Care & Feeding of Knock-Off / On wheels

[John Owen]

If the spinner is adequately tight, it does not matter which way the threads run, the pins transmit all torsional load and much of the transverse load. If the spinner is loose, the the situation will degrade regardless of thread direction. However, if you encounter road trash, particularly when spinners were hung out in the wind, it was and is very important to have an impact tighten rather than loosen the spinner.
As to antisieze, it is great and should be used. However, it is still possible to overtighten with an enthusiastic hammer, firsthand experience. I have a vague recollection of 300 ft-lb being the required torque, but that needs to be verified. I will build a wrench with a long arm for my use in the future.
In my opinion, safety wire on spinners is just a reference - I have seen heavy wire stretched by a loose nut. Consider it an indictor of problems. I use a light wire and check often for slack.

 

[Malcolm]

On my Prosport with centre lock wheels, I use 280 lbs/ft torque. I have a big torque wrench just for this purpose.

 

[Martin]

Finish Line Accessories used to do a tool. My link to their website doesn't work anymore but i kept a photo of the tool. I don't have anymore info on it as I didn't purchase one but thought it may be of interest.
Martin

 

[Fred/Belgium]

Randy

-Always wire (its the best safety like when wearing a condome...)
-anti seize everywhere (once I was told, dont use cupper on aluminium but I did not follow)
-Direction to unsrew: one golden rule: always towards the front to unsrew

Hope this helps


Fred

 

[Dalton Veitch]

Jac Mac is spot on. I was wondering if someone would get to this. The primarily forward motion of the wheels provides an epicyclic type of self-tightening. I've seen knock-offs which self tightened until you needed a four foot length of pipe on the spinner undoing tool to get them loose. In this case wire ties were added to the spinners to prevent them rotating any further to overtighten.

I had years of experience with British sportscars with knock-off wire wheels (and a copper hammer) and the wheels were always self-tightening. If they didn't, there was damage or some problem that should have been rectified. GT40's put down a lot more torque and may present different characteristics. And nothing wrong with a good safety approach to avoid any disasters. But I'm sure knock-offs are designed to be self tightening.

Dalton

 

[Julian West]

What would cause drive pegs to work loose??

 

[Mike Trusty]

Saw this torque wrench setup being used at the LeMans Classic last year. It was being used on the cars that have what I would call the "small" knock-offs. I don't think a hammer would work well on these "small" knock-offs.

 

[Dan W]

Besides the wire, I may try a tube of Torque Seal. It is a thick liquid "paint" that is sold in small tubes and you paint a line of it between two surfaces. If it cracks the two parts have started to "shear" or loosen . We use it in aviation, would be intresting to see if it works well on spinners. Stainless wire can strech a bit before failing, maybe this product could warn you even sooner. Here is a website that sells it
F-900 Torque Seal, Inspection Seal Lacquer: Aircraft parts and Pilot Supplies. Since 1969. Call the Chief Geek (866-SKY-GEEK) 100% Satisfaction Guaranteed.

Dan

 

[Scott Calabro]

Not to be gruff but....

John Owen...How does a loose nut stretch .032 or .041 wire? Was a wrench or socket put on it to loosen it while it was wired?

Safety wire gets tighter if a nut/bolt tends to loosen, if its wired right!!!!!

Light wire? ALWAYS fill at least 50% of the hole with wire. The larger diameter wire the better.

Dan... If you wire the spinner correctly you really don't need witness marks. Although it looks trick!

In short..

A little grease

Proper torque

A CORRECT safety (preferably inside a sheath, heat shrink works great)

Done!

 

[Steve C]

I've been doing what Scott recommends above to the Cobra for 8 yrs and now 25,000 miles without a problem...Did have pins in the pin drives on the rears that loosened when car new and traced to 1/2" wheel spacer...removed the spacers,cut down the studs appropriately, turned down a little of the wheel hub to clear the Willwood caliper and no problem for 20,000 miles...Steve C

 

[Howard Jones]

My reason to safety wire is I will know that if the wire has come off it has been broken. I wire in the direction of preventing the nut/wing from coming loose just like all other nuts that get wired. I do it tightly and in earnest. Once done the wing nut would have to turn and break the wire to loosen.

