Bias or radials? Please help this newbee!

[DavidA]

I am sure this has been addressed here many times, bit please bear with this newbee. I just acquired a 27000 mile original '59 Touring. It is my understanding that the original dealer replaced the factory tires with 560x14 Whitewalls when the car was delivered and that is what is on the car now. They are very badly cracked and must be replaced. I really want whitewalls again, even though I know they were never OE from the factory. I could get a new set of 560's but would rather have radials.

Now the questions ... 155 or 145 x14 radials and are radial tubes necessary or are the tubeless rims adequate for modern radials?

Am I going in the wrong direction with radials or should I stick with bias plys?

If I stick with the bias, is 560 x14 ok? That seems the only size available in whitewalls.

Thank you in advance.

[bmcecosse]

Welcome aboard - been in Nashville - many moons ago now!! Amazing to think of a Minor in Nashville.
You are v lucky if you can get hold of cross ply tyres in that size! The originals were 5.20 x 14. Most folks here use 145 x 14 radials, but I prefer the 155 x 14 although they are slightly too wide for the standard wheels. Radials do give a smoother ride and much better grip - but if you value the whitewall effect more than grip - go for it! Wheels are fine for tubeless - but do clean them up inside and of course fit new valves!

[Kevin]

I could get a new set of 560's but would rather have radials.

Hi David and welcome.
Most owners over here prefer the radials as they have better grip and handling on our poor roads and dont tend to follow road makings etc so much.
145's are the nearest we can get to the original 135's, the 155's can give a bit of a balloon effect and make things a little wobbly on the standard rims.

[Willie]

DAVIDA, Radials every time!. They hold the road better, run much more quietly, and last much longer too. All the other cars around you are running on radials so why put yourself at a disadvantage, especially in the wet! Radials are the single most effective change you can make to a Minor.

[minor_hickup]

I believe there are kits available to paint white walls on. Maybe google is worth a try?

[liammonty]

Radial tyres are definitely the way to go- my 1954 saloon's handling and ride was transformed when I got rid of the perished crossplies and put radial tyres on it. I fitted 155x14 (with tubes) and these are excellent, despite many people saying they're not! There's also a lot of talk about "original" 135x14, which I don't think is right- BLMC offered radials as an option in the late 1960's, and the tyres they fitted at the time were 145x14, so if anyone tells you they should be narrower, they shouldn't! 135mm is closer to the width of the crossplies, but these are not what were fitted! The other thing to remember is that the aspect ratio of these tyres is 80% of their width, so the narrower you go, the smaller the rolling radius of your wheel becomes. Crossplies (I think) had a 100% aspect ratio, hence they give the car's wheel arches a more 'filled' appearance than radials. So, fitting a very narrow radial will have the effect of 'gearing down' your already low-geared Minor due to the reduced rolling radius of the tyre. Go with 145x14 or 155x14 radials- you won't regret it!!

[Willie]

Liamonty, the correct radial size for the standard Minor rims is 145.
Indeed 145 is actually wider than the factory fit tyres fitted to the wider van wheels( 4 1/2J) whereas the standard Minor wheel is only 3 1/2" wide. If you are happy with 155 that is fine but that is not the correct size.

[liammonty]

Willie, indeed you're right, and I didn't say any different. As I said in the post to which you replied

"BLMC offered radials as an option in the late 1960's, and the tyres they fitted at the time were 145x14".

What I was getting at is that, just as 155x14 are not the correct option, nor are 135x14 (despite the fact that people on the messageboard seem to be very keen on them at the moment). Quite simple and we are agreeing with each other anyway, so there is no argument!

[rayofleamington]

Many Minors were sold with crossplies, and although BLMC may not have fitted 135's Radials, a massive amount of the owners did. The rolling radius of a 135 is slightly smaller than a 145, but the width is better for the rim - at nthe time they were probably cheaper too!

I expect BLMC didn't want to have 2 different speedo's due to the difference in rolling radius of the crossply and the 135, so used 145 as a compromise (although there's not a major difference).
155's are too wide for the standard rims and are outside of the manufacturers allowed range (a clued up insurance company could use this against you, although that's very unlikely)

Good 155's will out perform a bad tyre (e.g. old crossply!) so don't be surprised if someone who has never driven anything different likes them. That does not mean that 155's are a great choice, as 145's will perform better (unless comparing good new tyres with poor/old tyres).
The difference will be most apparent under heavy cornering and under normal driving won't be very obvious.

