TomB Posted March 3, 2008 Share Posted March 3, 2008 Ive just bought a set of CR500 175/55/13. My previous tyres were 185/60/13. Will I have a problem fitting the CR500 to my 6x13 hubs? Ive got myself worried now that Im going to have too low ground clearance or they wont fit my hubs. The tyres have about 4.5 and 5.5mm tread left. Would it be best to put the more worn pair on the rear? My car is a 140bhp 1.8k, driven mostly on roads. I might do one track day per year - what sort of milage should I expect from them? Ive had Yoko A539s on for a long time now, so Im new to proper performance tyres on the 7!   Link to comment Share on other sites More sharing options...
mav Posted March 3, 2008 Share Posted March 3, 2008 They'll fit your wheels, and the wheels, assuming no change fitted your hubs ok previously??? you will have a difference in ride height and you can detmine that form any of the online wheel size calulators - you'll find plenty of links in the archive... Link to comment Share on other sites More sharing options...
TomB Posted March 3, 2008 Author Share Posted March 3, 2008 So, by my calculations on an online wheel calcualtor, the car will sit 15mm lower. Thats a bit worrying for road use! Might have to think a bit deeper about this. Might end us selling them again & getting tyres that fit!! Link to comment Share on other sites More sharing options...
tricky dicky Posted March 3, 2008 Share Posted March 3, 2008 Tom, Have you adjustable spring platforms? If so these can raise the car, from memory you are dry sumped and as long as shockers and springs are in good order I'd say you'd be ok. You know my history with bashed sumped and K series. That was as a result of worn shockers. I think you will find the CR500's a marked improvement over A539's in terms of grip and feel. My experience was of steering that felt more responsive and a car which tramlined less. Good in wet too. Go for it! Rich Link to comment Share on other sites More sharing options...
TomB Posted March 3, 2008 Author Share Posted March 3, 2008 Yes, Ive got adj platforms, just not sure I can be bothered with having to adjust them! Im going to put new tyre next to old which are still on the car to compare them. I also need to measure under the sump to see what Ive got to play with. Link to comment Share on other sites More sharing options...
rgrigsby Posted March 3, 2008 Share Posted March 3, 2008 You really need to have the CR500 on a rim to compare it properly, the size when not a rim isn't truely representative. Rob G www.SpeedySeven.com Link to comment Share on other sites More sharing options...
TomB Posted March 3, 2008 Author Share Posted March 3, 2008 Why, does the size of the tyre change much?  Ive checked tonight and they do indeed appear to be 15-20mm lower than the existing tyre/ wheel comb. There would be about 5cm under the sump which is getting a bit on the low side. Given the cost of the CR500 tyre, I dont think it will be a long term tyre choice, so rather than fit them, adjust suspension, then fit 185/60/13 AO21R for example, when they wear out, and have to lower the suspension, Im wondering if its better to change my mind & try and sell them on. I should have thought about this before I bought them!!!  Edited by - TomB on 3 Mar 2008 22:59:08 Link to comment Share on other sites More sharing options...
Area Representative Paul Richards Posted March 3, 2008 Area Representative Share Posted March 3, 2008 Tom It's not a big job to raise the car using the adjustable platforms, but if you do decide on AO21Rs, go for the 70 profile if you are worried about ground clearance. Some don't like the look of the bigger profile, but they are quite a bit cheaper and a good all round road tyre in my opinion - See you Wednesday.  Paul Richards Area Representative - L.A.D.S. (Lancashire and District Sevens) LADS Website Growing old is compulsory - Growing up is optional Link to comment Share on other sites More sharing options...
TomB Posted March 4, 2008 Author Share Posted March 4, 2008 Im happy with the ground clearance on the current 185-60-13. With every thing else left to do to finish the winter project, Im not sure I want to add ride height adjustment to the list as well. So far Ive still got scuttle, windscreen, seats & runners, brake master cylinder & bleed system, electrical checks, interior carpets, tyres and alternator repair and service before its back on the road, and spring is rapidly approaching!! Link to comment Share on other sites More sharing options...
