 50 15
AVON 175/530-13 treaded 11438 A24 compound 175 530 13
AVON 7.0 x 21.0-13 slick 11452 A11 compound 7.0 21.0 13
AVON 215/60-15 treaded 11466 A29 compound 215 60 15
AVON 315/660-13 slick 11505 A11 compound 315 / 12.4 660 / 25.9 13
AVON 190/570-13 slick 11521 A24 compound 190 570 13
AVON 180/550-13 slick 11530 A53 compound 180 / 7.0 590 / 21.6 13
AVON 250/570-13 slick 11531 A53 compound 250 / 9.4 570 / 22.4 13
AVON 240/600-13 slick 11620 A53 compound 240 600 16
AVON 265/35-18 treaded 11792 A70 compound 265 35 18
AVON 8.0 x 21.0-13 slick 12186 A53 compound 8.0 21.0 13
AVON 5.0 X 22.0-13 treaded 12381 A31 compound 5.0 22.0 13
AVON 205/580-15 slick 12383 A56 compound 205 580 15
AVON 195/530-13 slick 12419 A53 compound 195 / 7.66 530 /20.8 13
AVON 275/55-15 treaded 13013m A29 compound 276 / 10.9 55 15
AVON 10.5x 23.0-13 slick 2126 A11 compound 10.5 23.0 13
AVON 15.0 x 26-13 slick 2133 A11 compound 15.0 25.0 13
AVON 12.5 x 23.5-15 2351 A11 compound 12.5 23.5 13
AVON 10.0 x 20.0-13 slick 2545 A11 compound 10.0 13
AVON 175/70-15 treaded 5640 A30 compound 70 15
AVON 5.0 x 22.0-13 treaded 5777 ACB9 A24 compound 5.5 21.6 13
AVON 6.5 x 23.0-13 treaded 6136 ABC9 A24 compound 6.5 13
AVON 7.0 x 22.0 -15 treaded 6509 ABC10 A31 compound 7.0 22.0 15
AVON 8.0 X 22.0 - 15 treaded 6587 ABC10 A31 compound 8 22 15
AVON 9.0 x 20.0-13 slick 7210 A11 compound 9.0 13
AVON 5.0 x 22.0-13 treaded 7267 ABC9 A30 compound 5.5 21.6 13
AVON 6.5 x 23.0-13 slick 7290 ABC9 A30 compound 6.7 22.7 13
AVON 9.0 x 22.0-13 slick 7343 A37 compound 9.0 22.0 13
AVON 7.0 x 20.0-13 slick 7390 A24 compound 7.0 20.0 13
AVON 240/570-13 slick 9906 A24 compound 240 570 13
AVON CR6ZZ CR6ZZ - SPECIAL ORDER ONLY
Avon - 8.2 x 22.0 - 13 slick FC/S-2/DSR/CSR - rear tyre 8.2 22.0 13

PumaWestie
23-04-10, 19:27
The number is a batch code as well. Avon can tell yoiu when the tyres were manufactured as well as the compound from it if you ring them and ask

redturner37
23-04-10, 19:57
The logic of Avonís fitting instruction is a puzzle to me. Canít understand why the direction of rotation is different depending on front or rear wheel drive. Like the compound being hidden in the batch number you do wonder if it is all kept just ever so slightly difficult to find out to maintain a level of mystery. It would be so much easier if they published a list of what sizes are available in what compounds. Fitting the tyres the correct way for rotation is probably more important than having the correct compound and you have to know about the construction of tyres to know why. The outer skin of rubber is quite thick when stuck to the casing and some overlap of the rubber is neccesary to avoid butt jointing the rubber. If the tyres are not mounted correctly, forward motion , as we do it could well result in the tread rubber being ripped off the casing.

Radical
23-04-10, 21:05
Fitting the tyres the correct way for rotation is probably more important than having the correct compound and you have to know about the construction of tyres to know why. The outer skin of rubber is quite thick when stuck to the casing and some overlap of the rubber is neccesary to avoid butt jointing the rubber. If the tyres are not mounted correctly, forward motion , as we do it could well result in the tread rubber being ripped off the casing.

However, When I enquired they suggested that it is really only a problem in circuit racing when the constant use can build up the heat, stress etc.

Given the short runs in Hillclimbs or even Sprints it is unlikely to happen.

redturner37
23-04-10, 21:30
However, When I enquired they suggested that it is really only a problem in circuit racing when the constant use can build up the heat, stress etc.

