knockon removal for minilites

[richardcox_lotus]

I use some sacrificial card to protect my wheels, albeit they are not minilites.

[stugilmour]

The RD tool was designed for use with Minilite-style wheels, according to their site.

To be exact, it says current version of Minilite, which is kind of an interesting question/concern. Sarto mentioned in the development history piece that he kinda lost the design in a fire and passed on the Elan tool to RD. They could have changed things too. I guess you have to try one on Minilite to know?

Man, those clearances are tight!

[pianoderby]

This is the tool currently sold by Kelvedon on an old minilite. This combination seems like it should work fine, but 14” or newer minilites could be different.

[alanr]

That Kelvedon tool is the tool previously made in the past by Lionel here in the UK however I think it will now be difficult to make it work sucessfully on a modern Minilite wheel. It may just work, but personally, with tolerances being so close, I think using it in practise you will scratch the wheel.
The 'Lionel' tool was designed predominately for use with the original steel wheels and I can atest on the steel wheels it works perfectly. I torque mine up to 180lbs/ft.

Note:- 220lbs/ft is way too tight! My Lotus workshop manual says 180-200lbs/ft is the correct figure.


Alan.

[elans3]

Agree with the above. that tool is exactly the same as my Lionel Roberts made one, albeit mine has "Lotus" engraved on the top of the 38mm hex.
Also I torque mine to 180, and I think it's plenty tight enough, never had any problems whatsoever.

[tonyabacus]

Not wishing to teach granny etc, but there are a couple of comments above regarding getting the wheels undone. Remember that the direction of tightening is contra to travel, which in effact means as you drive the wheel is being further tightened. Hence the need to check the torque setting fairly frequently, which will ensure they can be undone without major difficulty.

Also some of the copycat minilites are a little different to the original magnesium variety, mainly to prevent copyright infringements, so the distance between spinner and centre may well be different. Although I have some original magnesium Minilites I cannot get to them easily to take photographs, but perhaps someone else has some they can post photographs of the centre portion to illustrate the distance.
Tony

[Andy8421]

Not wishing to teach granny etc, but there are a couple of comments above regarding getting the wheels undone. Remember that the direction of tightening is contra to travel, which in effact means as you drive the wheel is being further tightened.
Tony

Tony,

Just to confirm your comments, and to make sure that confusion doesn't enter the subject (again), on a Lotus, the spinners on the right hand side of the car (from the drivers seat) are right hand thread, the spinners on the left hand side of the car are left hand thread.

I am not sure how you look at it, but I would have said that the spinners tighten in the direction of travel, not 'contra to travel' as you have suggested.

Andy.

[tonyabacus]

Amdy, perhaps my explanation is a little confusing, but generally knock on wheels have a left hand thread on the right hand side of the car, and a right hand thread on the left hand side, hence my comment about tightening contra to the direction of normal travel.

Part of the reasoning behind this is that whilst driving, the interface between wheel and spinner is self tightening (for a number of reasons), therefore the wheel should not unscrew itself. The wheel spinner should not be overtightened, initially they should be tightened whilst on the jack to ensure that the two surfaces centralise to one another. Then fully tightened once the car is on the ground.

How tight, there are numerous figures bandied about, but it seems 180 ft/lbs is accepted. Usually the wheel will only continue to tighten to its designed limit. One easy way to check is to take a small length of 1/2" masking tape and ink a line across it. Now place the tape along and bridging the gap between wheel and spinner, next to the line on the spinner mark an arrow in the direction you tightened the spinner. Then slit the tape along the joint between wheel and spinner.

Drive the car for a week or so and then check the tape for alignment of the line on both surfaces, there should be little more than a milimetre or so between them, usually showing that the spinner has moved in the direction of the arrow. If there is more than this then it shows the spinner was not tightened enough and may need a slight adjustment (with your hammer !). If there is no movement ask yourself whether it is too tight and may need readjusting (you may also interpret it as being the correct tightness).

If the arrow has moved to the left, then the mating surfaces of the spinner and centre ring on the wheel need further investigation. It has been known in the past for people to try and machine either surface to remove rust, especially if they have been rechromed, so the surfaces no longer mate correctly. This can be verified with some engineers blue between the two surfaces, once the wheel is removed from the car.
Tony

[Andy8421]

Amdy, perhaps my explanation is a little confusing, but generally knock on wheels have a left hand thread on the right hand side of the car, and a right hand thread on the left hand side, hence my comment about tightening contra to the direction of normal travel.

Tony,

One of the pleasures of owning a Lotus is that Colin did things differently. Most knock-ons (Jag, MG etc) use Rudge-Whitworth spinners that have a female cone in the spinner, that mates to a male cone on the wheel. On the Elan, the opposite is true.

Apparently Colin had to demonstrate this effect to his design team, as a number of the team didn't understand it. There are a number of early Lotus documents including 26R setup material produced which show the L/R spinner setup incorrectly.

There is a great animation on Wikipedia that shows how this effect works, and a write-up in the 'Colin Chapman - Lotus Engineering' book by Hugh Haskell that tells the story. Links below:

https://en.wikipedia.org/wiki/Precession_(mechanical)#:~:text=Precession%20is%20the%20process%20of,a%20direction%20opposite%20of%20rotation.

https://lotuselan.net/forums/viewtopic.php?f=60&t=42758

In summary, Rudge-Whitworth spinners should have the left hand thread on the right side of the car, Lotus spinners should have the right hand thread on the right side of the car.

Andy.

Edit (for spelling mistakes and to add:) An old story, but when I did the original research on this subject a few years ago, the Cobra Club site had pages of posts explaining how to attach locking wire to your knock on spinner, along with pages arguing about which way round the spinners should tighten. A bit of digging uncovered that the Cobra has two types of wheel fitted - a spoked wheel with Rudge spinners and a Halibrand wheel with Lotus style spinners. These need to be done up different ways, and given the focus on locking wire, I can only assume many owners hadn't figured this out and that the wheels kept falling off. To our credit, discussions on lotuselan.net were linked to on the Cobra site as examples of how to do it right.

...and just for what its worth, when I still raced, I found the spinners were tighter after a race than before - so clearly the effect is very real.