Care & Feeding of Knock-Off / On wheels

[Mike Drew]

Further word, this from Kirkham Motorsports (manufacturers of dead-on Cobra replicas; in fact Kirkham supplies the aluminum bodies to Shelby for his 'replicas'). There's a lot of good advice here; specific reference to the 'proper' direction for knock-off wheels appears partway down.

=====

Installing Knock-Offs/Spinners/Wingnuts

Since our cars use only one “lug nut” instead of five, you might think this is a simpler method of holding the wheel and tire on the car. While it is simpler in that there is only one part instead of five, there is only one point of failure so we need to use some extra caution when removing and installing knock-offs.

Tools needed:

Knock-off hammer or mallet
Traditionally these have been made of lead. We use a large (5 lb.) nylon mallet in the shop. Lead works well but does not last as long as nylon. We get our mallets at the local home builder supply place.

Safety wire and pliers
Safety wire is a must when properly installing knock-offs. Use 0.032 wire. A set of safety wire pliers will make the job of installing the safety wire easier. You can buy safety wire and pliers in kits from racing and aircraft supply stores (Aircraft Spruce and Specialty).

Anti-seize
This can be purchased at most automotive parts stores. If you don't use anti-seize, you will experience the following:

Best case: You will ruin the rim and the knock off with galling. It is highly unlikely you will stop at best case.

Worst, and most probable case: You will seize the nut onto the hub and you will experience all sorts of new words in your vocabulary as you CUT THE WHEEL, WING NUT, AND HUB apart to disassemble the whole mess. You will be left with mess on the floor and a big hole in your wallet to fix the mess. You MUST anti-seize the threads AND the face of the knock off where it contacts the wheel face. We even anti-seize the drive pins a little.

Jack
We use a low profile racing type hydraulic jack when we are away from the shop and don't have a lift available.

To remove knock-offs and wheels start with the car on the ground. We leave the car on the ground so that the force from removing the knock offs isn't transfered directly to the bearings. Remove the safety wire from the knock-off. Loosen the knock-offs by hitting them firmly with the hammer. Remember, the knock-offs on the left side (left as if you are sitting in the seats) of the car have right-hand threads; the knock-offs on the right-side of the car have left-hand threads. If you can get a good angle it helps to strike the knock-off on different wings. Once the knock-offs loosens you can then raise the car so that you can remove the wheel and tire.

Installing the wheel, tire and knock-off is basically a reverse of the removal, but it also requires some finesse. Start by applying a thin layer of anti-seize to the drive pins and threads on the hub. Place the wheel and tire on the hub by lining the wheel up with the drive pins and sliding it in place. Apply a thin coating of anti-seize to the threads on the knock-off and the area where the knock-off seats on the wheel. Start the knock-off onto the threads. Remember left-hand threads on the right, right-hand threads on the left. Tighten the knock-off until it starts to touch the wheel. Grab opposite edges of the tire and wiggle it side to side and up and down to ensure that it is seated on the hub and that the drive pins are engaged properly. Tighten the knock-off. Repeat until the knock-off is as tight as you can get by hand. You can give the knock-off a wack with the hammer to ensure that it is seated. Now you can lower the car to the ground and finish tightening the knock-off. To tighten the knock-off, strike the wing with the hammer. You should be able to feel the knock-off turn each time you strike it. When it is seated tightly the hammer will bounce back differently because the knock-off has stopped turning. It takes a little practice but eventually you will get a feel for this. Give it a few more wacks to ensure that it isn't moving anymore. You should not have to use “gorilla” force to tighten the knock-off. The drive pins transfer the force from acceleration and braking to the wheel, the knock-off holds the wheel against the hub.

Now it is time for the safety wire. There should be a hole in one wing of the knock-off. Run the safety wire from this hole to a spoke on your wheel. The wire should be installed in a direction so that it is holding the knock-off tight. This wire does not hold the knock-off in place but it is used to show that the knock-off has not come loose. Please bend ALL safety wire ends over to show you care and to prevent safety wire sized holes in your hands. Besides showing that you care, it looks cool. Never drive a car without the safety wire in place on all wheels. Checking the safety wire on each wheel should always be on your pre-flight checklist. Remove your wheels to clean your hubs and knock-offs and re-apply anti-seize once a year to prevent corrosion (more often if you live in a damp or salty ocean climate or if you use your car to trailer a boat).

=====

[Mike Drew]

Originally Posted by Russ Noble

After reading Jac Mac's post and the article he has scanned, I can see that I have got it wrong. For GT40 type centrelocks I now believe the rule is

RH thread on the RH side.