This is a great visual aid. I also always put my foot on each wing-nut and stand on them all the way around before I get into the car when at the track. Good habit.

Anti seize is a must do but don't just slab it on. If you do the rotation will throw it all over everything in range. That stuff is really a mess and you don't want it all over the wheels and bodywork. Start with a PERFECTLY clean nut and threads on the hub and apply a light film of antiseize to the hub threads. Work the nut on and off a few time to spread the antiseize onto the nut threads. I clean up the threads with carb cleaner or alcohol. If you forget the antisieze take it apart right away and apply it, then put it back together. Really..... use antisieze. I saw a cobra with a dry stuck wing nut. Ruined the wingnut and hub getting it off with a huge hammer and a torch. Theres really no pretty way to do that. Use antisieze.

I also have a solid hunk of aluminum about two feet long and about 2 inches square. I set one end onto the wing of the nut to be tightened and hit the other end of the aluminum bar. I have wrapped the bar with tape to keep it from scratching the wheel arch paint. This works very well.

Now the question is how hard to hit it. Well if you can get a good square strike, thus the solid bar, with a 4 or 5 pound hammer then you will need to hit it a couple of times pretty good. Don't go all caveman, just hit it good until it quits turning. Start from a no slack, hand tight nut with the wheel and tire off the ground. One more time for luck and its on.

You will gain confidence in this after a while... and it will be OK. Trust me.

Oh, and don't buy the cheap cast spinners. They won't last and they will break. The good ones are forged and don't bend... ever... if you are doing it right.

Mine came from P S Engineering. Good stuff.

 

[John Lowe]

Found this on the Cobra Forum (thanks Dean), actual torque numbers

"Center lock nuts/ spinners should be torqued to 400 ft./lbs.
This is common knowledge in the pits. Using a gun we have to hook it to a big nitrogen bottle to get the suckers loose. At 400 lbs. they still need to be checked after every run as they may have loosened 3 degrees or so. Also, remember the temp of the assembly matters.
I use a torque wrench(48" long 3/4" drive)."

John

RCR40 soon(ish)epper:

 

[Russ Noble]

To the guys who have stated that it doesn't matter which way the threads are aligned, let me relate this thoughtless instance....

Years ago when I owned a vehicle repair business we had to obtain warrants/certificates of fitness for customers vehicles every six months. One of the testes the vehicles had to pass was on a rolling road checking brake efficiency. Sometimes when you have tried everything and still cannot meet the standard, swapping the drums from side to side will achieve the desired result. This was done with cars on a fairly regular basis and worked well.

We did it to a truck once that we couldn't get the rears even on, pulled the duals and drums off as an assembly and swapped them over. Because we didn't undo the wheels we never thought about the direction of the wheel nuts. The brakes were fine but 50 miles down the road the rear wheels fell off!!!

Not an episode that I am proud of, but it does show what can happen when you stop thinking.

But remember for normal wheel nuts LH thread on the LH side. For centre locks it is the opposite. LH thread on the RH side.

Cheers,

Russ

 

[Randy V]

Thanks Fellas... Here's another tid-bit that I found on a site that talks about the Knock-offs on early Corvettes;

 

[Jac Mac]

????????? Put your thinking caps on guys. Randy the corvette drawing does not make a lot of sense when you think about it, either the knock offs have been designed as easy to tighten or easy to remove , or is it a safety concern to prevent the knock off from catching anything from rotation. Read the text in the article then note the reference to GT40 and then refer to the GT40 pic at the Le Mans Classic with the large torque wrench placed at the RF wheel in such a manner that would indicate a RH Thread on the RHS.

Jac Mac

 

[Randy V]

Here's the link to the PDF file that had the image I placed above;
www.licorvette.com/pdfcatalogfiles/KOwheel.PDF

I'm not disputing anything said here by anyone. I'm just trying to gather a repository of information about this design of wheel for the GT40s community (and m'self of course)

So - what the Corvette article said seems to reinforce that which Russ, Dean and some others have said..
Jac - I agree with you also that it seems odd that the Left side of the car would have Right-Hand threads and the Right Side would have Left-Hand threads..

