Royal Enfield Thunderbird 350 On Rent In Delhi The smaller engine of the Thunderbird 500, the Thunderbird 350 will hold its own against any other motorbike and then pull some more. The Thunderbird 350 shares its powerplant with the Thunderbird 500 cc twinspark. This is a motorbike that does not need to shout to be heard. Born of a rich heritage and bred with royal elegance, this Thunderbird 350cc thumper has all the qualities of a typical Royal Enfield.