Spigot Rings Fitted Now Totally Confused

[New Forest Terrier]

I posted a couple of weeks ago about how my Bongo suddenly lost all wheel balance over 60mph following the replacment of front brake pads. The situation was diagnosed by Micheldever Tyre Services - Local Specialist and Discount Tucks as missing spigot rings.

I unfairly blamed my local garage who did the MOT and brake pads for the problem and to sort it out obtained a new set of spigot rings which were finally fitted today. Once the wheels were off there were no spigot rings on the back wheels either.

Looks like none were ever fitted. But adding them has solved the problem. Bongo road tested on M3, perfect at all legal speeds and even several illegal ones.

What is the answer Why can a Bongo which ran perfectly on aftermarket wheels without spigot rings, sudenly run if as though its on cobbles just because the wheels have come off and on

Only possible explanation put forward so far by the guy who fitted the rings is that the Bongo has chamfered wheel nuts which stop the oversized wheels from damaging the wheel studs. Is the explanation and if so how?

My only contact with chamfered nuts was when I owned an old horsebox made from a commer van with wheels fitted using them. Fine until someone changed a puncture in a gale and put the nuts back the wrong way, Result two sheared studs and a morning spent combing scrappies for a commer wheel hub,

I am sure somene can provide an explantion. IEven if not I am just pleased all is finally sorted out,

See you at the Bash on Thursday

Terrier

[kev&caz]

Why can a Bongo which ran perfectly on aftermarket wheels without spigot rings.
This was more by luck than judgment.
If the bore in the wheel is larger than the diameter of the wheel hub spigot the wheel can move off set to the hub. This will give the effect of the wheel being elliptical thus not running true to the hub. Imagine a line running through the centre of the axel and one wheel is below the centre line and the wheel on the other side is above the centre line this will exaggerate the problem. This can cause the 5 stud holes to fret (ware) and become larger in diameter thus making the problem worse ( If aluminium soft material studs minimum of EN?(8) a harder material). This will eventually cause a failure of wheel or studs. Or the bore of the wheel will become so big along with 5 stud holes the wheel will fail. If you have the bore held firm on the spigot this will keep the wheel central to the hub. The taper on the wheel nuts will take up any minor discrepancy thus all will run true to the centre of the axel. It’s been a long time since I’ve done any engineering explanations but give me a fag packet (no I don’t smoke given up nearly two years) and I can sketch what I mean. Hope this helps?
See you Thurday
ATB
Kev

[dandywarhol]

The reason for the taper is to take the load of the vehicle! If the taper in the wheels and taper on the nuts aren't the same no amount of spigots will sort the problem permanently.

If they're aftermarket wheels with worn or damaged mounting holes then SCRAP them before the studs shear off and you career into something/someone!

any pics of the wheel setup?

[BongoMTBer]

Before I had fitted the spigot rings on mine, to centralise the wheel, I had success in centralising the wheel by first finger tightening all the nuts, and the slowly working my way around with the torque wrench and incrementally increasing until the correct torque was achieved. This gave a good result in terms of centralising the wheel and is the way you should do up your wheel nuts anyway.

In my experience, garages/tyre fitters don’t normally do it this way, just using the windy gun and if you are lucky a torque wrench at the end. This is why I always reset my wheels when I get home after someone else has had the wheels off.

Unless there is evidence of significant ovalising and/or non-uniform fretting within the chamfers of the rim bolt holes, tightening correctly with the spigot rings fitted you should be perfectly safe. If in any doubt, periodically check your wheel nuts regularly until you confidence is regained.