Breather Pipes ???

[badredwedge]

Got a breather pipe on the 400 hotwire. It runs from the flame trap D/S rocker box to front of throttle pot ( no problem ), but has a tee off to to the front of the base of the plemum chamber which allows free passage of air ?? is this correct ?? should it be like that ?? will this allow unmetered air in ?? I am looking for the cause of a slow return to tick over ?? ( no air leaks that I can find, new steeper motor fitted, base idle set as per RTs instructions ) Any ideas ??

[GreenV8S]

That's correct, but the hose to the trumpet base should be small and quite restrictive. The idea is that the small hose sucks breather gases out under part throttle, and the breather gases are blown out via the bigger hose under full throttle.

[badredwedge]

GreenV8S said:

That's correct, but the hose to the trumpet base should be small and quite restrictive.

Thanks Peter. how small ? its got a 1/2 inch bore at the moment, this must be too big !!

[GreenV8S]

Only a few mil, but you could get away with a bigger one if there was a restrictor at any point.