Morris Minor Owners Club

I had assumed that the car in question was a 1098cc Minor 1000 so I have quoted the tyre size originally recommended for that model: 520x14 or 145x14 radial.
Although you seem to feel that the Morris Minor is fitted with tyres that are too big, it is not the only car built by BMC which used that same wheel. The Wolseley 1500 and Riley 1.5 did, and the recommended size of tyre for that car was wider still. A 560x14.
I'm sure you are aware that the tyre width is not measured at the point where it fits to the wheel but, so to imply that it does and that many Minor owners are fitting wildly incorrect tyres is somewhat misleading.
Wider wheels might look good on a Morris Minor and they are quite popular but are certainly not necessary!

I had assumed that the car in question was a 1098cc Minor 1000 so I have quoted the tyre size originally recommended for that model: 520x14 or 145x14 radial.
Although you seem to feel that the Morris Minor is fitted with tyres that are too big, it is not the only car built by BMC which used that same wheel. The Wolseley 1500 and Riley 1.5 did, and the recommended size of tyre for that car was wider still. A 560x14.
I'm sure you are aware that the tyre width is not measured at the point where it fits to the wheel, so to imply that it does and that many Minor owners are fitting wildly incorrect tyres is somewhat misleading.
Wider wheels might look good on a Morris Minor and they are quite popular but are certainly not necessary!
Picture below taken from Wolseley 1500 Owner's Handbook.
[frame][/frame]

Haven't we done all this before? I've not heard of any disasters arising from folks using the usual type sizes that are around now.

SteveClem wrote:Haven't we done all this before? I've not heard of any disasters arising from folks using the usual type sizes that are around now.

Quite, but still the jelly and blancmange has to be brought out......Sounds like quite a good party tea doesn't it!

What flavours have you got, I prefer strawberry and blackcurrant.

amgrave wrote:What flavours have you got, I prefer strawberry and blackcurrant.

I prefer lime, but blackcurrant looks the most like tyres, so best go for that, in 155 mm circular jelly mould. Oh, wait, should that be 145mm?

I used to MAKE tyres, just at the time of conversion from crossply to radial. The Michelin X was of course way ahead of it's time. (I made UniRoyals - or at least I engineered the machines that cured the tyres, but was through the whole factory as part of the training course). The '145' mm refers to the tread width - as does the 5.20" of course. And I will admit to using 5.90 x 14 crossplies on my rally Minor many moons ago.....there was nothing else. But radials are a different proposition, with much more squishy side walls and if you refer to any tyre/rim chart today you won't find anything like a ratio of 6" wide tread on a 3" wide wheel....especially a wheel with no bead retainers !!! Some tyre places refuse to fit tyres that are outside the rim width chart guides - for fear of liability in the event of an incident.. But I know many do find the 155 tyre ok - it's just so much better when fitted to a wider wheel!

bmcecosse wrote:I used to MAKE tyres, The '145' mm refers to the tread width - as does the 5.20" of course.

Perhaps it was a long time ago and you have forgotten how tyres are measured? The tyre width, 145 for example, is the "section width" not the "tread width" which is much less. In cross section of course, an inflated tyre is shaped a little like a balloon. The tyre width or section width is the measurement across the tyre from sidewall to sidewall at the widest point.

If you measure across the contact tread on either a Bridgestone 145x14 or a Nankang 155x14 the tread width is only just over 100mm. There is almost nothing between the tread width of these two popular tyres despite the different nominal section widths. The difference can be measured in their section width - about halfway down the sidewall.

Tyres are not the easiest things to measure and I have not done it very accurately or scientifically but our two Morris Minors are shod respectively with these two makes/sizes so provide a useful comparison.

Picture shows a 155x14 Nankang tyre.[frame][/frame]

Thread resurrection!

My rear suspension continues to squeak, knock and jiggle on the rebound. Bushes are easy enough to change but would others agree my dampers are likely knackered? I have tried refilling dampers with SAE40 but I think it's leaked out again.

Would like opinions before I part with cash.

Bounce test: https://youtu.be/b1C3-AQ4yrY

I find that my opinion on the Morris suspension varies,depending upon what I drove previously.
The traveller certainly feels better with a bit of weight in the back. And the strange noises disappear too.

''Knackered'' can be quite subjective when referring to repairable/reconditionable items.

They certainly need attention if leaking oil quite quickly, but it is not the end of the world....

It's not the end of the world, no, but the ride is rather uncomfortable with the clunks and hopping at the rear!

Have you tried bouncing the car with the dampers dis-connected, the noises could be coming from dry spring eye bushes.

The YouTube 'bounce test' only showed the tyre, so does not really tell anything about the rest of the suspension. Rubber has a high degree of hysteretic damping, so will naturally return quickly to a steady state.

Can you show the car itself being 'bounced'?

Pathe Films Archieve Testing Morris Cars - shews side to side movement but not up and down ( unless test not shown properly)
https://www.youtube.com/watch?v=nV4GyENUDfI


BMC (Austin Cambridge and A40 c1959) testing , some vertical body pitch https://www.youtube.com/watch?v=nuwTWujeMM0

Just to bring this thread to a conclusion - I'm pretty damn sure as least one damper has had it as it's leaking oil. May try ESM's "30% uprated" ones when the budget allows.

I have now replaced the wheels with the wider van wheels and replaced the dampers (with SAE30 oil in). The damper link to chassis bushes are now poly too. The issue is reduced but still present during deceleration (lifting off, no brakes) and acceleration. Deceleration isn't helped by the diff backlash I suppose.

Next I will be replacing the spring pads with poly ones and failing that fitting radius arms!

Are you sure your "U" bolts are properly tight? If not, that can have an effect. I haven't gone back over the whole thread but I expect you fitted poly bushes to the rear springs previously did you?

don't know how I missed this first time round,but I had the same issue after fitting new leaf springs,changed bushes and pads and still had a bouncy rear,not the sort you get with no damper effect,but just a feeling in the rear . On static bouncing I could see that the slight bounce was mainly from the tyre wall compressing (Nankings as above) ,there was little if any movement on the springs,came to the conclusion that the new springs were over tempered. Took the small lower leaf off and instantly cured the bounce.When I sold the car gave the leaf to the new owner and when I saw him about two years later ,he said he had put the leaf back on after several thousand miles and all was now ok. So suspect that the new springs are just a bit too hard and need to soften with use.

Interesting kennatt, thanks. If the poly spring pads don't make a difference I'll look at that. I do much prefer a soft rear , and it doesn't do any harm on a RWD car either!