Richard,
I don't know but I couldn't dismiss the load bearing at the hub centre completely. I can't remember exactly but there is a problem with swapping alloys/wheels from different vehicles in the Land Rover range as some were designed for wheel centre load bearing and others for the studs to take it all.
If the centre isn't designed to share the load why do many wheels fit so closely to the hubs? As the wheel nuts/bolts have a tapered seat it should be possible to do away with the fit so tight they rust on....but they keep doing it.
David
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That would have to be an LJKS article.
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Richard
Are you a reader of 'Car'?
Oddly, I was recalling an article by the same gentleman, who was attempting to buy alloys for his Honda many years ago, and went to great efforts to get a set of wheels which accurately fitted the centre spigot! He was complaining about efforts to sell him wheels which sported a larger than required centre hole, thus leaving all location to the studs.
Yes, I agree that the wheel bolts should achieve sufficient clamping force to prevent movement of the wheels, and the centre spigot should only act as a centring device. The studs should not be a tight fit in the holes, but should be centred by the tapered seats of the nuts, and/or by the spigot. All these factors are important. Older cars probably survived because cornering forces and wheel loadings were somewhat lower.
Under cornering there is a degree of distortion of the wheel centre as the wheel is loaded. This is why poorly fitted hub caps usually disappear on corners.
Aluminium alloys behave differently under load than steel. They don't display a clear elastic limit, and even a high strength Al alloy has an Ultimate Tensile Strength well below even the elastic limit of a mid range steel. Size for size Al alloys exhibit greater deflection for a given load. In some ways not an ideal wheel material, and as has been mentioned, unless of high quality, unlikely to display any great weight saving. This all means that unless alloy wheels are properly designed the distortion in service will be greater than in the steel wheels. Because of the increase propensity for distortion, the clamping load of the wheel studs will be critical. No doubt recognising this, some carmakers specify a greater wheel bolt torque for alloy wheels compared to the steel wheels.
A properly sized wheel will have the close fit on the spigot, and this will tend to limit movement in this crucial area, should the design of the wheel be marginal causing excessive distortion of the wheel centre. This extra restraint will be absent if a plastic spacer is used, as this will only centre the wheel during installation. Therefore it's feasible that a combination of marginal wheel design combined with a lack of support at the spigot could lead to problems, and in any case the centre spigot provides some extra security if the wheels are subject to high loadings.
Regards
John
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John
I've posted before that many of my experiences with Morris Minors have been poor or scary. Here's one...
About 25 years ago I "borrowed" an elderly Minor from a chap at work for a month or two while I was "between" cars. Showing off one night with GF (now Madame) aboard, I came in to the pub car briskly and completely botched a handbrake turn. The car slid sideways into the kerb, the right front taking the brunt of my abuse. A loud metallic crack was heard, which I put down to the hubcap coming off.
Days later I was on my way to a job out of Leeds on the M621 when I was overtaken by a wheel.
"Some poor sod has lost a wheel" thought I, as the car settled onto the brake drum.
The wheel was retrieved with a roughly rectangular hole connecting the wheel nut holes and the corresponding piece was still attached to the drum by 4 nuts.
I put the spare on and bought another wheel and hub cap from a scrappie that weekend.
Just about on topic.
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Kindred spirits Darcy.
Once lost a wheel from the rear of my Herald while flat out round a corner. I had wide tyres and those wheel spacers with stud extenders. The load was just too great and the threads stripped.
The wheel was the rear outer under load on a 40mph corner. Amazingly the brake drum and chassis hit the road with a bang but there was little change in cornering the line.
Bloke came out of his house nearby but I waved him away with a casual "OK mate, only the back wheel fallen off". Jacked it up, re-fitted the wheel and home with a bit more care until I fitted new wheel studs.
Long term resolution was to fit some 5.5Js made specifically for the car with 175 tyres and then I could lose the spacers.
With that 1147cc (?) engine you *really* needed big tyres.
David
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Darcy
Was that an early Minor (ie pre Minor 1000)? I believe for the 1000 the wheels were 'beefed up' including thicker material for the centres! Bit late to save face now, but it could be a partial explanation!
As for David, yes, we all remember wheel spacers. No self respecting boy racer was complete without a set, although most graduated to a set of 'proper' wide wheels. On the other hand there was a chap I knew who stuck for cash simply bolted the wheels on inside out. Luckily the overhang was so great he was forced to reverse this decision fairly rapidly.
My worst event was also when out with the 'GF, now wife' in my Mk1 Cortina. (originally a 1200 DL, I fitted the big valve 1500 GT engine, 3.77 lotus diff, lowered suspension, 5 1/2 J's, extra instruments etc. You get the picture) I'd been a bit concerned that one rear corner of the car was looking a little lower than usual, but you know what they say - if it don't scrape, it aint low!
Driving over a bump in the road, the said corner emitted a bit of a thump and settled on the bump stops. The leaf spring had broken, luckily just behind the axle. So, staggered home to GF's house at much reduced pace. Then there was the time the fuel line came of the carb on the motorway and showered the engine bay in fuel........
Happy Days
Regards
John
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John,
I'm not a Minor expert, but it didn't say "1000" on the bodywork anywhere. This was the car that I took from Leeds to Hull in a snowstorm and where I learned a little about management technique as follows;
Scene; offices in Seacroft, Leeds, complete white-out, 3 inches of snow on the ground. Australian hard-case manager enters.
Manager "Darcy, I need you to go to XXXX in Hull, right now, here's your fault report"
Me "But, Rufus, it's snowing"
Manager theatrically raises eyebrows and walks over to window and presses face against glass with some irony.
"Correct. Were you planning to drive home tonight?"
Me "Yes", thinking of the 4 mile journey to Leeds.
Manager "If you can drive home, you can drive to Hull. Now get going you lippy Pommie b*st*rd before I change my mind and swap this fault report for your P45"
And the Minor fish-tailed its way through the snow to Hull and back again.
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Darcy
What we call a Graduate of the JFDI(*) School of Management
regards
john
(*) Just Flipping Do It (No, hang on, I don't think I have the second word correct. Umm......
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If it didn't say 1000 on the bodywork, it was an early one. Gosh, nearly forgot the motoring link.
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John S wrote:
> Aluminium alloys behave differently under load than steel.
> In
> some ways not an ideal wheel material, etc etc etc
Thanks for that, John S.
I feel this is a very important point, especially as there now seem to be a proliferation of alloy-wheel refurbishment places, specialising in fixing buckled wheels.
I don't think I'd trust a wheel which has been kerbed badly, and them knocked/bent/welded/patch back into shape.
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Ian, excellent point. Absolutely not to be trusted. If you need work done, which doesn't involve damage eg refinishing, ensure it's done on your wheels, and don't take exchange units!
Regards
John
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