Centre Locks

[conrod]

As some have already said, for BMW's it is LH thread on RH side of the car, and vice versa.

I know a lot of (non BMW) race teams back in the day the ran RH thread on RH side, and LH thread on LH side. There did not seem to be any issue with wheels falling off or self tightening.

The wheel nuts are tightened between 500-700ft.lbs. The interia of a wheel nut, that weighs maybe 120grams, being accelerated or braked will have little effect over such a large tightening torque.

In my opinion it makes no difference which side they go on. There are other more important issues, such as thread condition, the condition of the tapered surfaces,lubrication of threads, tightening torque etc. that are much more likely to cause problems.

[SP-M3E30]

Interesting, Conrod. So it's possible to have LH Tread on the 2 sides of the car. With this setup you don't need 2 torque wrench (1 clockwise and 1 counter clockwise)

[conrod]

I guess it would be possible to have LH threads on both sides (but why not RH threads?) But I don't understand why you need 2 torque wrenches anyway? You just need one that will torque in both directions, and plenty will do that. On mine you push the square drive right through the ratchet mechanism and put the socket on the other side. A friend has one (Facom) where the whole ratchet head is removed by taking out a pin, and you flip it over so it works in the opposite direction.

[fourmotion]

So this wasn't a clear cut answer type of forum question then lol a few friends have been having a similar debate. Did the BMW works teams run left and right thread? If so you have to think there would be good reason?

Cheers,

Warren

[Ironhead]

So this wasn't a clear cut answer type of forum question then lol a few friends have been having a similar debate. Did the BMW works teams run left and right thread? If so you have to think there would be good reason?

Cheers,

Warren

I think the answers here have gotten as definitive as they are going to. Conrod is in possession of actual BMW Motorsport parts, so I think what he told you is as close are you are going to get to the "ultimate" answer.

I would imagine all the teams simply ran the parts as BMW made and supplied them. There were probably only one or two engineers at BMW Motorsport who knew exactly why parts were designed a particularly way, and I am sure even they "shot from the hip" much of the time and went by instinct.

I think sometimes we tend to deify the people at BMW Motorsport, or those who served on the "works" team, a bit too much. I am sure they mostly are/were pretty much just "car guys" like us, albeit the leaders probably had a bit more education and experience. I can see them arguing at BMW....whether braking or accelerating would do more to loosen the center lock nuts....with no real resolution to the discussion other than "well the thing will be torqued so tight it won't matter anyway." Then, the employee with his nose the farthest up the boss' ass would ultimately get the threads on the hubs to go "his way".

I honestly think that is probably pretty much how it went down back in the day.....

[Shaun]

^^^
I think thats how it still is.

On a side note, and keep in mind I have experience with center locks, can one not have a positive retaining mechanism? For race cars it makes sense to not so you can have faster pit stops, but if you were making a street car with center lock wheels could you not design a pin, set screw or something else into the design?

[Ironhead]

^^^
I think thats how it still is.

On a side note, and keep in mind I have experience with center locks, can one not have a positive retaining mechanism? For race cars it makes sense to not so you can have faster pit stops, but if you were making a street car with center lock wheels could you not design a pin, set screw or something else into the design?

Maybe...but the problem is that center locks make absolutely, 100%, no sense on a street car to begin with. Their only advantage is lightning fast wheel changes (which can still be done with conventional lugs....i.e. Nascar). It seems ironic then to have center locks and then design in a retaining system that would remove their only advantage (fast wheel changes) by slowing things down.

I realize most (all?) people here are discussing center locks as a fashion item....or to build a "true" DTM replica.....so maybe in that venue your retaining system idea does make sense.

[SP-M3E30]

I guess it would be possible to have LH threads on both sides (but why not RH threads?) But I don't understand why you need 2 torque wrenches anyway? You just need one that will torque in both directions, and plenty will do that. On mine you push the square drive right through the ratchet mechanism and put the socket on the other side. A friend has one (Facom) where the whole ratchet head is removed by taking out a pin, and you flip it over so it works in the opposite direction.

