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MG Midget and Sprite Technical - '77 1500 tyres

Need new rubber. . . 145-80-r13 are the ones on it. i take it this is correct.

Where do people source their tyres?
d j kirk

Fishers in London would be able to help. MGOC recommended and they have done a lot of work on MASC Kent members cars
R Williams

as per Driver's Handbook

it depends what year your car is and wire wheels, steels or pressed steels

if you have Rostyles then yes 145/80/13

you could add your car details and make your vehicle profile for view to save guessing which model and year you have

Nigel Atkins

or you could read the title of the thread Nigel ;) :p

145 80 13 are the original size for the steel wheels. I've not personally ordered from but have heard good things about camskill, and tyrewizard (google job) and I have used blackcircles with included local fitting, which was great :)
Rob Armstrong

I have used Camskill. You buy online and get to read up on all the tyre qualities from a wide selection so can make a proper choice. Unlike KwickScam and others when you get no information and little choice.
Much cheaper, free delivery and l then used a local mobile fitting service who were excellent.
Guy Weller

D J,
sorry I forgot the thread title, can't help with where to source them other than to say there can be big differences in price from one place to another and then quality of installation even thought there's not much to that - wheel balancing can sometimes be interesting on those wheels

Rob,
thanks, I must admit I forgot the thread title, doh, rushing too much

I was trying to get a bit more info from posters (admittedly it was in the thread title this time) in case of follow on questions that often happen
Nigel Atkins

Hi D.J.

Your car would have originally been fitted with 145SR13 sized tyres. These had an aspect ratio of 82, and so a sidewall height of (145*0.82=) 118.9mm.

Tyres are no longer sized in this way, you could either go with a 145-80r13 (as you currently have), 155-70r13 155-80r13. These would give sidewall heights of 116mm, 108.5mm and 124mm respectively.

The 145-80r13 is quite a close match to your tyre, the same width and only slightly smaller in diameter, however if you wanted to up the grip and diameter a tiny bit, the 155-80r13 is a good choice.

Myself and C.L. Carter went with Uniroyal Rainexperts in 155-80r13 (from Camrider) and have been delighted with them. They are a bit softer than your average tyre, and grip tenaciously.

-- Josh

P.S. It might be worth checking with your insurer if minor changes to the tyre size matter, mine have never cared.
Josh L

Another vote for Uniroyal Rainexperts - I use a different size for my K-midget but they grip well in wet and dry. I used tyre wizard and had them fitted via JLH Minors.
Johnathan

And by Camrider I mean Camskill!

-- Josh
Josh L

note tyres sizes are nominal so figures are not millimeter perfect, not that it matters to be that accurate - you can have the same stated size tyres that vary slightly and variances in the same model of tyre over the size range

just so you know that the same size tyres can vary slightly in size and fit as well as performance
Nigel Atkins

yes the uniroyal rainexpert are great... good tyres... at decent prices... buy them online and have them sent to your fitters...

the ones josh mentioned are that little bit wider but not silly wide - so you get a smidge more grip that the 145s
C L Carter

you don't get grip from the tyre size as such, it's from the compound make up and when the tread design

allowing for the variances mentioned earlier in tyre size across different ranges and models of tyres, 155/80/13 will lift the car very slightly compared to 145/80/13 and 155/70/13 will very slightly lower the car, plus other differences of course see - http://www.carbibles.com/tyre_bible_pg4.html

there are many threads about tyre selection in the Archives but all that used the Yoko A.drives gave them very good reports, I wish I still had them on now
Nigel Atkins

Not only will they lift the car, they will also affect the gearing (by a small amount).

The most important recommendation I can give is DON'T get 145-70r13 or 155-70r13 tyres!
These are too small, reduce the gearing, and look pretty silly.

-- Josh
Josh L

Josh,
sit down, hold on to your socks - I agree with you (don't tell C L or he'll be jealous)

I added the link for differences in gearing plus that page and the other three pages and the whole site give loads of useful info

I also agree that 145/70/13 will look too small, they were fitted to Tim Lyman's car when he got it so there are photos in the Archives

I'm not so sure that this is so much so with 155/70/13 but perhaps it is more pronounced on a factory standard ride height 1500 than the earlier chrome bumper models at factory standard ride height

I run 155/80/13 (on my 5" minilite copies) but my car sits at factory standard ride height so has plenty of wheel arch clearance above them and they don't 'fill' the wheel arch as is the modern fashion, in fact the oversize makes them look more like classic size than the correct size
Nigel Atkins

175/70x13 Rain experts on 5.1/2"wires on my '65 Sprite look great and grip fantastically. They don't look at all too small.

Bernie.
b higginson

Picking up on what Nigel said, wider tyres don't automatically give you more grip, or even more rubber on the road. Consider two tyres, one narrow and one wide. The weight of the car is constant, so if both tyres are made of exactly the same compound, the patch that is actually touching the ground is identical with both the wide and the narrow tyre. For the narrow tyre the patch is long and thin, and for the wide tyre it is short and fat.

In reality, wider tyres are often of a more modern design than narrow tyres, so may be made of a softer compound which will give more grip, but will wear quicker.

Low profile tyres upset the way a tyre behaves by making the wall stiffer, so the tyre deforms less when cornering. The downside is that it has less resilience to bump absorption, and so gives a harsher ride.

On a car that was designed for a certain type of tyre, the fitment of much wider, stickier tyres can upset the handling, rather than improve it. My Elan Sprint was deisgned for 155 x 13 radials and these contribute to its beautifully balanced handling. Putting big rubber on it spoils the delicate feel of the car.

On my Midget, I had 5" Revolution alloys and I fitted 165/70 x 13 Barum Brilliantis tyres, as recommended in Which magazine. They are excellent, wet and dry, and seem to suit the car. Barum are the economy arm of Continental tyres, so are of good design and quality.
Mike Howlett

to add to what Mike has put - sidewall stiffness can vary even with the same stated size tyres, from one make and model to another

the link to to the Tyre Bible will take you to information that confirms what Mike has put plus loads more useful info

since last November tyres have been labelled for (fuel) economy, braking on wet roads and noise but take the labeling with a pinch of salt, a good tyre that has mediocre labeling results is still a good tyre

http://www.michelin.co.uk/tyres/learn-share/buying-guide/future-tyre-labelling
Nigel Atkins

Nigel you get more grip from tyres which are wider because you have more road contact area. Yes there are other factors - but it is stupid to suggest that larger tyres don't give more grip.

C L Carter

I think the use of the word stupid should be banned from bulletin boards. I certainly don't appreciate being called stupid, and I don't suppose Nigel does either. I am not always right, but I am not stupid.

However, as I clearly said before, if you have a narrow tyre and a wide tyre, both made of the same compound, and both fitted to the same car, the amount (or area) of rubber in contact with the road will be identical for both, and therefore the grip available will also be identical. What muddies the water is that wide tyres are often made of softer compounds, so they squidge out more and THAT may put a little more contact on the ground, and will certainly give more grip, at the expense of wear.

More grip isn't always a good thing. 60s and 70s sports cars are so easy to handle because the grip levels are fairly low. The driver can feel (through the seat of his/her pants) when the grip is being lost and can correct it successfully, because the speeds are relatively low. A good modern car grips and grips until suddenly it breaks away, by which time you are going too fast for Mr or Ms Average to do anything about it. If you aren't an enthusiastic driver, that isn't going to be a problem because you are unlikely to reach the limit of grip. But if you like pushing on and exploring the limits of what the car can do, I would rather be in an older car. I reckon I can cope with that.
Mike Howlett

Mike,
for a youngster calling someone stupid is very mild, remember that lad that put I should go back to having tea with my husband :)

C L and I have a bit of banter, so he'd have been only referring to my post and possibly not seen yours (I hope) first thing I was going to do was reference your post and the tyre bible, again

tyres and their construction does seem to be as much an art as a science

I do many stupid things but generally I'm not stupid, probably average intelligence but that's only because the average is low

I've swapped tyres before to get less dry weather grip and in fact have recently done it on my Midget, the difference was greater than I wanted but I'm just now getting used to it

but you can't expect youngsters to pick up on things like this without persuasion (I use repetition) because it's against the current fashion and what they're told by others of their age - weren't we the same, except we wouldn't call someone stupid or worse, well not to their face (or write it)
Nigel Atkins

I was indeed referring to Nigels post - I certainly wasn't referring to a person be it nigel or you mike. I stand by what I said, it is stupid to suggest wider tyres don't provide more grip. Science. Fact. End.
C L Carter

oh to be so young and so certain about life

and to be fair when any fact is followed by End then that is conformation of that fact :D

perhaps if Lawrence was here, and if he agreed with us, a possibility might be entertained

and Lawrence would email a tyre manufacturer to confirm, I can't be bothered, I am happy to be proved wrong as the older you get the more you learn if only because you keep forgetting what you learnt other than how little you know
Nigel Atkins

There are too many other factors and variables involved to be able to be quite so emphatic that wider tyres give more grip. Try driving a car with very wide tyres on snow, when compared with a narrower tyre - the latter grip far better!

I think this is one reason why so many drivers struggle nowadays with modern cars on snow. The width of tyres has generally been increased largely for aesthetic reasons, but also giving better grip in normal road conditions and requiring less driver skill. But then get onto the slippery stuff and the wide tyre has less contact pressure, less grip and is harder to control.
Guy Weller

Guy, thats why its so much fun to drive with wider tyres, and it makes your car look more manly insted of a shoppingtrolly. :)

I run 175-65-14 and only because of the restriction the square arches give otherwise I would go even wider (185/195?)


See the difference between the standard frontwheel and the rear?
Could give a bit of a handicap in the snow but your the absolute king on the dry!! :)


Arie de Best

Hi Arie,
I wasn't necessarily arguing in favour of narrow section tyres - excepting for snow driving. But you can also go too wide. Wider tyres absorb more power. And anyway one wants to have a tyre that lets go a bit to make roundabouts more interesting! I use 165/70R13 and they don't seem to slow me down too much on my favourite roads! ;-)
Guy Weller

wider rubber is also heavier. Even more so when relative to a light car like a spridget.

The grip thing (after a short and brain melting google session) is massively complicated, in fact far too complicated to summarise with an X is better than Y statement.

And that's before getting into the madness that surrounds slip angles and breakaway characteristics...

Modern wide tyres are hopeless on snow. A combination of large circumferential grooves (great for water, rubbish for snow) and very poor driver feedback (drive by wire anyone?) makes the midget an attractive proposition when it gets slippy. Unless there's a hill, which it won't go up. It's still better than the P6 though, with fatty tyres and rubbish throttle control through the autobox.

As an interesting addition, I've driven a standard midget on 175 tyres and it feels quite odd compared to the K with sorted suspension on 175s. In fact I drove a standard 145 equipped car and was reminded how light and nimble the original setup was, something which I think is lost slightly with the wider tyres. Even though steering was an issue with the standard wheel and seats and my long legs and larger beer induced circumference I'd say that the standard on 145s was a nicer steer than the standard on 175s. Not for the K though, I can slide it in the dry on the 175s if I'm trying...

have we answered the original question yet? ;) :p


Rob Armstrong

This thread was discussed between 16/02/2013 and 19/02/2013

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