Lotus Elan and Lotus Elan Plus 2 Forums

Having had the engine and 5 Speed gearbox rebuilt l thought it best to complete the jobwith a new clutch plate.
The existing clutch cover is Borg & Bech with an AP clutch plate which does seem to have plenty of wear left.
My enquiries about the appropriate clutch plate have revealed many comments about having to shave 5mm off the central spine shaft.
Unfortunately there dont seem to be any references about whether such reduction is applicable to a particular brand of clutch and there are mixed references as to whether the reduction should be off the Flywheel or the Pressure plate side. The original Lotus advisory l have seen seems to suggest a reduction to the flywheel side which doesnt seem right to me.
I have not seen any reference to how long the central spline shaft should be to ensure no dragging of the plate. I have a new Helix plate but on speaking to a Helix agent they advise having no knowledge of any need for such a modification. Maybe this would be the case if l bought a New Helix Pressure plate as well but l thought plates were interchangeable by brand. Having said that references to other Lotus Parts speciaists has also drawn a blank.
This seems to have been a subject raised on the forum in different guises over the years but l find there is little reference to specfic Plate Part Numbers and the required specification required etc.
Any specifics on the way to proceed would be appreciated.

Remember that the spigot bearing is held in a special retainer in the centre of the flywheel because of the shorter input shaft of the 5 speed box This moves the bearing closer to the clutch plate so maybe this is where you need extra clearance. [ This is from a distant and failing memory ]

Have a quick peek at this...

lotus-gearbox-f37/speed-clutch-t29900.html?hilit=clutch%20plate

John

P.S
My lathe wouldn't fit the clutch plate so just cut a little piece of the right diameter bar,locked in the vice and balanced the plate on it....an angle grinder to the offending part grinds away while spinning the plate to give a good finish..

John

I bought a complete new pressure and driven plate from Sue Miller and had no problems.

Maybe the mod is not required these days?

Thanks everyone for the responses and cross references.
I am still feeling that there is an absence of numeric specification of what sizes l should be targeting . The Lotus advisory does not refer to the dimensions to be achieved on the Central Spline of the Clutch plate or whether the original problem is specific to one brand of Clutch. It seems the only way to check if the clearance is ok is by fitting the plate and installing the engine for testing and maybe having to do it all again.
It is unclear whether the problem is still around given that some folk are saying they recently bought a new plate and fitted it without any issues.
I note that the length of the central spline on the new Helix Plate l have is the same as the shaved spline of the AP plate l removed. I also note that the AP plate was shaved on the pressure plate side contrary to the Lotus Advisory.
Having said that the Helix plate has a thicker cross section profile and it doesnt look as though there is 5mm on the flywheel side to remove.
Does anyone know if there any specifications available anywhere. ??

Like so...




John