Can you tell me the brand of your wrench torque and where can I buy it please ?
Mine has just one direction (clockwise)
Thanks

[jimmy p.]

A) anyone who would "want" center locks as a fashion item,,, is the ultimate hard parker.

B) My car is a survivor, all the hub on my car and in the spare package that came with it are split between RH and LH threads. I think you can definitively put that in "solved" category

C) Not one race team ever torqued their center locks . I do have a big torque wrench,,, but I ceased to use it ages ago. I put them on with an impact and check them with a 3', 3/4" drive breaker bar by bouncing on them with my 230 lbs. If they don't move they are tight, I go drive.

I keep mine on my car because,,, well they belong there and its the right thing for the car. I could have easily made replicas for my silver car,,, and I would not if anyone held a gun to my head. Centerlocks are a necessity if you have a vintage pro race car, or someone is paying for your pitstops. Otherwise,,, hard parker.

Airjacks on the other hand... pretty cool.

[conrod]

Can you tell me the brand of your wrench torque and where can I buy it please ?
Mine has just one direction (clockwise)
Thanks

HI Julien,

mine is Wurth brand. My friends one is Facom. Both of them can torque in both directions by either rotating the ratchet head around to the other side (Facom) or pushing the 3/4 drive through the ratchet head to the other side (Wurth) And you can buy a nice 90mm aluminium socket from here

http://www.m3motorsport.co.nz/products/tools-equipment


Agree Jimmy that a big breaker bar will tighten wheels well. But I don't have 230lbs to swing off one! so I use my Wurth torque wrench with the long extension handle (must be 8' long with that bad boy attached!) The other reason is that I never have problems removing wheels, I have seen people using the breaker bar method overtighten wheels, and then struggle to remove them. And I don't use the air tools either, as it tends to f$#k the aluminium wheel nuts after a period of time.

You are right that race teams do not torque the centrelocks during a pitstop. But they would torque the wheels before a race start. And "calibrate" their rattle guns against a known torque, by the amount of air pressure dialled up on the reg, and you tend to count the amount of "clicks on the rattle gun after the nut has seated, usually 2 or 3.

Conrad

[02fanatic]

LOL! I was watching "Wheeler Dealers" last night and saw the repeat of the Lotus Elan episode (it came stock with threaded center hubs)...when Edd was tightening up the left side front spinner he hammered it "toward the front"...so on the left it's Left Hand Thread Tightening. I didn't see the other side, but I'm sure it must be Right Hand Thread. At least Lotus did it that way....and that's a street car, always was.

[kiko]

Can you tell me the brand of your wrench torque and where can I buy it please ?
Mine has just one direction (clockwise)
Thanks

That's odd! Can you post pictures?

[kiko]

Can you tell me the brand of your wrench torque and where can I buy it please ?
Mine has just one direction (clockwise)
Thanks

That's odd! Can you post pictures?

[fourmotion]

A) anyone who would "want" center locks as a fashion item,,, is the ultimate hard parker.

B) My car is a survivor, all the hub on my car and in the spare package that came with it are split between RH and LH threads. I think you can definitively put that in "solved" category

C) Not one race team ever torqued their center locks . I do have a big torque wrench,,, but I ceased to use it ages ago. I put them on with an impact and check them with a 3', 3/4" drive breaker bar by bouncing on them with my 230 lbs. If they don't move they are tight, I go drive.

I keep mine on my car because,,, well they belong there and its the right thing for the car. I could have easily made replicas for my silver car,,, and I would not if anyone held a gun to my head. Centerlocks are a necessity if you have a vintage pro race car, or someone is paying for your pitstops. Otherwise,,, hard parker.

Airjacks on the other hand... pretty cool.

Guilty as charged I guess.........



Just because it's not a race car it doesn't mean it cant be evocative.....

[Brendan]

A) anyone who would "want" center locks as a fashion item,,, is the ultimate hard parker.

"Hard Parker..." Love it. I might have a new user title coming...

Does continuously modifying and working on your car because you can't leave it alone and then not being able to drive it because you keep breaking it count? :smile2: