Morris Minor Owners Club

Rob_Jennings wrote: What really is the difference in 145 155, given the car was specified to run on 145 is that the better option? I do find the 155's I have seem very spongy and a not very grippy on corners, I guess I should play with pressures on these before I change to see if I can get a better ride

Definitely try changing the pressures, I noticed a big improvement in going from 24 to 26psi in the front tyres (Nankan 155's).

I fitted 155's as 145's weren't readily available at the time. Now neither are but you can't mix them so it'll mean replacing all five if I change back and the two fronts are fairly new. I can see the argument about rolling on the narrow rim, maybe higher pressure helps counter that.

135's were much better than 145's on the cars I've tried and 155's seem to bring some vaugueness to the steering. Sadly, I cannot find 135/14/80 tyres anywhere

if you measure the crossplies, you will find out that 5.00x14 (standard spec) is 127 mm wide, I have got 5.20x14 (=132x14) tyres on my MM

So there is a point in saying that 135 would be better, but I doubt that at speed.
Onne

By better, I mean the feel of the steering. I'm not one to push my Minor to the limits of grip. And I like the look of narrow tyres. I'd alos like to try 125/14/80's if they were available.

So do I, but I tend to do quite a lot of motorways, and after all, it is the overall feeling that matters most

I fitted 155's as 145's weren't readily available at the time. Now neither are

Things have changed lately Bull Motif for one have tyres in 145,155 & 165 sizes.

But you can't argue that a wider tyre won't provide better grip and stability, even counting the extra movement/flex in the sidewalls.

I'd argue it also. A few people have changed from rubbish 145's to good 155's and preffered the result, but that's only to be expected.
The rims should have 135's but 145's will work ok.
To me, the large amount of ballooning caused by the 155 width feels like sitting on a space hopper - basically no sidewards stability. The effect of this when cornering hard (e.g. if you need to avoid some kid who stepped out into the road) is that the tyre lolls over and just the corner of the tread touches the road - very poor grip and high risk of loosing control at much lower speed than a narrower tyre.

The 155's are good on van rims though however those rims are approx 30% wider, hence suitable for a 155.


Like a few other people suggested on other threads - if 155's are ok for a 3.5" rim why do the tyre manufacturers refuse to recommend them and what would be the effect on your insurance in case of an accident? (hopefully the insurance company wouldn't spot the oversize tyres but that is what insurance assessors are for - to inspect the car as well as the damage).

Still the arguments go on. The factory do not arrive at tyes sizes by picking
them out of a hat, they do exhaustive testing! The standard Minor rims are,
as ChickenJohn suggests suited to 135X14 Radials this will be close to 'as
specified' and will retain the famously light steering of the Minor and you will
certainly never suffer from aquaplaning! The 145X14 still suits the standard
rims without bulging too much at the sidewalls and,as I have pointed out before, the 145's are WIDER than the factory fitted tyres on the LP917 wide
van wheels. I am running 145's on my LP917's and there was a noticeable
improvement when these same tyres were tranferred from my standard Minor wheels due to the fact that the sidewalls do not bulge at all! If you
have 155's fitted try standing at the side of the car and pushing it...the car
will wobble unless you have a rather high pressure.

Some information about my tyres (all 155s). I've just replaced a Firestone on the o/s rear which lasted 7 years and about 21,000 miles. Both front tyres (Chinese brand, Nankang I think) are 4 & 5 years old and both have worn quite badly on the outside edge (I normally have them at 26psi). The new (Chinese) tyre seems to bulge more than the Firestone ever did. I was told that 15,000 miles isn't a bad mileage for these cheaper Chinese tyres....

I was told that 15,000 miles isn't a bad mileage for these cheaper Chinese tyres....

Blimey thats not much is it, I know modern cars are heavy on the fronts due to power steering ect but on the moggie I would have expected quite a bit more......

I was chatting to a bloke who works for BA Engineering recently who saw me drive my mog into the staff car park. He used to have a Minor in the 60s and reckoned the old crossplys would do well over 50,000 miles with a Minor....

If the tyres are worn on the edges - it's because your pressures are too low. I use 30 psi all round on 155 - works well for me. Of course I would prefer the wider rims - if anyone has some for sale - let me know please.

CHRIS, If your tyres have worn on the front on one edge only then I think
you either have misaligned front wheels or you live on a mountainside! The edge which wears indicates too much toe-in or toe-out but I don't know which
is which, stand by for the answers to pour in!!

Yes, the tracking was well out on one front wheel - it was a bit of a struggle but I eventually got the garage to set both to a slight toe-in. As for the pressures, I've been running 26 psi for the last year. I may try 28psi again but I always found that this pressure made the front end a bit too light. I think it's been a combination of both factors.

edge which wears indicates too much toe-in or toe-out but I don't know which
is which, stand by for the answers to pour in!!

If they are worn on the inside, there is too much toe out. If they are worn on the outside there is too much toe in.

As for 'the tracking being out on one wheel' that is a misnoma. The tracking adjustment affects both wheels equally.
If you adjust one side only it will affect the straight ahead position of the steering wheel, if you adjust both sides it won't affect the steering wheel position, therefore if one side was adjusted it should have been to centralise the steering wheel (or done by a cowboy, leaving the steering wheel wonky).

if anyone is after old sizes (135's etc.) these guys may have them

http://www.vintagetyres.com/

Rupert

doobry wrote:If they are worn on the inside, there is too much toe out. If they are worn on the outside there is too much toe in.

Yep.

/ \ is toe in, and you can see the outer edges are going to be scrubbing as they're "leading".

\ / is toe out, where the inner edges are "leading" and so scrubbing.

As for 'the tracking being out on one wheel' that is a misnoma. The tracking adjustment affects both wheels equally.
If you adjust one side only it will affect the straight ahead position of the steering wheel, if you adjust both sides it won't affect the steering wheel position, therefore if one side was adjusted it should have been to centralise the steering wheel (or done by a cowboy, leaving the steering wheel wonky).

Agreed to an extent on steering angles, but another effect of only adjusting one side is the reduced amount of steerign arm after the balljoint in the rack. This can play hell when going over bumps, and other than lazy cowboy practices there's no reason for it!

Out of interest is there an easy way to check the aliment and castor angle of the front wheels? All the garages i've taken it to wont even check them. i have new nangkag things as they were the cheapest, why pay big money when your limited to 3000 miles a year? No complents so far.

There is a gadget on the market for D.I.Y. purposes that is a drive over item for checking tracking or you can make your own via the bearmore`s excellent site
http://www.beardmorebros.co.uk/website% ... acking.htm

Thanks for that just curious will have a go at it sometime.