Carburettor Size


Well-Known Member
Hi, SU carbs are size designated as one inch plus the number of eighths of an inch. So HS OR HIF 6 is 6 eighths or three quarters.



Active Member
Thank you so much guys for the info
Sorry I have another question I wish to change my air filter for the pan ones you can get now,
Just to make it more easy to get to the carb, the old air filter has a breather pipe
Some of the pan air filters I have seen for sale dont have the connection for the pipe
my question is do I need a pan type with the connection for the air pipe or can you just delete it ?
Cheers Guys