Some people may already know how to gain Bug Frags quickly in this game, here is a way to make Bug Frags appear quickly for starters. In order to gain many Bug Frags, you must gain the Battler Card in Class 1-2 Comp with only 2000 Zennys from the Red Punk Navi. Gain "Rare" viruses in order to win against the Virus Machines in different comps.

Here are the locations of the Virus Machines. (Note: You must defeat through the V1 first.)
1.) Virus Machine V1 - RoboDog Comp
2.) Virus Machine V2 - Water Machine Comp
3.) Virus Machine V3 - Punishment Chair Comp
4.) Virus Machine V4 - Gas Tank Comp
5.) Virus
Virus Machines V4 and V5 are not included in this process, but if you want to gain the Super Vulcan S chip, feel free to not hesitate.

Defeat through V1 and V2 to battle V3. Defeat V3 once in order to gain the main prize. Then, challenge him again and again. He gives you either 1500 Zennys or 6 Bug Frags. This process needs luck. I was able to gain about 300 Bug Frags or higher using this, and it is really useful. I hope some of you thinks this is helpful.