Hi guys Can someone shed some light on wether the fuel tank has a breather. The reason I ask is whilst finishing off cleaning the bike I opened the petrol cap to clean around that area upon opening it there was a hiss and a pop sound and fuel came out the cap.this may or may not have been caused by me leaving the engine running for quite a while and the heat generated caused the fuel to expand . Your thoughts greatly appreciated. Cheers Stu
I know that on a 08 onwards blade there is defo a breather pipe. Lift the tank and see if it is possibly being pinched.
Stu, There is a breather , if yu over fill the tank you should find the fuel under the bike there are 2 or 3 rubber pipes you should be able to see underneath on the left side. If you are hearing a hiss and a pop the pipe is likely blocked this isn't a good thing. This can cause the pump to fail and or the engine to run rough as it struggles to put fuel from the tank into the engine due to a vacuum. I would suggest before to run the bike for to long that you get the pipe cleared. On my triumph I just passed a long piece of strong but flexy cable down to clear it out Hope this helps.
Cheers Jbully -uk Engine runs fine,i will check the pipes I know where they exit out the bottom of the fairing on the left hand side but I thought they where for what you where saying which was to remove overfilled fuel ,but once the cap is closed this is not used so there must be some other means of venting the tank. Cheers Stu
Stu, they also deal with fuel expansion in hot weather , so they work even with the cap closed. This is why you heard the pop when you opened it, the pipe allows the air in as the fuel is used preventing a vacuum in the tank. If the pipe is blocked the air can't get in and causes a vacuum This is for different bike but shows some of the issues if it's not cleared Motorcycle Message Board - Motorcycle USA
Cheers Jbully-uk No what your saying had no running issues what so ever,like I say had the engine running for a good 15 minutes on idle ,I noticed even the frame rails down the side of the tank even get hot so I know this would help towards expanding the fuel air in the tank.does the tank vent out of the filler cap or down one of the pipes .the only reason ask is the cap has been fitted with a carbon filler cap protector and was wondering if this could be blocking a vent hole. Cheers Stu
Stu, I think It can do both it's meant to vent down the pipe but if it's blocked The fuel can vent round the cap. This means it pisses over the tank and in the case of my triumph leaves a bad stain on the paint work. I have put a protector round my fuel cap as well Honda hrc stick on one , not cased me any issues.
Thanks for your help bully-uk,will check the the pipe to see it's blocked or trapped,can't see it being blocked it ain't done enough miles to be fair. So are you saying the overflow pipe is the same pipe used to vent the tank? Thanks in advance Stu
Hi Guys Well had a bit of time on my hands today so thought I'd have a look and see if I could find anything amiss. So took the tank cover off ,seat off ,unbolt tank and lift rearward so able to view pipes underneath and low and behold off the t piece on the right hand side of the tank there is a 6 inch pipe that connects to nothing and this had been trapped and kinked about an inch from the end, see pic above.rerouted the pipe put everything back together and bobs your uncle no more pressure from the tank when opening the cap. This must have been like this from new .Anyway I'm a happy chappie now. Cheers Stu
