[Alice Breil]

My 1997 750 has the same black triangular housings. The 'inside' one of the two housings has two hoses entering it. One of the hoses goes to the right (front cylinder) carb; like Pat says, there is a metal elbow fitting on the outside of this carb, just under the air filter box, and the hose slips onto that fitting. The other hose disappears up between the two carbs somewhere, where it must fit to the other carb.

This 'inside' housing has two extra holes in it, right near where the two hoses enter it.

The 'outside' of the two housings has a hose coming out of it at the front top but I can't see where it goes; my Haynes manual refers to that hose as 'the bottom breather hose' and the other two hoses as 'the top breather hoses'.

The two hoses that go to the carbs: about half-way along each hose there is a small black plastic thing fitted in-line; they are about the size of an in-line fuel filter but I don't know what they do here; some kind of one-way valve?

 

[Alice Breil]

Instrument lights on mine; top row from left: neutral, low fuel, indicators, oil pressure. Bottom row from left: lights on, high beam, stand down, charging.

 

[Alice Breil]

I've had it for 10-plus years, but it was unregistered for a few years until just over a year ago.

 

[Alice Breil]

No problem. I am not much help if you need technical/mechanical advice (Pat's the man there) but I will help if I can. The 400 should be a nice bike; lighter again than the 750, less power but just ride it accordingly.