1982 yamaha xs 400 modifications

[JARichmond]

Hey guys. I'm new to the motorbike scene and picked up an inexpensive XS 400 Heritage. I'm eventually hoping to turn it into a bobber but want to start small. First I want to toss on a new air filter and free up a bit of space under the seat. I'm wondering what kind of work I have to put in to the carbs. Will I have to adjust the air-fuel ratio? Is there anything else I have to do to accomodate that modification?

 

[PeterTrocewicz]

Chances are you won't have to do anything with the jetting yet, until/if you change the exhaust. Unless you go to a very open intake setup. The pod filters that people use when doing this, which is a very popular modification, generally work pretty well with the stock jetting. You may have to move things around under the seat, but not very likely, the new filters should just go straight on. Just use fresh spark plugs, and pull them once in a while to look at them as you make you modifications: the firing end should be a tan colour. If they start turing grey or white, you are running lean due to increased airflow through the engine, and you need to richen up the jetting a bit.