there has been some question as to what boot to use when installing the 39mm FCR from a YFZ,not knowing my self i opted for what i know .
i took the carb to a local auto parts store and picked up a
short hose ,it was to small it fit right on so i used a hone to remove enough rubber so that it would slip on with very little effort. that done i found that there was a small gap between the carb and the head on the inside of the boot that should be filled .
another trip to the store i found that a plastic electrical conduit was the right size to fit into the hose,cut at a slight angle
to more or less level the carb and give a more clean shot through
the Carb 2 Head Boot (C2HB) . some slight sanding to the inside of the ring gave a better fit tho it may not be absolutely necessary.





this C2HB also moves the carb back just enough so that the carb does not hit the upper cross member