[Pyoor_Kate]

To answer the other question you can fit tubeless tyres, but some garages won't (at least; here they won't). *Most* of the original rims don't have the safety ridge on them for holding tubless tyres on should they suddenly deflate (say, if they were already fairly flat and you hit a kerb). According to my manual some of the very late rims do have this ridge (iirc).

Mine, as I recall, do not. But I said I didn't want tubes and after some argument the garage agreed to fit them tubeless - on the basis that tube'd tyres go flat fairly much instantly when punctured, wheras tubeless don't - and I'd rather go with that risk than the (as I see it) lower risk of kerbing it with flat tyres (since I'm fairly reasonable at checking tyre pressures regularly).

(and as a side point, my car's been shod with exclusively radials; 145 and 155. I had really shonky (kumho) 145's which were staggeringly out performed by some bridgestone 155s. The 155's were replaced with some crumby korean 155s which are no-where near as nice, so I'll try and get some decent 145's next time ).

[mike.perry]

For the last 30 years I have run my 52 Series MM on 155 x 14 Goodyear Grand Prix tubeless radials. The circumference is almost the same as crossplys so the gearing is not seriously affected. I figure that if you are short on acceleration you don't want to loose speed through the bends so I tend to corner on the door handles. Never had any problems with air loss or anything although I could feel the sidewalls flexing.
When Goodyears went out of production I fitted Firestone F60s. Just as good with stiffer sidewalls. Made the mistake of fitting a pair of Nankings to the front wheels. No directional stability, wandered all over the road.
Went back to Firestones all round. I run the tyres at 24psi all round.

[Willie]

That pressure seems a little low Mike, have you tried higher ones which would lessen some of the roll I suspect.

[minor_hickup]

Indeed, I ran my 155 radials at 30 up front and 29 at the rear. They wore very evenly.

[mike.perry]

My Morris Minor Series MM Operation Manual seventh edition, price 2/6 gives the correct tyre pressures as 22psi f/r. 24psi rear loaded. That was for cross plies which were 500x14 on the MM. The only other reference to tyre pressures I can find is 24psi front, 28psi rear stamped on the wheel arches of GPO vans, again for cross plies. I have therefore settled on 24psi front, 24psi rear for the saloon, 28psi rear for the van and 26psi rear for the traveller, being half way between. I will admit the Goodyear sidewalls did look a bit squashed but the Firestones do not look too bad.
Next question. I have recently fitted my traveller with 175x13s to cope with the extra power of the 1275. I am currently running them at 24/26psi F/R. I have not yet had the courage to find the limits of adhesion. Any suggestions for the best pressures?

[Willie]

I am using 145 s and, despite the factory recommended pressures for radials being
22 front and 24 rear I have settled at 26 front and 27 rear with no undue wear in the tread centres. I would have though that you would need at least these pressures using 155 due to the fact that they are a bit balloony on the small rims. Do your tyres not wear more quickly on the edges which would suggest under inflation?

[mike.perry]

The rear tyres wear evenly, the front tyres wear out on the edges due to these infernal road humps and width restrictions knocking the steering geometry to hell!!!!

[Willie]

OK I heard you the first time! If the fronts wear on both edges on each tyre then they are too soft. raise the pressure ( the rears should be at least the same and probably slightly higher). a side effect will be lighter steering effort too.

[mike.perry]

Sorry about the double entry. Anyone know how to do a delete???
I know a little bit about Morris Minors, a lot less about computers.

[bigginger]

Don't have a clue, sorry ;)
Andrew

[minor_hickup]

Why put more air in the rear tyres? I only did this to hoon sideways round roundabouts!

It's also worth noting that ther rolling radius of 145/80r14 is a fair amount smaller than 5.20x14 crossplies. i put them next to each other at work today as well as 155/80r14s. The 155 were the tiniest bit smaller also. Those crossplies have a very high aspect.