Maxim 650 issues. Not running smooth / Stalling

Heres the story

Was riding my bike to the store and as im coming down this street, i felt as if the bike was choking and struggling to move. I would turn the throttle and nothing would happen. Bike would kick on/off with this choking problem so i turned onto a side street (I thought maybe my bag was hanging off because it felt like it was dragging) and i was going to park it in neutral and see whats up. I turn down the street and the RPM needle just dropped down and died out.

Took forever to get it started again, i turned around and headed back home. Stalled a few more times and the last time i had to screw with the choke to really get it going. (It was properly warmed up, i always warm it up properly)

So i have it home now and my brother noticed an air tube was slipping off (Doesnt really matter i dont know what its called but we fixed it and the bike is still having the same problems)

I took it around my block. Started up fine (Despite the fact that i always need to give it a little bit of gas to start, probably a clogged fuel line in the carburetor but thats another issue )

So i started, warmed it up, took it around the block. Started dying out and it just chokes, then kicks back and then i got it home and when i tried to idle it, it just died out.

What im thinking is it's an air issue. I couldnt start it up but when i gave it choke it started (While its already warmed up) so if it starts RIGHT up and has no problem with the choke, but as soon as i turn off the choke the RPM needle drops and the bike dies out, im assuming air problem...

Any ideas guys?

 

Sounds EXACTLY like what happened to me today!

Check out my thread, the answers may help you as well.

http://xjbikes.com/Forums/viewtopic/t=33315.html

 

It would be a big help to those of us who help try and sort-out problems for the Membership, ... to be able to look at your Post and see the Signature Section filled-out with some Basic Information.

Year <> Model <> MILES <> Stock/Modified

That said.
AIR is the least likely issue.
There's NO Choke on the XJ-Bike. The "Choke" is an Enrichment Device.

If the Bike will run with some Enrichment, ... the problem is likely to be Fuel Delivery.
At least, ... FUEL Delivery related.

Test the Petc0ck.
Open a Fuel Bowl Drain and see if its getting Fuel.

Then, ... If you don't know when the last time the Carbs were thoroughly Cleaned, ... you're due.

A good friend and one of Yamaha's Best Technicians, Nationwide, once instructed me on evaluating running issues relevant to XJ-Series Bikes.

"If a XJ Series Bike is running, but not well, ... 95-percent of the time, it's the carbs, Rick. It's the Carbs."

 

Maxim 650, 1982 with 14k miles. previous owner upgraded and the bike was sitting out in the rain but ran fine.

My brother helped me out, we switched the petcock to prime and it ran perfect. When we put it into the "On" position it wouldnt get the gas and it would die out.

So i need to replace the petcock and the inline fuel filter.

Are they universal parts or do i need to look specifically for an XJ650 petcock?

 

water in the gas? About two weeks ago I filled up and my bike died. I got it started it got me to work and as I pulled in to a parking space it died. It refused to start. Turned out I had bought a tank of water with some gas in it. I ended up dumping all 2.5 gallons of the so called fuel and getting fresh gas. I dumped in about 1/4 a bottle of dry gas and let the bike sit over night the next day she fired up ran rough until the rest of the water was worked out of the fuel system. I added more dry gas and filled up at a different station.

 

That or you may not be getting a good vacuum pull on the petcock. Before you replace or rebuild the petcock, check for a missing or cracked hose from the vacuum port on the petcock to the vacuum port on top of one of the carbs. To check this, you can put a clear hose on the vacuum nipple of the petcock and with the fuel hose disconnected and routed into a bowl, check the flow of gas out of the petcock by sucking on the vacuum hose.

 

Sucking on the Hose is part of Testing the Petc0ck.

Fuel should flow and stop as vacuum is applied to the line.

IF, you taste Gas, ... the Vacuum Membrane is compromised and the Petc0ck will not operate properly.

IF, the Hose is NOT Vacuum Hose it will Kink or Collapse upon itself shutting-off Gas Supply.

 

Man oh man. The bike has 14K on it, and I've got a shiny new $5 that says the valves have never been touched.

Please read this: http://xjbikes.com/Forums/viewtopic/t=33042.html

And this: http://xjbikes.com/Forums/viewtopic/t=32118.html

And get after the valves before you burn one. Honest, don't put it off or dismiss it as unnecessary; that's what everyone before you did. This might help: http://xjbikes.com/Forums/viewtopic/t=14827.html