Scratchy speedometer fix?

I just got around to pulling the front tire back off to replace the speedometer drive unit in the wheel "hub". (I had the front tire off to replace the front tire, obviously, and had the fork seals done but didn't install the new drive unit I had bought for some derp-y reason).

So basically, "new" drive unit, and the speedometer cable was brand new when the previous unit blew on me and has a total of maybe 50 miles of revolving in the sheathing. I am 90% positive that the scratchy sound is coming from the speedometer itself. Is there a fix to this or do I have to replace the whole gauge?

Also, what should I lube the cable with?

 

Speedometer and tachometer drive cables can normally be removed completely from their outer sheath, and then both the cable and the inner sheath can be cleaned well with a solvent such as aerosol brake or carb cleaner. The cable should then be lubed generously with fresh motor oil (we like the Castrol brand 5W40 synthetic motor oil), drive chain lube, or penetrating cable lube, and then as it is re-inserted into the outer sheathing, spun around by hand to distribute the lubricant, and then the cable should be hung vertically for a few moments to allow excess lube to drip out. A small smear of moly grease at the bottom end finishes your cable lubrication procedure.

 

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