First Yamaha

Recently bought an 85 700N, first Yamaha I have owned. Runs and drives really nice. I don't want to get into the debate on pods, this one has pods and it starts and runs and I'm happy with that. I would at some point like to get original air box but from talking with Hogfiddles it seems I must nearly pull the engine to install one as the airbox goes in first. So for now I'm going to run pods. My question is about the "plumbing" that would normally go from engine and carbs to airbox. There is a large pipe, 1/2'', on left side of motor that I think is a breather pipe. Should that have some kind of filter on it? There are smaller pipes coming off the carbs that I think also must go to the airbox in some fashion. Carbs 1 and 4 have 2 pipes, and carbs 2 and 3 have one. I would just like to know what to do with these pipes for now, until someday I can do a complete air box.
Thanks everyone - I sure enjoy browsing the forum! JB

 

Your carburettor pipes will be overflow pipes, they don't go to the airbox. I would put a filter on the breather pipe which would normally fit onto the factory airbox.

 

Very good. I thank you for the info. JB

 

If you don’t, you’re gonna get an awful dirty oily left leg and foot

 

Idealy that breather should go up and into one of your pods, what comes out (and in) depend largely on the state of health of your engine? The carb overflows also need to go upwards, all tied together, my vmax ones are tied to the airbox.

 

+12

 

Actually, good point about those "overflow" pipes - are they overflow or breather pipes? Certainly the vmax ones are breathers - the carbs flood directly into the engine (potential disaster), hence they go up. On the 900 if fuel comes out of them rather than up the jet then they would be overflow I guess? I will have a look.

 

I think they are overflow pipes on the XJ. l don't have any going to the airbox on my 900f unlike the heavier pipe to the airbox for crankcase gasses.

 

Well it's not that simple - I said I would check - there are four overflows - connected to the little diecast elbows just above the float gasket face on each carb. These should go down
In between each pair there is a connection further up the carb body, to the space above the fuel in the float chamber which has a tee and vent pipe - this is a vent, and together with its opposite brother should go up. The fuel feed is pretty self explanatory. Hopefully this helps?

 

You are right Minimutly just checked my carburettors.

 

Thanks everyone for the replies. It makes some sense now. The four lower tubes go down and the two upper tubes go up. I wish someone would have left it stock but it is what it is. Its 10 degrees here this morning so with a little heat in garage I can tinker on stuff. I just got new title, registration and plates in the mail. The treasurers office is closed due to Covid so I got on the website and downloaded a form to fill out and emailed form and copies of title and bill of sale. Then they replied that I needed to download another form, and take original title and bill of sale to a dropbox in front of treasurers office. Along with a check for $73. I was a little worried about that but it all came thru.