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MG Midget and Sprite Technical - Tyre size comparison.
|Is there a definitive accurate website to compare sizes?|
What is the nearest radial?
Is it 175/70/13 or 165/80/13?
|The best and most comprehensive website no longer operates, so I offer this. -|
560-13 - 175/70R13 (Radial 70% ratio) - 155R13 (Radial 80% ratio)
Towards bottom of page - https://www.vintagetyres.com/tools/
|Thanks Nigel. That's a useful table.|
|Probably not definitive, no.
Crossplies started off more or less tubular so close to 100% aspect ratio and gradually shrank down towards 80-something%, which is where radials came in (which were 80% unless marked otherwise, as all lower profile ones now are). Calculators for early tyres will therefore be making some assumption about how big they might have been.
Nearest radial will likely be the 80% one. My car used to have 145R13 (80% by default) before I swapped to wider/lower profile.
Longstone have some advice, and can still do crossplies if you wish!
|I believe the non specified ratio for radials was 82% though I have no idea why.|
|Thanks for that explanation Adrian.|
|Figures with tyres (such as width) even now can be nominal and could vary with manufacturer and even model or size range.
In the past I've read of the old tyres being 81% or 82% but taken as a nominal 80%, again that might have varied with manufacturer or for other reasons. Or it might not have been so at all. I've not seen anything definitive or conclusive but I've not done that much research and things like this tend to get lost in the mist of time. I could start spreading the figure 79% on social media and perhaps in the future Google would throw this up as a known fact.
|Nigel, I said I didn't know why. I wasn't meaning I didn't know why it was 82%, but meant that I didn't know why I thought that!|
Why, when they are quoting aspect ratios, is it not at a quoted tyre pressure and temperature. It must vary a lot in practice. And with some tread patterns with very rounded shoulders, you wonder where they measure the limits of the tread width.
|Good point. There are two circumfrences. Static, and rolling, which Continental for one, quote at about 40mph from memory.|
|37mph to be accurate. I've just looked in the archives. It's a rabbit hole we've been down before. |
But anyway, I have what I need. I'm contemplating 175/70's on my Capri, as they will come with a set of cobra slots-- if the price is right, and they are the closest to the original 5.60 crossply in 1963.
I wasn't questioning your thinking and I think I read it as you meant, or I might have misread it to what I thought I read or meant.
I was just throwing in the 81%, and 82%, from my memory of the subject, which might or might not be correct, my memory or the figures.
I hope that has cleared things up.
Google informs me that 37mph is 59.5457 kph, perhaps we could say this is 60 kph, as Continental are a Germany company so don't use the Imperialist measurements of the St George's Cross.
|I bet driving a Capri on crossplies was fun. |
And yes, if you watch videos of old racing cars you can see the tyres grow as they accelerate. [Failed to find an example, sigh] Nowadays I think only obvious on dragsters.
Anyone tried Blockley tyres in 145 SR13 on a Spridget: https://www.blockleytyre.com/product/145r13
|Not on a Spridget but I know of a couple of people who use them on other cars and a different size but they think they are good.|
I'd try them in an instant with the 1,000-mile guarantee but note the maximum wheel rim width is 4.5", unfortunately my rims are 5".
|1000 mile guarantee huh? Such much.😅, for 74 quid a pop. Hoping of course, that they don't pop.🤣|
|An update on the pair of new uni rain expert 3s I put on my Sprite. Still on the fronts, I may try them on the back again at some point, but very happy on the fronts. Good grip, and might be in my mind, but the steering feels lighter.|
Edit. Didn't get the slots for the Capri. Turned out to be a pair of 5.5's, and a pair of deeper dish/offset. I want 4 the same if anything.
|Guarantee wasn't the best word to use, I was replying to Mike who's actually been to the Blockley site.
For those that haven't been to the Blockley site or can't be ar*ed to click the link and read, here's what I meant. -
"As with all Blockley radials, drive normally for 30 miles or so, then use them as hard as you want for 1,000 or so miles, and if you are not convinced these Blockleys are the best tyres you've driven on, we'll have them back for a refund!"