Given the short runs in Hillclimbs or even Sprints it is unlikely to happen. In fairness, circuit racers will never be able to get a car off the line like a sprint hillclimb driver and as far as I am concerned, knowing that the tread could be pulled off is enough incentive to ensure that the tyres are fitted as the manufacturers suggest. They dont put the arrows on for nothing.......

yobdab
23-04-10, 21:47
The number is a batch code as well. Avon can tell yoiu when the tyres were manufactured as well as the compound from it if you ring them and ask

I think you are confusing two numbers. One is a batch code and the other a product code. The product code is the one which is left on the front and right on the rear and is linked to the compound as per the list. Actually Avon call it a Specification Number not a Product Code.

If you study the F3, CF3 and 750MC regs you will see that the four and five figure numbers are quoted as approved tyres. For that to be they must be a constant.

yobdab
23-04-10, 21:50
In fairness, circuit racers will never be able to get a car off the line like a sprint hillclimb driver and as far as I am concerned, knowing that the tread could be pulled off is enough incentive to ensure that the tyres are fitted as the manufacturers suggest. They dont put the arrows on for nothing.......

...............now that is an interesting challenge!

asklepios
23-04-10, 23:40
One of the pleasures of this site is trying to sift opinion from fact.

My opinion is that BMTR and Radical are correct.

My observable fact is the absence of directional arrows on my Avon slicks.

Bunman
23-04-10, 23:59
I think you are confusing two numbers. One is a batch code and the other a product code. The product code is the one which is left on the front and right on the rear and is linked to the compound as per the list. Actually Avon call it a Specification Number not a Product Code.

If you study the F3, CF3 and 750MC regs you will see that the four and five figure numbers are quoted as approved tyres. For that to be they must be a constant.



I agree the numbers are a product code, as I said earlier my 9.0x20x13 A15 stiff wall tyres have certainly been 2553 (S) for at least the last 7 years, I do tend to rotate the tyres each event to try and distribute the wear as much as I can, but I do adhere to stamps outside on, L/F R/R . Assuming the car is Rear wheel drive of course.

redturner37
24-04-10, 11:54
One of the pleasures of this site is trying to sift opinion from fact.

My opinion is that BMTR and Radical are correct.

My observable fact is the absence of directional arrows on my Avon slicks. My previous set of ACB 10 had arrows on, my current set doesn't. My current set of Bridgstone slicks do have arrows. The instruction diagrams I saw on the Avon/BMTR site shows which way the tyres have to be mounted, subject to fwd or rwd. You pays your money and takes your chance, because if push came to shove and you had an incident because the tyres were mounted wrong, the suppliers would walk away from it, usual disclaimers. etc....

Craig Powers
24-04-10, 17:41
My observable fact is the absence of directional arrows on my Avon slicks.

BMTR usually chalk on an arrow. It best to label up the wheels in some permanent way.

Avon / BMTR provide a fitting guide.
http://www.bmtr.co.uk/avonrotation.htm

there is away of remembering

For REAR wheel drive....
to be RIGHT on the REAR put the WRITING on the RIGHT
by 'writing' I mean the batch/product codes.

The fronts on the real wheel drive are the opposite, ie Writing on left.

Front wheel drive is completely the reverse.

The rhyme courtesy of Tony Mekwinski @ South Shore Tyres , Blackpool

redturner37
24-04-10, 20:39
BMTR usually chalk on an arrow. It best to label up the wheels in some permanent way.

Avon / BMTR provide a fitting guide.
http://www.bmtr.co.uk/avonrotation.htm

there is away of remembering

For REAR wheel drive....
to be RIGHT on the REAR put the WRITING on the RIGHT
by 'writing' I mean the batch/product codes.

The fronts on the real wheel drive are the opposite, ie Writing on left.

Front wheel drive is completely the reverse.

The rhyme courtesy of Tony Mekwinski @ South Shore Tyres , Blackpool Of course, this always assumes that the purchaser understands what an arrow indicates.......

dennis.doyle
25-04-10, 17:18
A couple more common numbers you may come across are:
A89 (approx old A40) 12929
A15 6476
I don’t know how they rate in terms of sidewall stiffness, but they were as suggested by BMTR for a low powered ~500KG single seater for sprints.

gordmac
11-05-10, 14:50
The direction of rotation is to do with the direction of the loading on the tyre, on a rwd the drive is the load on the rear but the brakes are the load on the front and is in the opposite direction. Be careful with arrows, sometimes it is the rotation direction but sometimes the load direction, ie opposite to rotation on the front (rwd).

