I just love how low key the antics in this film are. The literally suicidal biker gang-turned-deathless racers don't really seem to have any grandiose plans for world domination, just annoying truck drivers and terrorising their local town centre! Its really less about the scares and more a post-Easy Rider moral tale about the perils of succumbing to peer pressure and the thrills of the road! But the motorbikes are still cool enough to subvert any preaching to the kids about not falling in with the pack!
While they're a bit jarring in comparison, I seem to remember that the film goes truly loopy in its subplots with the duo of satanic psychic Beryl Reid and jaded toyboy butler George Sanders. Doesn't it also involve the biker leader coming face to face with something like his 'spirit animal' - a giant toad?
Though this is also worth watching to see the way that British horror films of the early 70s were falteringly trying to move away from the period gothic Hammer horror approach and trying to directly appeal to contemporary 'youth' audiences. Films like
The Haunted House of Horror,
Tower of Evil,
The Satanic Rites of Dracula (starring Joanna Lumley just prior to her New Avengers/Sapphire & Steel TV fame), and so on, in which groovy kids meet a horrible end! Though
Dracula A.D. 1972 was perhaps the most hilarious and notorious example!
(Its also these slightly tone-deaf with regards to the youth of today, though often fun to watch, films that makes Pete Walker's films like Frightmare and House of Whipcord stand out even more, especially as they literalise the generational conflict angle and develop the youngsters more than just being one-note groovy! In fact
House of Whipcord and
House of Mortal Sin are all about the older repressed generation trying to reduce the younger one into just being licentious kids deserving of punishment!)