1982 Yamaha 650 Seca XJ650RJ - idle dies

[alexp]

1. Engine completely rebuilt a few years ago - running fine
2. Full tank
3. New AGM batttery
4. Start engine - runs fine - drive 1 mile and stop for 30 min.
5. Get back on bike. Engine restarts fine.
6. Idle for a minute with petcock on Fuel
7. Suddenly - engine starts to die, as if there is no gas.
8. Crank engine - won't restart
9. Set petcock to Prime and crank again.
10. Eventually engine restarts.
11. Idle with petcock on Prime for a minute.
12. Engine again dies as if there is no fuel.
13. Restart engine with petcock still on Prime.
14. Engine restarts eventually.
15. Move Petcock back to 'Fuel and ride bike a few miles - runs fine.

What's going on ?? Has never happened before.

Thanks.

[brajon]

Check the intake boots if there's any crack.

[ZooTech]

Could be a lot of things but I suspect a failed vacuum diaphragm in your petcock, or the hose that provides it, or sticky floats.

[pchast]

I had to pull my fuel valve and clean the vacuum chamber of dirt.

[totalmotorcycle]

I had the exact same bike and mine did something like that for a month till I figured it out. With mine it was the left rear turn bulb causing a short, the bulb was rusty on the end of it, once I replaced it, all fine. So I'd recommend checking all your bulbs. Yes, odd suggestion, but it worked for me.

Also, check both ends of your battery ground as well.

Mike

[NorthernPete]

Side note on this thread: welcome back zootech! Been what? 12 years? Lol

[ZooTech]

Side note on this thread: welcome back zootech! Been what? 12 years? Lol

Yes, I believe that's about right! Was quite surprised to find my username still worked after all this time...