Recently bought a 2014 290, and ive had bother with the carburation since getting it.
Turns out I have an air leak on the manifold.
Ive swapped the manifold itself, as well as the gaskets, and it still leaks.

The problem is, when tightening the four bolts, it pushes the rubber gasket out over the top, so I can barely get them finger tight.

Tonight I made a new gasket from gasket cork, and that allowed me to nip it up enough. I will test for leaks tomorrow.

Just wondered if anyone has had the same problem and how they overcame it?

Yes had the same problem on a 2010 ST 250, never did get it properly fixed , bought a new 2013 cabestany expecting a good bike, wrong, same manifold leak, which on those was caused by the nipple where the fuel pump drive connects to.

I was going to fit a 2014 manifold as they are sealed over the nipple but sounds like they are no better. A good fuel proof sealant may be only answer.

So what is up?

Hi guys, I am having the same issue and it’s driving me bonkers. 
 

2012 290cc

if I spray brake cleaner on the inlet the engine dies. I’ve put new inlet gaskets on and new inlet screws and it’s better but still doing it. 
 

anyone got a fix for this? I’m debating splitting the engine and changing the Centre gasket. 
 

would a fuel resistant sealant work better on the inlet rather than gaskets? 

No idea if this is the issue you've got, but sharing something that I experienced...

I've got a 2011 and have had the carb off a couple of times but never touched the actual manifold rubber.

I found I had an air leak around where the carb inserted into the manifold rubber. I re-assembled using silicone grease all around the rubber/carb joint and this fixed it.

 

thanks for the reply Vinne, I'll inspect the connection around the carb. I'd like to avoid using silicone sealant if i can because i dont want to risk the engine sucking silicone in.

I've decided to do a leak down test on the engine first to see if the crank seal or centre casing gasket is leaking and then i will move onward from there.