If it were possible to strip the spindle out of its bushings, some nickel based grease would do the job of lubrication.
I presume these units are not designed to come apart ?
No they are not BUT..
On my 2010 twincam the flap started to stick at about 20k. Despite trying various cleaning solutions/ lubes it was completely stuck at 24k so I took it off and put a stainless tube in it's place.
The flap then sat on the bench in a tub full of diesel, played with on occasion for a couple of months with no movement, until I knocked it over once too often!
I was going to bin it but having cleaned all the diesel off I decided to grind off the top of the boss on the inner side where it's been rolled over to see what the bearing was like.
What I found was, I think, a wire reinforced carbon bush.
I started to dig this carbon out and after about 6mm the flap suddenly snapped shut and could be opened easily by hand. I was reluctant to dig in any further because it now worked but decided to make a phosphor bronze bush reamed ?mm h7 to support the end of the shaft where I had taken the material away. This was made as an interference fit top hat shape and tapped 6mm in the end so that I could draw it out if necessary, as I had no idea about the shaft material/expansion rates and didn't know whether it would jam with the heat.
I then made an ally cover to go over the bush, held on by 2 grub screws locked down on to 2 flats I made on the flap valve boss. This keeps the weather/muck out.
The bike is now on 68k and the flap is still free and working like a good un.
Apart from the cables around the pulley I have never used any type of lube on it since I did the mod.
So is the carbon I dug out part of a proper bush or just the by product of the exhaust?
I really don't know without digging all the way to the bottom, which I would have done if the bronze bush hadn't worked first time but it did. So I have left it alone.
Regards
Stan