It is fortunate that I have found this out now, it would be embarrassing to have to strip the uprights and swap things over in the pits before I could race. Just goes to show how long helds views can sometimes turn out to be wrong....

Don't worry Russ--as amply demonstrated above (and you can spend eons doing Google searches of various Cobra and other knock-on-wheel-car forums etc. for further confirmation), your long-held views are right, and your car is correct as it currently sits. So instead of spending a bunch of time swapping your suspension components side-to-side to make it incorrect, you can instead devote that time to more productive pursuits--perhaps starting with a bottle or two of Lion Brown.

[Jac Mac]

I would love to agree with you Mike, if only there was one word in that whole page that told me 'WHY'.
I can see the logic in the Chapman example, and I could understand the example you have indicated if the wheel offset and/or camber setting were such that they cause the effective contact point to shift to the top half of the wheel/nut. ( Remember we are talking about what happens to the nut/spinner when the nut / wheel loosens slightly in service , this can be caused by different materials & expansion rates in the hub-nut-wheel assy along with deflection from lateral loads in corners etc )---- surely it would be desireable for the nut to self tighten when this happens.

Jac Mac

[Mike Drew]

I don't pretend to know the reasoning behind the manufacturer's choice, but (other than Lotus, which frankly has a rather hair-brained theory, methinks) they seem to universally apply the same standard. There must be some good reason for it?

(I forgot to mention that Ferrari also follows this standard, as do modern race cars; I was fortunate enough to blag my way into the pits at Le Mans this year, and I'm pretty sure all those cars also follow the convention).

About the only thing I can think of with a spinner is that if an object struck it while underway, with the standard scheme it would tend to tighten it, as opposed to loosening it. But that doesn't explain why modern race cars which use a giant hex nut instead of a tri-eared spinner still follow the convention. It can't be as simple as tradition, can it? There must be some science behind it?

[Russ Noble]

Originally Posted by Mike Drew

Don't worry Russ--as amply demonstrated above (and you can spend eons doing Google searches of various Cobra and other knock-on-wheel-car forums etc. for further confirmation), your long-held views are right, and your car is correct as it currently sits. So instead of spending a bunch of time swapping your suspension components side-to-side to make it incorrect, you can instead devote that time to more productive pursuits--perhaps starting with a bottle or two of Lion Brown.

Thanks Mike

I took your advice and spent all night consuming copious quantities of the Brown

Right now I just don't care if my wheels fall off or not

I would love to hear from Trevor Booth on this one. As a mechanical engineer and one who has been involved in centre lock wheel design he should be able to bring some definitive and relevant tech/physics to this thread.

Where are you Trevor?

Cheers,

BTW Mike, how do you know about NZ's best kept secret?

[Jac Mac]

You know, after thinking on this overnite the only logical reason to use the LHT/RHS-RHT/LHS is to avoid the self tightening feature when alloy wheels are used. With the steel wheels as indicated in the Elan example the wheel center will flex slightly & preload the nut as it is tightened. With the alloy wheel this wont happen to any large degree which explains the large torque figures being quoted for the spinner/nut. That is one other concern I have on this thread, please take into consideration - thread pitch, wheel/nut taper, and materials before using a suggested higher torque value. As Fran would say ''Apples for Apples".

Jac Mac

[Mike Drew]

Originally Posted by Russ Noble

Thanks Mike

I took your advice and spent all night consuming copious quantities of the Brown

BTW Mike, how do you know about NZ's best kept secret?

Well done mate!

I used to fly the Ice Mission, flying out of Christchurch down to the ice runway at McMurto Sound, Antarctica. I first discovered Christchurch in the early 90s, and quickly concluded that it was the single nicest place I'd ever been (and I've been everywhere!). I had some of the best fun of my life abusing the rental car I had, as the roads were beautiful, empty, and not a cop to be seen anywhere. I was also fortunate in that the weather was perfect the whole time!

Lion Brown was another wonderful treasure, and in fact we would load up the airplane with cases of the stuff to bring home. We would also buy huge quantaties of butter, and place it in the landing gear well, where it would freeze at altitude. A few bucks thrown to the guys running the chow hall in Hawaii would net us refrigerated overnight storage for the butter (no way we were trusting them with the beer though!), and the next day we'd reload it for the flight back home to California.

Nowadays, the only place I fly to is Iraq. Not much recreation or alcohol purchasing going on there though.

Although on my last trip, on the way home I got to stop by the Nurburgring and beat on an Alfa Romeo 156 rental car for a couple of hours.

[Bill Hara]

How about putting rht on all 4 corners and then wiring up to see what happens. In fact I am positive that all RF supplied spinners are identically threaded on all 4 corners. Pretty sure mine are...
I haven't looked at the physics of it so I won't comment other than to ask are we splitting hairs on thread direction?

