1978 cb550 bigger main jets needed screw fit not push fit

[stuartni]

I know people will say search etc but I cant find main jets for my carbs am I rite in says there pd carbs which take a screw fit main jets and the other type take push fit which I bought by mistake there 115 size

[mickwinf]

Is yours a K3 ? They can be difficult to find in the UK, but can be obtained from Sirius in Canada http://www.siriusconinc.com/product-motorcycle_parts-39.htm . I find them good to deal with but watch out for customs charges.