Covering on Original Levers

[kp]

I'm putting this post in general discussion hoping to get some responses.
I want to keep my original levers but the factory covering has deteriorated on most and so I have to either replace the lever, use as is or restore the covering. Original levers are definitely different to later levers
My question is -  does anyone know what the original covering was/is made from. Some say plastic, some say they were dipped, but I'm lost on this one and certainly not sure what was used.
I do believe that the original covering yellows over time. I have a few NOS levers and some seem to be clear and others seem to be at the beginning of the yellowing phase. The only thing I can think of that yellows over time is clear enamel paint
Anyone have any thoughts or information on this

[hondasan]

Good question!
I have come across levers which have been bent, causing the covering to crack - it can then be peeled off as if it were a plastic "sheath". Older levers seem to go "milky" internally, caused by (I think) moisture getting down between the coating and lever (corrosion of the lever). I have also had ones that have yellowed with age.
I do wonder if the coating is some kind of plastic applied by dipping, which does not bond particularly well to the lever itself.
Having run out of NOS correct levers (never had very many anyway) I recently resorted to using clear 3:1 heat shrink to sheath some levers for a 400- restoration (new end boots fitted after the heat shrink). Turned out okay - way better than no sheathing - though the end result is thicker than the original plastic was. No idea how these will age due to use and time.

Chris R.

[DW69K0]

My two cents-
The clear coating is very consistent in thickness and length. I soaked a piece in lacquer thinner and it did not disintegrate after one hour, I don't believe they were painted. Brake fluid doesn't seems to effect or degrade the coating.
I am thinking they are covered with a very thin tubing and not dipped or painted.
Clear when new, but yellows and becomes brittle with age.
DW

[Sgt.Pinback]

Never done it myself but I would try it with liquid latex.

Maybe something like this that makes it thicker

https://www.ebay.com/itm/1-Litre-Liquid-Latex-and-100ml-Thickening-Agent-Mould-Making-Dipping-Rubber/164238284448?hash=item263d5d56a0:g:YZUAAOSwEmFapvFF


Or some dozens of layer of clear coat?

[CBman]

Quite interesting this mystery was just not clarified earlier. Dipping lever to any plastic maybe sounds strange, but this special "coat" goes all around rounded lever´  end nicely, so it is closed at the end. So hard to say this could be made by plastic tube.
On the other hand, dipping would make any casting mark ( but there are no signs of it) and this process needs propably more time in production than to heat any stretching  closed one side tube.......
Even dipping, or even tube, I´ m wondering what makes this coat so hard and keeping its shape even the moisture gets inside of it, so just not sticked perfect on the lever.