Infinity focus adjustment

[Tristin]

I recently dissembled my Nikkor 105mm 1.8 and had to take apart the focus ring to clean a helicoid.  This meant putting it back together as closely as it was prior as I could, since it sets the infinity focus.  Today I tested it out.  Aiming at a radio tower probably around 8 miles away on a tripod with magnified liveview, I set the lens at f/1.8 and found that it was focusing in just a bit before the lenses infinity hard stop, hitting the infinity hard stop threw it out of focus somewhat.  I have two questions.

Was this a good testing method? 

Does my result entail any performance degradation I am unaware of?  I am assuming I am losing a bit of close focusing distance, but I am just guessing.

[pluton]

I have used this method with my "Scotch Tape Infinty" lenses, the 135/2 Ais and 84/1.4 Ais.  As I recall, the taped rings were directly under the rubber focusing grip, so easy off, easy on.
 If it's the same on your 105/1.8, remove the tape, adjust infinity, and replace the tape. 
The nice thing about the Scotch tape lenses is that you can go back and re-adjust infinity without taking it to a shop.

[Erik Lund]

,,,, found that it was focusing in just a bit before the lenses infinity hard stop, hitting the infinity hard stop threw it out of focus somewhat.....

How much is a bit on the scale on the lens,,,

ED lenses focus past infinity so does many other lenses,,,

[richardHaw]

i was told that this focusing pas infinity by a bit thing was done on purpose to accommodate glass expansion when the glass is hot under the sun 

you can change that easily by adjusting the numbers and then taping it back 

on series E lenses and many 80's Zoom-Nikkors, it's another story.

[Erik Lund]

i was told that this focusing pas infinity by a bit thing was done on purpose to accommodate glass expansion when the glass is hot under the sun 

Yes it is, for ED glass.

[Akira]

Ais 105/1.8 doesn't use ED glasses and should have the infinity stop right at the infinity...

[simsurace]

Doesn't non-ED glass also expand?

[Erik Lund]

Not to a point where its a problem.