Area Representative Paul Richards Posted March 4, 2008 Area Representative Share Posted March 4, 2008 Tom "Quite a bit cheaper" 😬 😬 😬 😬 😬 Paul Richards Area Representative - L.A.D.S. (Lancashire and District Sevens) LADS Website Growing old is compulsory - Growing up is optional Link to comment Share on other sites More sharing options...
Jaseb Posted March 4, 2008 Share Posted March 4, 2008 I found that with the CR500's fitted acceleration is noticeably improved... Just a thought 😬 Link to comment Share on other sites More sharing options...
TomB Posted March 4, 2008 Author Share Posted March 4, 2008 Sod it, dont want the hassle of ride height adjustment - back for sale! Should have thought about it before I said yes!! Link to comment Share on other sites More sharing options...
naddy Posted March 5, 2008 Share Posted March 5, 2008 Tom, I went through pretty much the same process, with the exception that I had a set of rims with 539s and a set with AO21R at the same time & could directly compare. The 539s were unlikely to ever wear out!! and thats all you can say really lol (i still have 'em and they've loads of tread left!). The AO21s gripped fairly well most of the time, overheated and went blue on a trackday once and were as durable as a soft cheese. I went through a few of these (AO21s) and hesitated about CR500s because of A) cost and B) ride height faffing. Now then, having taken the plunge, there's no way I would go back. Ever. They are very very durable (which offsets the cost) IMO in comparison with AO21s and grip very well on wet or dry roads and on track. Compared to the other tyres I have used they have no vices whatsoever (I have only used 539s and AO21s though so others may feel differently, I realise). Stuarts post on your locked 'for sale' thread is spot on . Keep 'em and sort the ride height. As a spin off from this, I discovered that my car was pretty poorly set up anyhow and as a result of the flat flooring exercise and sorting some of the geometry the car was transformed, for the better, and had a sensible ride height. 😬 If however you do wish to part with them, I might be interested  Nick Link to comment Share on other sites More sharing options...
TomB Posted March 5, 2008 Author Share Posted March 5, 2008 Thanks for you advice Nick. The tyres Im replacing are A539. As youve probably guessed from the for sale post, Ive decided not to do anything too hasty. Oner minor concern is with even smaller wheels, my rear arches will look even emptier than now! Just a cosmetic issue I guess. Did you have 13 inch rims too? Incase I do get rid, where abouts are you? Â Â Â Edited by - TomB on 5 Mar 2008 12:05:21 Link to comment Share on other sites More sharing options...
Area Representative Paul Richards Posted March 5, 2008 Area Representative Share Posted March 5, 2008 Tom I suspect you'll bump into each other tonight 😬 Paul Richards Area Representative - L.A.D.S. (Lancashire and District Sevens) LADS Website Growing old is compulsory - Growing up is optional Link to comment Share on other sites More sharing options...
TomB Posted March 5, 2008 Author Share Posted March 5, 2008 Oh - that Nick! Link to comment Share on other sites More sharing options...
naddy Posted March 5, 2008 Share Posted March 5, 2008 Yep, will be at LADS tonight 😬 Yep, have 13 inch rims I had the concern about rear arches too, but as you say, they look a bit lost now with a 6 inch wheel so I wouldnt worry about it too much. The main issue is quite rightly ride height - and it's fixable if you have the adjustable platforms. If, and i stress IF, you want to start worrying about the cosmetics - then it goes on and on I got around it by going for 8 inch rears (so actually your tyres wouldnt fit mine, doh!), and at the front having the wingstays cut'n'shut to shorten them. Then the wingstay cracked where it had been welded, which cracked the CF wing, which I managed to repair with a bit of advice and encouragement from somebody I think you know, who seems to love renovating CF himself . That same person also very very kindly welded my wingstay back together (he hadnt done in the first place, I should add) and since then all has been well.  but doing all that for cosmetic reasons is a shallow and worthless persuit 😬. dont do it!! get the cr500s on and sort the ride height!   Edited by - naddy on 5 Mar 2008 12:33:32 my spelling  Edited by - naddy on 5 Mar 2008 12:34:47 Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted March 5, 2008 Leadership Team Share Posted March 5, 2008 Was that the door bell I heard 😬 Joint Area Representative MAD Sevens (Merseyside And District) www.superse7ens.co.uk..........the rebuild 😬  Link to comment Share on other sites More sharing options...
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