If you saw the 1959 Mini video where Ivan was driving like "nutters" down the farm track "thro' the gate doing 98" and knocking it out of gear, that was on Blockleys tyres made for that model.
Link to that video for the fun of it! - https://www.youtube.com/watch?v=xjnV1gDudko
|Right fair enough. A chance to hammer the tyres for free is quite a good deal.|
Just watching the vid' until he opened the bonnet, and I could see the dynamo was stationary, I was thinking, 'kin 'ell, never mind how original it is, that engine is f*cked. 🤣
Btw, who's Ivan when he's at home? 😁
|I don't usually bother watching these kinds of videos. But that one is pure joy. Who hasn't had a mini? I was in the driver's seat hacking it down those lanes and passing the slow stuff in the way. |
Brilliant, cheers Nigel.
Makes me want another bog standard mini. Fun cars. Simple easy fun.
Through the gate at 98.🤣. Game old bastard still.
Any idea where that is?
|Whatda mean the dynamo is still, the engine was off then, you'd better get down to Specsavers and ask for a free old fella's hearing test.
I've no idea who he is when he's at home but from the little I know he's Ivan Dutton, does stuff with old Bugattis in a shed out near Ickford near Thame.
You must have forgot or not seen (you've forgot, you're old) a previous thread(s) where his mechanic was getting a two-cylinder A-series engine going on a stand, that was what you could hear (well you might not have) at the start of the 1959 Mini video.
Usually driving videos bore me but Ivan's got a great and amusing way about him and the Lotus 7 video I thought was great.
In case you missed them -
The test drive section on this vid is fabulous, Lotus 7 racing car SOUND 1957 - Ivan's Shed - https://www.youtube.com/watch?v=kat79zrVDQg
Finalisation - Mini 2 cylinder prototype Part 6 - Ivan's Shed - https://www.youtube.com/watch?v=qs0XL_8vB1o
|Yep, exactly the engine was off. But every time the camera got closer to the car, it sounded like that engine racket was coming from the mini.
I didn't follow the 2 cylinder a series thread. But I did have a mate with a mini with a fooked engine, in which one piston fell off it's rod, and it made it from welling garden city to streatham, sounding just like that video. So I naturally thought, ---- 😁.
I agree, he's an entertaining bloke to watch. But it was having a mini myself, and driving it pretty much like that, made me feel like I was in it, that gave me most enjoyment. Not sure I'd have been his cameraman though. Lol
|I think the camera angles made it look faster than it was, look at the speedo, even if it is actually accurate rather than over reading. Remember this is an original 850, even the later 1000 struggled up hills.|
For some months I had a 6-month old 1996 Rover Cooper 1.3i, as I couldn't afford a 60s Cooper, not fast but fun on quick manoeuvres.
|Couldn't afford one now. You seen the bloody prices of 60's coopers?|
The standard Mini 1000 I borrowed for a month or so had no problems on hills and a girl I knew had an 850 Mini auto which again handled hilly Bath easily. Used to go up a local hill in my Austin A40 Farina at 60mph, not legal now as they've dropped the speed to 40mph.
|Back then the Rover cost me IIRC £6k and a half decent 60s 1275 Copper was £8k. Fun cars but neither worth that money even back then. I'm sure there are more "genuine" 60s Mini Coopers around the world than were ever built at the factory. Unless bought by a sherd investor they're only worth what some idiot is prepared to pay, same as all "classic" cars.|
those Minis must have been in better state of servicing and tune than average then or they had a run up or not comparing with other cars.
A mate had a 1000 back in the day but he was a slow driver anyway, when he got a s/h Mk1 1600 Cavalier next he thought it was a luxury car, despite the heavy motorway steering.
