Vi Runes explained
There's one set of runes for Vi on patch
11.15
that is the clear favorite for LoL players and pros alike. The best Vi Runes on the position 
Jungle are Sorcery as the primary path and
Precision as the secondary path with a pick rate of 64%. Besides runes you should take a look on Vi Build and if you are interested in pro matches take a look at Vi Probuilds. If you want to discuss
Vi then you should visit the champion subreddit.
Primary path on Vi
Sorcery empoweres abilities of Vi and increases the available champion resources. Most of high elo players – and our LoL pros in the the major regions – have agreed that
Phase Rush is the best keystone rune to run on
Vi.
Phase Rush offers more flexibility and options to betake oneself in and out of danger, which can be helpful since that's essentially the main playstyle of Vi. This is usually followed up by taking
Nimbus Cloak,
Celerity and
Waterwalking.
Nimbus Cloak, which grants movement speed upon using a summoner spell, works amazingly well with junglers in particular as they take the shortest cooldown summoner spell,
Celerity boosts all movement speed bonuses to Vi.
Waterwalking grants movement speed in the river, which helps Vi get around the map quicker. The extra damage will also help in those all important dragon and baron fights.
Secondary path on Vi
When it comes to your secondary path, most
Vi players prefer to go with
Precision.
Precision improves attack and sustained damage on Vi troughout the match. On the
Precision path, the best runes for Vi are
Triumph and
Legend: Alacrity.
Triumph restores on Vi a part of missing health and award bonus gold, if a champion is killed.
Legend: Alacrity grants additional attack speed to Vi.