Bill

[Russ Noble]

Originally Posted by jac mac

You know, after thinking on this overnite the only logical reason to use the LHT/RHS-RHT/LHS is to avoid the self tightening feature when alloy wheels are used. With the steel wheels as indicated in the Elan example the wheel center will flex slightly & preload the nut as it is tightened. With the alloy wheel this wont happen to any large degree which explains the large torque figures being quoted for the spinner/nut. That is one other concern I have on this thread, please take into consideration - thread pitch, wheel/nut taper, and materials before using a suggested higher torque value. As Fran would say ''Apples for Apples".

Jac Mac

Nothing like having a bob both ways Jac Mac!

Do you no longer give credence to the statement in your attachment that "it is known that at least one GT40 suffered in the 1970's from extreme wheel loosening problems because the hubs had been fitted on the wrong sides"?

"Avoiding self tightening" in actual fact means "promoting self loosening...." Not sure I would want to do that.

I also think that forty years down the track there may well be quite a few well intentioned souls who have decided that some tosser has put the hubs on the wrong sides on their original GT40's and so have swapped them back to the "traditional" MG/Jag/Triumph configuration. So even by referring to original cars we don't really know where we are then, do we?

Cheers

[Dalton]

This has been one incredible thread, on a subject you would think was sorted about 50 years ago. Very Interesting. I'm rather warming to five ordinary wheel nuts at this point, compared to all the anti-seize and wiring procedures, not to mention very large tools.

Dalton

[Mike Drew]

Originally Posted by Dalton

I'm rather warming to five ordinary wheel nuts at this point, compared to all the anti-seize and wiring procedures, not to mention very large tools.

Dalton

Philistine!

I've been happily living with knock-offs for ten years. Anti-seize, a big lead hammer, and safety-wire pliers are the only 'special' tools you need.

There are some cars (Cobras and GT40s among them) that just demand proper knock-offs.

[Jac Mac]

Pictures worth a thousand words. Now you only have to decide who was right-Ford or GM.
Personally I'm with Dalton, 5 studs are better than one and if I am the guy driving the car at 200mph then I will feel a lot safer for that!

[Scott Calabro]

Mike,

YOU ARE 100% CORRECT!

It would not matter if every car was different, and who cares if they are? The respective directions are self evident once you are actually performing the task. So is the direction of the safety. The torque could be different also. In other words always use the mfg.'s recommended torque's, grease and installation procedures.

If you go by the book you can't go wrong!



Cheers,
S

[Big-Foot]

Scott - Are you beating the dead horse as the official word from Tornado Sports Cars?


Here's the poop from Vintage Wheels;
:: Welcome To Vintage Wheels ::

Tri Wing Spinners
Tri wings to be torqued using a lead hammer of around 5lbs in weight and safety wired.
The safety wire must be pulling the spinner in the direction it tightens.
Adapters and tri wings are left and right hand thread; the RH thread is fitted to the left hand of the vehicle (looking forward from the rear of the vehicle)
A small amount of anti seize compound should be used on the mating surfaces of the wheel and the tri wing.

So with this, I'm convinced that it's a matter of personal preference as to which direction to tighten the spinner.

Now if we could get some corroborating information regarding tightness / torque..

Since we're talking about an alloy to alloy interface, I'm wondering if there's a rule of thumb that's similar to that of AN fittings where there is no specified "torque" rather a positional reference; Tighten until snug, then "1-more-flat of the nut".
Certainly not that 1/8 of a turn past snug would be "sufficient" for a wheel, but something on that order.. I'm also aware that the material and thread pitch would also play a role here.
For those of you that are racing your cars, I would think that this information would also benefit you as you remove and reinstall your wheels many times over in the course of a season. If you were to overtighten on a regular basis, you'll potentially brinnel or possibly displace the mating surfaces..

If you think I'm - please feel free to skip reading or posting..

If I didn't think this information was important (at least to me) - I wouldn't have asked for it..

Thanks!

[Scott Calabro]

Big Foot,

You asked a very good question when you posted this thread.

It can't be personal preference as to the tightening/loosening direction.

It is what it is, depending on how the direction the spindle mfg. cut the hub/spinner threads.

All I'm saying is, to follow your wheel mfg.'s recommended installation tech.

For you, I assume that is Vintage Wheels, so you can follow what is published on their website, and/or the info RCR provided you with.

As far as torque per degree of rotation, (AN fitting example) this is a function of thread pitch.

You are also correct, as I assume you have Aviation exp., that damage will occur due to deviation from published installation techniques.

You are not beating a dead horse.

Cheers,
S