Note that the Corvette knock-off has a speciel set of pins to assist in locking the spinner to the hub.

Thanks John for the Torque Spec (400 Lb Ft)..

Still waiting on the word from our (so far) Silent Manufacturers...

 

[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....

Jac Mac explained it simply in an email to me :- "Sometimes after dragging the Horse to water the only way to make the bastard drink is to hold its head under water & stick a vacuum pump up its arse!!!" Eloquence always wins the day! It was his gentle way of pointing out that I was wrong!


Anyway why didn't "White Rice" give us the benefit of his knowledge on this relatively important matter boomsmile:lol:

Cheers,

 

[Mike Drew]

Jac Mac is wrong; the standard for knock-off wheels is that you put them "Back On", meaning that they rotate towards the rear of the car to tighten them. Left-side wheels are normal, right-side wheels are 'backwards', i.e. LH thread. I have examined and photographed a number of genuine GT40s and they are all set up that way, as are every production car I've ever seen with knock-off wheels--Corvette, Jaguar, Triumph, etc. and so forth. A friend owns the 2000 Trans Am championship winning car, and it is also set up in accordance with this standard. I can't explain why it's preferable, but the auto industry seems to have standardized this pretty well (perhaps excepting vintage Lotus?)

Here's a photo of the right front wheel on my Cobra:

Note the clip which goes through the center of the hub; this has the dual function of retaining the plug in the (hollow) hub center, and also serving as a backup to prevent the knock-off spinner from departing the car should it loosen.

Mondo safety wire is used, and 'pulls' the knockoff in the tightening direction. Oh, and I liberally coat the face of the spinner and the threads with aluminum anti-seize. I, too, have seen somebody trying (and failing) to remove his wheel; I almost had to resort to extreme measures when I failed to lubricate mine adequately and galling locked the spinner to the wheel. I typically put too much on, tighten the wheel appropriately, then wipe off the excess.

I was also at Le Mans Classic with Mike Trusty, and I saw a different rig for torquing the knock-offs on another GT40 that used Halibrands with the larger spinner. It was a brilliant tool; the tube fit into the center of the hub, which effectively located the tool; the metal flange fit over the spinner, and the end of it was set up to accept a 3/4 inch mongo torque wrench:

Once upon a time I saw another fantastic tool for this job. I believe it was owned by the late Mac Archer, who was driving the famous (on the west coast) #22 red 427 Cobra at the Monterey Historic Races. Picture a two-foot-long steel bar with big weights on each end, looking like a big letter "I". It had an output in the center with a big socket to engage the spinner, and somehow a bearing was involved as well. The "I" could rotate freely about 170 degrees before the "I" and the socket locked up together. It relied on inertia to tighten or loosen the spinner. In practice it the spinner would be tightened as much as possible, then the tool would be put over the spinner, rotated as far as possible in the loosen direction, and then quickly spun in the tighten direction. It would spin until the two parts locked together, and then WHACK the rotational inertia would be transmitted to the spinner.

But truthfully, most people (including me) rely on the BFH. Mine is a Genuine English Lead knock-off hammer. One of these days I'm going to make myself a tool as pictured above.

Actually, what would be good to know is the inside diameter of the hub, to accept the tool. Ideally the Cobra and GT40 hubs would have the same internal dimensions, but what is the likelihood of that?

 

[Russ Noble]

Jac Mac is wrong;

Mike,

In the absence of any tech/physics to support that assertion. I will put my money on Jac Mac and Lotus.

Remember wire wheel knockons are different so quoting Jag, Triumph etc indicates you don't appreciate the basic physics of the discussion.

Cheers

 

[Mike Drew]

Further to my above comments, I did a little web research and discovered that Colin Chapman was contrary to the rest of the auto industry, and indeed Lotus knock-offs are set up 'backwards' from everybody else; the book that Jac Mac references is probably a well-known (to Lotus people) Hugh Haskell book called "Colin Chapman - Lotus Engineering".

Here's what Vintage Wheels (maker of Cobra and GT40 wheels) has to say on the matter:
================
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.
================

FWIW....