What to do in 2020 - Fast Road Wheels & Tyres

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New Cat
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What to do in 2020 - Fast Road Wheels & Tyres

My crossflow seven is currently very nicely setup for fast road / B road use on 185/60/14 minilite replicas (Caterham supplied KN I believe) with Yokohama AO21 tyres. The gearing is spot on and the speedo very accurate. Having been flat floored it's also got a pretty optimal 80mm beneath the sump.

i can go longer buy AO21s and they will soon be illegal having swopped front to back to wear them all out. The cheapest most obvious option is to get a set of Toyo R888R in the same size as present but fear these will have to be medium compound because the softs simply seem unavailable.
 

If I move down to 13" then there don't seem to be any 70 profile options these days and anything less will certainly significantly shorten the gearing and result in speedo overread, never mind result in the need to mess with the ride height.

if I went up to 15" I'm guessing that there may be more tyre options but surely they will add weight and also may need new wing stays?

Any thoughts? Recommendations? Go Toyos? I'm loath to give up grip going to a regular road car tyre...

Toby S
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On my 1992 1400 Supersport I run 13x6 inch wheels with Toyo R88R's other than in winter -  185/60 on front but  205/60 on the rear - not only gives better overall balance but also gets the extra profile on the speedo wheels - 185/70 profile would be12.95cm, 205/60 is 12,3cm so still a bit of an over read but within reason (circa 5-7% against savnav speed - I know in winter when I'm running 185/60's all round, the over read is more significant when the profile drops to 11.1cm - serious over read of circa 15%+

Kind regards

Toby S

Toby S
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PS - the 205 width tyres on 60 profile also fill the rear wheel arches better from a pure asthetics point of view

 

Kind regards

Toby S

JonT
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You could also try Nankang NS2Rs which I think are available in 185/60/14 and somewhat track focussed. I'm considering those for my next set on 13s. Personally for road use I quite like road tyres, but I do drive in all weathers. I was disappointed Conti discontinued their Premium Contacts in that size, but I moved to Dunlop Sport Bluresponse which aren't quite as good, but have done ok with light track use as well as road. 

Having just had a quick search, I also see Vredstein have introduced a Sportrac in that size - I've been impressed with them in the past on other cars, so maybe that's worth a go too.

 

K7 VCT
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Ive ran nankang ns2r for 4 years nearly and happy, good value in 185,60,13. Having been monsoon weather last September in the Switzerland they can just cope with deep standing water. You learn to go easy if it's like that.....

Orange is my new black

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New Cat
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I'm now thinking to try the latest Yokohama AO52, albeit in 185/55/14 as they don't make a 60 profile. This will only result in a very small reduction in rolling circumference and ride height. Actually seems like the least compromise - never heard anyone using these on a seven but no harm in being the first. 
 

Ever since entering into a complete spin about 15 years ago (admittedly on an icy road) in my seven I've vowed never to fit hard road tyres ever again.

Tazio
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As someone who hung onto his A21s for a long time, I was torn on what to do, but my decision as to replacements would never never let the criteria be dictated by such matters as rolling resistance or speedo accuracy.  the cars are all about handling and grip, and for me that's what matters. And to select a tyre not normally associated with Caterhams, is to me very strange. Mines on R888R now.

Also why stick with 14s? , if you look at a tyre size comparison site for example, https://tiresize.com/comparison/  a 185/55/14, is lower geared than a 205/60/13, with the 13 inch wheel 22.7 inches tall against the 14s at 22 inches tall...food for thought, hopefully.

JonT
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Sticky tyres are more likely to be worse in cold conditions (<7C) than normal road tyres. I'd also expect road tyres to behave more softly at the limit, rather than letting go suddenly, albeit the limits will be lower in many conditions than sticky tyres. I think the A052s are now being fitted on some Elise models as standard so could well be a good option, but they're bloody expensive! They're also quite a new tyre, which might be why no-one has run them on 7s.

 

john g
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I'm in a similar situation, my 185/70x13 AO21's are pretty much 'gone' now and I'm looking to keep the same(ish) rolling circumference. 205/60x13 are available but would you fit these at the front? Over tyred? Heavy steering? Will they fit without touching the wing stays? Anyone tried them on the front?

An option is the Uniroyal Rainexperts in 185/70x13 which is probably the way I'll go.

New Cat
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My car was first fitted with Avon ZV1, an extraordinarily bad tyre for a seven! I also have a set of 13" wheels that I keep just for tracks/airfields with 175/55/13 CR500s that drop the ride height and the gearing substantially. Just have to be very careful in choosing my routes with only 50mm beneath the sump! Great acceleration but certainly stunts top speed too. With a 3.91 ZF LSD, I'm not keen on shortening the gearing significantly on the road. I've ordered the A052s now for just under £100 a tyre from Tyre leader (actually cheaper than R888R). The reduction in gearing is just 3%, so hopefully this will not be very noticeable. To be honest it's a much less expensive option than buying another set of wheels too. I've not heard a bad thing about these tyres but will let you know how I get on. Maybe it's an opportunity to put together my second YouTube video more then ten years since the last.
opplock
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"will let you know how I get on"

Please do. My car is on 14" wheels with rather old AO21s. I'd rather not have to shell out for a set of 13" wheels to get some decent tyres.