The World’s Biggest and Most Powerful Diesel Engine

[Chas]

The pre war bikes I rode never had an air filter. They had Amal carbs with funnel shaped air intakes screwed onto them. Must have been a lot of dust on pre war roads.

Yes, I had a Lambretta scooter that I had modified by putting a venturi tube on the carburettor intake that never had a filter to start with. There were other mods I did, head skimmed, straight through exhaust, hole cut in the side panel with a scoop to increase the air flow to the carb just benind which increased the max speed from 57mph to 82mph, which I considered a fair increase but the engine didn't last very long after that.

 

[SafariTecPeter]

"Open" or with a Funnel fed Carbs is fairly common on some juiced up road cars even today.
My best friend has got 2 V8 Ferrari-Engines in his race boat with open funnels feeeding the 4 rabs on each engine (sorry, got no pics).
In some cases, the air filter is a restriction that is unwanted. One has to take the operating conditions into consideration.
IIRC, Air filters became more comon in the early 50-s. My "only" reference to that would have to be old VW`s, Yankee irons & a few more.. Probaly also to do with bigger focus on the effect that dust could cause on the engine (premature) wear.

Still Clive 600K on Your old dads van is a descent milage