250-500cc Gas intermittently flows out overflow hose

I can not make the CARB on this 08 WR250 quit spurting fuel out the overflow hose ... Its not a constant drip, but if the gas is left on, the bike will just spurt gas out the over flow and then maybe quit and then spurt again ...

I've been in the CARB about 5 times now bending that tab down on the floats ... I'm not sure where it should be set but can't keep bending it downward I'd guess ..

Is there another possible solution for stopping the gas spurts other than bending the tab down on the floats?

There is a oring around the brass piece that the needle sets in that looks a little dry ...I'll probably start there as the needle looks OK and clean...

Thanks

It's best to get an OEM "O" ring because they are slightly different in diameter than the ones in the assortment boxes. Replacing the "O" ring solved what seemed like a jetting issue on one of my YZ125s, it never dripped but would sometimes run rich on the top end like the main jet was too big... probably a high float level from an old leaking "O" ring.

I normally just live with issues here or get some fix and then when I order parts, get the correct part and replace whatever I hacked to keep riding ... Probably the biggest issue here is leaking\wasting gas when riding out the tube ... Cutting the gas off at the tank when stopped is the fix when parked ..

I take a qtip in a cordless drill with some mothers polish on it , then polish the needle seat, and then flip it over and use the dry side to clean it out , this has worked for me before...! its cheap and easy and worth a try.

The problem with this issue is that it can be more than a nuisance. If the fuel is high enough to get into the overflow tube, it's going to jack up all your jetting settings and the bike will/might run rich. It's just like having your floats set wrong, except you also waste gas pissing it out on the ground.

had same with my mikuni cardm there was a slither of rubber from the gasket that was trapped unnder the seat of the needle valve i had to unscrew the nut thingy and cleaned the hell out of it, i found it the 4th time i washed the thing out as it was the only thing that i hadnt checked.
good luck

Are you taking about removing the main jet only OR the piece the main main jet screws into?

EDIT: I guess you are talking about the piece the needle sits in? That's the piece that has the small o-ring on it?

yeh the bit the sits in, the seat im not sure what its called cus im usless, but the rubber bit was stopping the needle sealing, but didnt go through the carb to engine.

I have the same problem I recently had a knock and since then I have had a problem with my fuel tank where if I fill it over 3 quarters the fuel just runs out of the overflow pipe. I have put a small bolt in the end of the pipe but then it leaks out of the fuel cap.

A new tank is not in my budget so any help or suggestions would be great.

Is it coming out the overflow hose on the CARB, or the vent hose on the TANK? This thread is about overflow from the carb (which I don't think your 2009 610 has, so it's probably not the right place for this).

Sorry guys
It is coming out of the vent hose on the TANK

Been having the same trouble with my Mikuni. Please post your findings, I'm curious as to what it might be. I'm just about to swap my carb, I'll let you know what I find.

Had the same problem with a brand-new bike back in the day and had to clean the orifice that the float needle went in to. Flushed some kind of debris out of there and was good to go.

buy an acerbis large gas cap avail on eBay.

I'm having the same problem with my brand new bike it's just spews gas when it feels like it and won't stop.