The only time I was out Bristolish/Bath sort of way was when I drove my elderly neighbour's Mini Metro 1000 and he said he didn't realise it went that fast as I tried to gain momentum for a long hill I could see coming up, we made it easily but lost speed going up.
A mate's Mini was like Ivan said in the video, the speedo needle went into the gauge at the bottom and he told me it would go to the stop, no doubt well over-reading, Perspex windows, stripped out interior with roll cage, straight cut box, high cam engine - and all I could hear was the bloody noisy dual fuel pump, probably one of those nasty SU things. I'm glad I wasn't driving it on the road, it hopped about at low revs and speed.
|I rallied a cooper S for a while. Good old night time plot & bash 120 car entries around the back lanes of Wales. I and a mate (you entered as a team and we took turns at driving & navigating) won the Welsh National championship for our class (novice) in 1972. That was in a different mini,not a cooper. The handling was completely different, not just the increased power of the S, but the balance and change in traction between front and back made it a totally different car to handle, especially on the forest stages.|
|You're a dark horse Guy. I don't recall you mentioning being a racer or winning prizes. Tell us more. Sounds interesting.|
|I confess having to look up the meaning of "plot and bash". I keep learning from the bbs! Although, I once did a coĺlege motor club rally in my first car, a Ford Anglia (bog standard). I think we got lost......|
|Its all a very long time ago now Anemn! We gave up when it began getting too expensive and I realised that to progress you needed to be much better than I was and have some sort of backing. But it was fun doing stage events and then comparing times with some of the top international drivers who had travelled the same route in the same event perhaps half an hour earlier. Certainly took one down a peg or two! But did get a mention in one issue of Motor Sport as far as I recall. ;-)|
|They later stopped doing them, largely on safety grounds. The road sections were on public roads. I am not sure now if they were even closed, though they were heavily marshalled. But they relied on accurate navigation off OS maps and it was possible to go astray and end up on the wrong roads. Plus as there were 120 cars, setting off at 1 minute intervals, by the end of the night tail enders 2 hours plus behind could be mixing it with tractors and milk tankers.|
|Well it certainly sounds like you had a good time doing it, and got recognition to boot. That'll do. 🙂|
|Do you have the copy of that issue Guy?
Anyone else appeared in national print?
Back in the day I had a Morris Mini Cooper, snowberry white over island blue IIRC. Loved it. The PO had fitted a 10" steering wheel so you changed direction more by thought than action. He'd also fitted a piece of gold painted fibreglass under the front bumper which I was told was a 'spoiler' designed to make the car faster. It probably knocked a couple of mph off the top speed in reality.
I remember needing a fan belt and pulling into an Austin garage where the truculent mechanic told me he only sold spares for Austins, I said I'll take a chance that a fan belt for an Austin Mini Cooper might fit. Unsurprisingly it did.
Fond memories of that car. It is still on DVLA's (JWM674F) website but untaxed since 1979 and either in a barn somewhere or long since crushed.
you'll probably find it's a few cars in Japan and other places, perhaps not the same colour or even model but definitely a Mini Cooper(s). 😁
|One time when we stopped at the Y Llew Coch (Red Lion) Dinas Mawddwy they had a night rally of classics stop there at the end for breakfast from 3am, about 100 people. We though we'd get up and look at the cars as they parked up but we just looked at a few through the room window, mainly 80s cars, and then went back to sleep, so tired from driving the fabulous roads ourselves.
Including Bwlch y Groes (pass of the cross) the old Austin test road and climb on the second highest public road mountain pass in Wales.
In the public bar earlier in the night we heard tales of previous years' rallies with farmers repairing stone walls when some local participants had gone wrong.
Gosh your recollections brought back memories of similar exploits in a Lotus Cortina (I was the navigator as it was not my car!) All over and around Salisbury plain and the surrey hills. Never won anything though.It was blooming exhausting being awake all night but in your early 20's anything is possible. Sadly I recall the Cortina ended up in a ditch and was written off
This thread was discussed between 30/09/2021 and 31/10/2021
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