Alternator cover thin lip with the grain

[4pots1969]

Here is a photo of a lid of alternator has thin lip with the black bottom with the grain..
Is this a falsified Alternator Cover? If Yes... What is the interest in knowing that it is recognizable by the grain from the bottom?
Where do really exist with grain in black background?  

[markb]

Someone else jump in if I'm wrong but I think there are (at least) three versions of alternator covers on the sandcasts.
1. Thin lip with smooth background - The distinctions list says up to #342 but I have some notes that say they went to #835.
2. Thin lip with dimpled background - up to #2134 according to the list.
3. Thick lip with dimpled background - #2135 to ??
So I think what you have there is not a fake.
Mark

[4pots1969]

Thanks Mark for these details, there are therefore two different models with the thin lip.

[markb]

This link may help (or confuse) the discussion.
http://cb750sandcastonly.com/smf_forum/index.php?topic=881.0

[Sam]

#410 has no grain in the black area of the alternator cover.

[kp]

Thin lip covers come with no ripple and smooth The early ones are smooth Nevertheless a thin lip is a diamond in the rough so smooth or rippled is still a good find