21 replies to this topic

[ls2lxhatch]

A link to plastic adaptors available from JEGS was posted by Litre8 another thread on the subject. They have a 70.3 mm/82 mm adaptor. Dragway will make them, not sure about the price.

Maybe cheaper here

[Struggler]

Most tyre and wheel outlets will have stock, try a Bob Jane or similar.

[StephenSLR]

I had my BMW wheels fitted at Bob Jane today, the guy was telling me how the centre bores may not be the same as Commo.

I asked if there was any issue with that, he said at high speed I may feel vibration. I went ahead and had them fitted.

Still concerned I checked the web and saw this:
Broken wheel studs - why spigot / hub rings are so important with aftermarket wheels

A little bit pissed of with the lack or care from Bob so I rang around, Tempe Tyres had hub rings.

For the BMW wheel I have on Commo stub the ring is size 69.6/72.6 (i.d/o.d)

I had them fitted they're hard plastic and I'm not the most confident. At the front I think they'll be ok as the hub stick out far but at the rear the spigot is very slim and just stops short of the centre bore, the ring is locating it all right but with heat and bumps in the road, etc. I fear it could crack.

With the rear wheel there is a larger bore before the centre bore, I'm thinking if I can get a ring to fit the larger bore then slip the smaller ring in that it should be ok... or just get a larger outer diameter ring.

Does anyone know who stocks or makes metal hub rings?

s

[ls2lxhatch]

Remember the wheel nuts are simply there to hold the wheel on, NOT support the weight of the car. Also, as there is nothing to centre the wheel, you'll notice the wheels go in and out of balance because as you drive around, they'll move around on the hub

The above quote is wrong.

The sole purpose of the hub locater is to help centre the wheel on the hub, the final alignment of the rim to the hub is achieved by the wheel nuts. The hub locator can not and does not take any load once the nuts are tight as a result many aftermarket hub adaptor rings are made of plastic.

The factory wheels are a loose fit on the factory hub. If the hub was designed to take load then the hub and rim would have to be a taper or press fit.

If you are still not convinced then have a look at the setup on a car with factory wheels or give Dragway a call.

Edited by ls2lxhatch, 18 February 2011 - 05:30 PM.

[StephenSLR]

The above quote is wrong.

I think so too, the nuts definitely bear weight, I think that's obvious.

From what I've been reading it seems the locator may stop the hub from moving too far in any direction at high speed reducing the chance for vibration.

The hub from my Commo stockies are a very snug fit, the guy at Bob's called it an interference fit.

I've had the wheel nuts from a rear mag wheel shear on me before, it felt like the car had a flat, it was getting wobbly so I pulled over. The wheel looked a little askew and the wheel nuts came off in my hand - all of them sheared. I was lucky I pulled over in time - sheesh, the trouble it could've caused! So as you can see I already have an inbuilt fear of it happening again.

I have a feeling there was some foul play, I think someone at the last place I visited loosened them. There was this insurance ad at the time where the bloke yells 'the wheel nuts!' and we were making fun of that ad that day so it's almost certain there was some smart arse who thought he'd make more of a joke out of it.

s

Edited by StephenSLR, 18 February 2011 - 05:44 PM.

[StephenSLR]

I think I get it now.

After doing more reading it seems with the hub ring the mechanic can fasten the wheel so it's bang on centre, without it the wheel can be slightly off centre and this is what causes the vibrations - right?

s

[76lxhatch]

^ Spot on. Your plastic locators will be fine as long as you don't damage them when you take the wheels on and off. ROH wheels are common fitment to both BMWs and Commodores and normally have an alloy ring, maybe they make them if you still don't like plastic?

[ls2lxhatch]

Correct.

If there is no hub ring but you take care fitting the wheel nuts then you should still be able to get the wheel centred as wheel nuts finish the alignment job.

If there is no hub ring and you are careless fitting the wheel nuts then the you could end up with the wheel off centre resulting in vibration and possible stud failure.

[rexy]

To be honest this is a largely theoretical problem only.
Unless you have an underlying issue such as malpositioned studs, worn or malformed wheel nut holes or badly worn wheel fasteners you will locate the wheel correctly every single time.
No need to lose much sleep over this issue.

Edited by rexy, 20 February 2011 - 02:33 PM.

[Litre8]

Not so sure on the studs bearing the weight.

My understanding is that correctly tensioned studs should only be applying force to hold the wheel face against the hub face (ie along the stud centreline). That compression force will bear the weight unless the studs are not tensioned correctly.

[StephenSLR]

Not so sure on the studs bearing the weight.

My understanding is that correctly tensioned studs should only be applying force to hold the wheel face against the hub face (ie along the stud centreline). That compression force will bear the weight unless the studs are not tensioned correctly.

That makes sense as studs are meant to take force along centreline and not perpendicular.

The stud also doesn't sit on the hole edge but float through the centre, the nut however does sit on the hole so if there is any slippage the stud will have a bending moment where it meets the hub.

With 5 studs and friction between the flat mating surfaces of hub and wheel you'd hope all that would be enough to secure against slippage.

s

[rodomo]

To be honest this is a largely theoretical problem only.
Unless you have an underlying issue such as malpositioned studs, worn or malformed wheel nut holes or badly worn wheel fasteners you will locate the wheel correctly every single time.
No need to lose much sleep over this issue.

I don't think you've experienced the problem?

[rexy]

I always use well made gear in good condition. Never had the problem referred to in this thread.
You would have to have significant slop or background manufacturing errors for this to occur.

[StephenSLR]

How about the tensioning order?

I've seen some tighten the nuts in circular order rather than opposing order.

s

[76lxhatch]

Using the correct tightening sequence certainly doesn't hurt, just another handy method of ensuring that everything works as intended

[StephenSLR]

Using the correct tightening sequence certainly doesn't hurt, just another handy method of ensuring that everything works as intended

I used to work in injection moulding and the injector had at least ten Allen bolts, if you didn't tighten them in opposing order you couldn't get the thing on.

I found that out the hard way trying to take a short cut with it, as I was undoing it to start again and do it properly my supervisor said, you kids don't have enough time to do things once but always have enough time to do it twice.

s

Edited by StephenSLR, 20 February 2011 - 07:06 PM.

[Stinga]

i got my hub locaters off ebay, there was plenty of different sizes available when i was looking

[rodomo]

I always use well made gear in good condition. Never had the problem referred to in this thread.
You would have to have significant slop or background manufacturing errors for this to occur.

That's why they make hub locaters.

[StephenSLR]

That's why they make hub locaters.

I found a good description on ebay saying they ensure the fitment is hubcentric instead of lugcentric.

This was something I hadn't thought of, that the lug PCD may not be concentric to the wheel but if the wheel is that poorly designed who's to say the hub would be any better located?

s

[StephenSLR]

the lugs were off center when you did up the nuts you would be bending studs?

I'd say so.

s