Do the वैंपायर have fangs when they bite या they just dont have them at all?

They don't have them at all. Stephenie explains about their fangs link.

"My वैंपायर do not have fangs. Their teeth are so sharp and strong that fangs are hardly necessary (they could bite through steel, if so inclined–a human neck is like butter, ha ha). The non-vegetarian वैंपायर don’t leave living victims (unless they are changing someone into a vampire); this isn’t the neat-and-tidy, two-small-holes-in-the-neck kind of vampire attack that आप see in other vampire mythologies."

stephanie meyer's वैंपायर don't have fangs and are nothing like वैंपायर we used to, so everything आप know about them (vampires from पूर्व पुस्तकें and movies), all the myths,it doesn't involve stephanie's vampires.. so they don't have fangs but do have very sharp teeth with venom in it.. that's why edward doesn't french किस bella, because she could easily cut herself..

twilight वैंपायर dont have fangs because their teeth are already sharp enough thats why when they bite someone, it makes a cresent mark, not two little holes

वैंपायर are REALLY different in stephenie Meyers books, we wouldn't expect any वैंपायर to be vegetarians would we, we thought वैंपायर would be all gothic, biting humans, having fangs ect. But in stephenies पुस्तकें everything is different, thay can be vegetarians, they are not all गॉथिक and THEY DONT HAVE FANGS AT ALL!!. xx Also instead of making 2 little holes like a vampire with fangs would, it makes a creasent mark.

Idek

yes but not in Twilight

No, those 'Vampires' don't have fangs.
Coming to think of this, having read some of the पुस्तकें and seen all of the फिल्में due to being a movie/book reviewer for a local paper... I can, as a mythology प्रशंसक as well as a die-hard horror story/movie fan, say I don't even see them as vampires.
Calling these creations वैंपायर is like saying a white dog with black spots is a cow या a panda-bear: They share similarities, yes, but they aren't what आप call them. I prefer to see them as disco-globe mosquitos.

वैंपायर do not exist so the सवाल is invalid.