Here's Arachnor and Diabolico
Once you see Jinxer and a weakened Olympius in the cave, that's when it's the start of new footage outside of the Skull Cavern.
This shot of Arachnor's Spider Web is when it goes back to Sentai footage.
It then cuts to the Aquabase scenes and then back to Carter training with the Trans-Armor Cycle and then it cuts to new footage of Arachnor.
Here's the Red Ranger on the Trans-Armor Cycle  
Here's a shot of the Red Ranger with the Trans-Armor Cycle's Armor
Here's another new shot of Arachnor
Here's some more shots of the Red Ranger with the Trans-Armor Cycle Armor  
Sentai info comes from GoGoV Episode 18