mk1-forum.net

Thanks Turbocox,
We found, back in the 80's, that suspension and steering geometry changes help take advantage of whatever tyre we ran (yoko A001's were prefered) and we could dial in a wide range of handling traits. Our mid-engined cars were much better with quite a lot of castor as a starting point then fine tuning with tyre pressures, roll bar stiffness etc. Using standard mini subframe pickup points front and rear does pose a few problems with the car carrying the same roll centre height at both ends, not an ideal starting point.
If you can, try getting to a 750 Motor Club meeting and have a look at the "sports special class" quite a few mid-engined and running yoko's O32/O48 etc and they work very well. Give the O32's you have, another go and fiddle about with your suspension, the rewards are there.

Good luck Ian.

I had A008s on my Force 6.5" wide rims and TBH they wernt all that stretched (i HATE this modern stupid idiotic stretched stance look) .

Used them for years, tyres lasted very well, and i only sold them as no-one in SA could balance the 10" Force rims as they couldnt fit on the new machines, and as i used my Mini daily, the steering wheel shudder at 120kph was horrid.

I put 032s on my force rims before stretching was fashionable. I did this because I wanted the sidewall flex to be negligable. You get a nice break away, rather than a "losing it". I found that a rear ARB did the same thing. You either corner flat at high speed, or chuck it to get the back sliding. I ran -1 deg on the back and 0 deg tow. It worked fine.

The best tyre/wheel setup I every had for very fast road seemed to be a set of Kelly Springfield KR-5 tyres (very stiff sidewalls) on Dunlop D1s.

Had ASBO gone back on the road, it would have had Avon's on 4.5 minilites. Again, due to the stiff sidewalls. The 4.5 minilites were a style choice, rather than what is best. (5" IMO)

I sometimes wonder if minis have got too valuable and I've got too sensible for hooning down country lanes.

The most enjoyable setup I had was running a set of 3.5 steels with 5.20 crossplies with my 1380/286 engine. They didn't last very long, but you could do the most ridiculous 4 wheel drifts in it (on a test track of course)

All interesting stuff.

Is there anywhere a history of racing/ road tyres particularly in 10" ? I am never too sure as to what tyres were available in the sixties . 12" racing tyres seemed to make an appearance in 1968 or so but it looks like they were fairly tall profile or was it that they had to run a fair ground clearance in group 2 (Britax , Vita)

Anyone have any experience of A032's vs Avons?

Tim Harber wrote:
Anyone have any experience of A032's vs Avons?

avons are a thousand times better

when I tried a032's I could destroy a front pair in 30 min

a pair of avons would last all season

Well, I've had a008s on 4.5 rims and had a horrendous weave over 80 mph, no matter what I did with tracking, camber, corner weights etc. There was always a feeling that the car bounced on the tyres rather than the suspension working too. Plus, the tyres rubbed on the inner rear arch when pressing on.

Fitted 4.5 minilites and Avon tyres, all problems disappeared.

Tim Harber wrote:All interesting stuff.

Is there anywhere a history of racing/ road tyres particularly in 10" ? I am never too sure as to what tyres were available in the sixties . 12" racing tyres seemed to make an appearance in 1968 or so but it looks like they were fairly tall profile or was it that they had to run a fair ground clearance in group 2 (Britax , Vita)

If its any help in the early 1970's my brothers 'Free Formula' 850 Special Saloon Mini racer was running on Firestone 1B19 6.0x19.3x10 dry tyres on 6x10 Mamba alloys with Dunlop CR65 Mk11 (320) 5.00L-10 used on S reverse rims for the wet. As I remember most of the front runners switched from Dunlop dry tyres to the Firestone 1B19 when they first appeared on the market and achieved quicker lap times.
viewtopic.php?f=4&t=12093&start=90#p141890

Anyone have any experience of A032's vs Avons?

Avons are the best tyres i've had ( A008, A032, camacs ) ... and that was a 12 years old used set.
On 5" rims they gave much better control and less understeer then others on 6" rims.
28Psi all round upon's Rich advice


Avon's cost is THE problem .

Cheers
Luis

mab01uk wrote:

Tim Harber wrote:All interesting stuff.

Is there anywhere a history of racing/ road tyres particularly in 10" ? I am never too sure as to what tyres were available in the sixties . 12" racing tyres seemed to make an appearance in 1968 or so but it looks like they were fairly tall profile or was it that they had to run a fair ground clearance in group 2 (Britax , Vita)

If its any help in the early 1970's my brothers 'Free Formula' 850 Special Saloon Mini racer was running on Firestone 1B19 6.0x19.3x10 dry tyres on 6x10 Mamba alloys with Dunlop CR65 Mk11 (320) 5.00L-10 used on S reverse rims for the wet. As I remember most of the front runners switched from Dunlop dry tyres to the Firestone 1B19 when they first appeared on the market and achieved quicker lap times.
viewtopic.php?f=4&t=12093&start=90#p141890

A bit depends on which Dunlop dry you used. IB !9s were probably better than 700 CR81s, but against 900 it was probably personal preference. 900s were probably too wide for an 850. Possibly anything was better than a CR70. Again it ended up personal preference between IB19 and Dunlop slicks or car setup.

So will we start a new thread on 60s/70s Mini tyres?

[quote="ivor badger 2"
So will we start a new thread on 60s/70s Mini tyres?[/quote]

I started to think about tyres when I did a hillclimb in a friends car on aged Avons and was impressed then I did another on CR65's and was suitably embarrassing with my efforts on a tight twisty track.

Later I did idly ask whether I could run a car in the A series challenge on 12" CR65's (my 7 port thing) and got a tentative affirmative but the 12's only come in a tall section and a bit expensive anyway. I guess that Swifty used 13's at Goodwood as the tyre choice allows for more modern stuff as 13" CR65's are even taller(hacking front wheel arches out to clear tyres a la Sportspack.

I was wondering what section the 12/13" tyres were on the late sixties circuit racers.

As the old stuff is a bit water under the bridge I can't see it being of much interest to most folk

Idle thoughts......

Not that I can contribute to a 60s 70s tyres thread.

But I think it would be very interesting. Reading about the works cars when they raced, there is often an interesting tyre story present.

A few people have suggested it. Why not see what the interest is?

Tim Harber wrote:[quote="ivor badger 2"
So will we start a new thread on 60s/70s Mini tyres?

I started to think about tyres when I did a hillclimb in a friends car on aged Avons and was impressed then I did another on CR65's and was suitably embarrassing with my efforts on a tight twisty track.

Later I did idly ask whether I could run a car in the A series challenge on 12" CR65's (my 7 port thing) and got a tentative affirmative but the 12's only come in a tall section and a bit expensive anyway. I guess that Swifty used 13's at Goodwood as the tyre choice allows for more modern stuff as 13" CR65's are even taller(hacking front wheel arches out to clear tyres a la Sportspack.

I was wondering what section the 12/13" tyres were on the late sixties circuit racers.

As the old stuff is a bit water under the bridge I can't see it being of much interest to most folk

Idle thoughts......[/quote]

Just to make a point. Tim, you race on the same tyre casing as supplied for minis in the mid 60s.