Wheel spacers

Started by alfa duk, July 08, 2012, 05:47:24 PM

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alfa duk

 I drove this car  for the first time last weekend at a race meeting and on the first outing, it had more vibration than what i would expect so i put a new set of boots on and the vibration improved to an acceptable level but was still there. I was going over the car today and decided to pull the wheels off to check and noticed that the wheel spacers are not exactly round- you can feel it against the hub and then found that the wheel has the wrong size hole for the hub. Now this is not that much of a concern as when you add spacers the wheel no longer centres on the hub but as i always do when making spacers, you machine them with a hub centre. This leeds me to the question, without the hub centreing the wheel, is it possible that the wheel gets fixed to the hub off centre as only the studs are used to locate it. Could this be an issue or do most racers use a standard flat spacer without vibration issues?
85 gtv6 dead, cant let go
84 gtv6 24 valve VRA spec
84 gtv6 andalusia
80 gtv group s

Neil Choi

#1
Alfa duk

You are correct, you need to locate the wheel on the hub centre in order to avoid the vibration.  So the spacers will need to be, as you say, machined with a hub centre.

Awhile back when doing a basic modification to front brakes with different calipers and discs, my Simmons wheels would rub the calipers, so spacers were used to clear it, the wheel was off the hub centre, and vibration appeared, careful tightening of wheel bolts only eliminated vibration slightly.  So concluded the wheel was not sitting 100% centred, ie not on hub.

So hub centres are needed.  Then again, I could be wrong and this is nothing new.  In fact I think there was a discussion on hub centricity already.

Neil

colcol

Spigots locate, bolts and nuts clamps, bolts and nuts don't locate, remember this when your car is sitting on its roof, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

MD

Never had any success on Alfas without centering on hubs. A communicative suspension like Alfas have will convey centering errors (and balance) more readily so accuracy is paramount.
Transaxle Alfas Haul More Arse.

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colcol

There is about '05mm to '00mm clearance between the hub spigot and the bore of the wheel, this will locate the wheel good, when you put the bolts or nuts on, there will be some movement to allow the fasteners to tighten / loosen, if the wheel is not located on a spigot, the bolts will loosen off and you will end up on your roof, the taper on the nut / wheel is not to locate the wheel, it is to add friction between the fastener and the wheel, to stop the fastener loosening off, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

colcol

If the wheel is not located on a spigot, then the wheel will move up and down, because it hasn't got anyway of holding it central, thats why all car manufacturers use central locating spigots, to locate the wheel accurately, the fasteners 'clamp' the wheel to the hub, thats why important things like flywheels, clutches, cylinder heads, etc have dowells to locate the part accurately, and fasteners to clamp the parts together, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

alfa duk

 Thanks guys, you confirmed my suspicions. Bet this got some people thinking about their own set up
85 gtv6 dead, cant let go
84 gtv6 24 valve VRA spec
84 gtv6 andalusia
80 gtv group s

scott.venables

Definitely good to have a spigot to locate the wheel so it does not run out and cause vibration.  The wheel won't fall off because you don't have a spigot.

Minis don't have a spigot at all, just the wheel nuts in the tapers in the wheel, and you hardly ever see Minis on their roofs.

colcol

No, when a Mini has a wheel fall off, it understeers into the nearest tree, seriously, whatever setup you have, make sure its safe, as it can all go wrong in a split second, car makers put spigots there for a good reason, Mini's have a 10 inch wheel?, so there would be less mechanical advantage in trying to loosen the wheel off, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

morgancooper

Yeah, I will also say that these rules also apply to initial gear shift of drifting. Alfa suspension never worked for me, still in confusion to figure out the technical glitch.

Duk

Only ever use 'hub centric ' spacers (spacers that have locating spigots)!
Locating the wheel is obviously important from a vibration perspective, but the central spigot is the part that transfers the bump force from the wheel to the wheel hub. I've seen a few cars loose their wheels from the shock loading of bumps eventually snapping the wheel studs.
Car manufacturers and heavy industry do it for a reason.
If you suggest otherwise, sorry, but you are just plain wrong. And just 'cause Mini's didn't use them certainly doesn't make it right.

aggie57

Quote from: Duk on October 04, 2012, 05:48:52 PM
Only ever use 'hub centric ' spacers (spacers that have locating spigots)!
Locating the wheel is obviously important from a vibration perspective, but the central spigot is the part that transfers the bump force from the wheel to the wheel hub. I've seen a few cars loose their wheels from the shock loading of bumps eventually snapping the wheel studs.
Car manufacturers and heavy industry do it for a reason.
If you suggest otherwise, sorry, but you are just plain wrong. And just 'cause Mini's didn't use them certainly doesn't make it right.

NO DUK!  The spigot locates only.  It does not transfer any load.  The hub and wheel, once the bolts / nuts are properly tightened, act as one unit and carry all the loads.  Once I thought the same as you......
Alister
14 Alfa's since 1977. 
Currently 1973 GTV 2000, 2020 911 C2S MT, 2021 Mercedes GLE350, 2023 Polestar 2 LRDM
Gone......far too many to list

Evan Bottcher

I was looking at these spacers: http://www.serpentautosport.com/HTML/Hub%20Adapters%20and%20Spacers.html

Specifically the adapter-style that you fix to the hub (see picture).

Any other recommendations for suppliers?  Probably need to be made to order, and exact spigot size, PCD, and spacer width.

Newest to oldest:
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Evan Bottcher

OMG I just posted in the "Racing > Rear Wheel Drive" section.  Blasphemy.  Washing my mouth out!
Newest to oldest:
'13 Alfa Mito QV
'77 Alfasud Ti
'74 Alfasud Sedan
'68 1750 GTV
--> Slow and Fun - my Alfa journal

Neil Choi

Evan

Remember, you have crossed to the darkside, you are a racer now and there is no turning back.

Neil