Ian Johnson
30-09-10, 12:43
sorry to resurrect an old thread but i'm new to the Slick Tyre seen, I understand the Rotation thing for the driven wheels but what about the undriven? as the load is purely for corner force (on a rear wheel drive) would it matter about swapping fronts from left to right and vice versa?

Forgive my niavety

Craig Powers
30-09-10, 12:50
sorry to resurrect an old thread but i'm new to the Slick Tyre seen, I understand the Rotation thing for the driven wheels but what about the undriven? as the load is purely for corner force (on a rear wheel drive) would it matter about swapping fronts from left to right and vice versa?

Forgive my niavety


I think that you treat the undriven wheels as having the opposite rotation because they incur braking forces as their major influence.

So with Avons for your single seater....

Rear (driven): Batch codes on Right on each rear wheel (right from drivers perspective)

Front (undriven): Batch codes on Left.

See the earlier rhyme.

See you at Anglesey

Regards.
Craig

Ian Johnson
30-09-10, 13:18
Cheers Craig, my dilema is the N/S front is about near the end of it's life but the O/S front has a fair bit of life left...........obviously the majority of Sprints that they have done have been right handed biased. Do i swap them....if i do what will the effect be? Anglesey is again R/H biased

sevaun
30-09-10, 13:31
Cheers Craig, my dilema is the N/S front is about near the end of it's life but the O/S front has a fair bit of life left...........obviously the majority of Sprints that they have done have been right handed biased. Do i swap them....if i do what will the effect be? Anglesey is again R/H biased
Ian,
Steve Owen gave me lot's of advice at an event a short while back. One thing in particluar he said was that that on un-driven wheels (fronts in the case of my OMS) it's a good idea to swap wheels side to side every few runs to encourage even tyre wear. As there is no excessive radial torque beeing put through the tyres he reckoned there should be no problem with delaminating of the tread when run against the direction of wrapping.
Hope this helps
Richard

Ian Johnson
30-09-10, 13:39
Ian,
Steve Owen gave me lot's of advice at an event a short while back. One thing in particluar he said was that that on un-driven wheels (fronts in the case of my OMS) it's a good idea to swap wheels side to side every few runs to encourage even tyre wear. As there is no excessive radial torque beeing put through the tyres he reckoned there should be no problem with delaminating of the tread when run against the direction of wrapping.
Hope this helps
Richard

Thanks Richard, this was my way of thinking.........guess i will find out at Anglesey in a couple of weeks time :D

Craig Powers
30-09-10, 14:10
Thanks Richard, this was my way of thinking.........guess i will find out at Anglesey in a couple of weeks time :D

Anglesey International, the faster of the 2 days, is probably about 2/3rd RH corners and 1/3rd LH (treating hairpins as 2 corners) so its a fair old mixture. I also would have no qualms about swapping the front tyres over.

btw I've stuck a video up on Youtube, link under the Anglesey thread, in case you are unfamiliar with the layout.

Send me a PM if you need any thoughts on gearing for your new car. I gear for 130mph @11k in 6th on the ZZR, and pull about 125mph @ about 10.5k rpm, which is the bike engine's correct red line. I reckon you will be 130+ mph.

Craig

Ian Johnson
30-09-10, 14:30
Anglesey International, the faster of the 2 days, is probably about 2/3rd RH corners and 1/3rd LH (treating hairpins as 2 corners) so its a fair old mixture. I also would have no qualms about swapping the front tyres over.

btw I've stuck a video up on Youtube, link under the Anglesey thread, in case you are unfamiliar with the layout.

Send me a PM if you need any thoughts on gearing for your new car. I gear for 130mph @11k in 6th on the ZZR, and pull about 125mph @ about 10.5k rpm, which is the bike engine's correct red line. I reckon you will be 130+ mph.

Craig

car max's out at 128mph so guess i will be flat out :D, done a few trackdays at Anglesey in Road cars so the circuit is familiar........and i did watch your vid, if i can break 90 seconds i will be happy ;)

Craig Powers
30-09-10, 15:44
car max's out at 128mph so guess i will be flat out :D, done a few trackdays at Anglesey in Road cars so the circuit is familiar........and i did watch your vid, if i can break 90 seconds i will be happy ;)

If you treat it as per Aintree you will be in the right ball park.
I use the same gearing for both Aintree & the Anglesey International layout.

Craig