Wont start up again

[usmc_scott]

My xs has been very off beat lately. It used to start right up when cold or warm. BUT lately its been downright impossible to get it running. First experienced this when I took it for a ten minute ride. Parked it went out to take another quick trip and it refused to run unless I held the throttle open a bit. It wouldn't go over 3000 rpm and if I let off the throttle it would die. Finally after about 4 minutes of messing with it, it ran just fine. Then I put it in to a storage facility because I'm moving. Ran just fine, came back the next day to go for a ride and it refused to even sputter. Tried to start it for so long that my battery died then I jumped it with my truck battery. It turned over with more gusto than ever before but still wouldn't fire up. All I got was a huge ear poping back fire. Finally gave up and here I am. Yes I have fuel filters. Lines are not kinked and I searched the forum but couldn't find anything. Please help.

Its a 1981 xs11special

[DGXSER]

I would start by checking battery. Could be very weak and not giving a good spark.

[natemoen]

When was the last time the carbs were cleaned? Has it sat for any period of time without being used?

[jwhughes3]

I think Nate is on the right track...

If it was running and wouldn't rev above 3000, then either fuel or air were limited. it is more likely that a fuel restriction exists - a clogged hole in a jet or two from sitting (were you deployed?) or gummy gas.

you might try running with a test bottle of gas hooked to the lines and put some of that Start your Engines stuff in the gas to help dissolve varnish.


Don't forget don's advice on the battery - charging fully first may help in eliminating spark as an issue.


John

[soccer4m]

try this

If the bike is turning over fast with a car hookkup it shouldnt be the battery,,,,
check your fuses, maybe wiggle to get a good contact and check current across each one.
Also,,,check kill switch if accidently turned on...
Also check fuel petcock valve, turn to prime,,also check gas level-is the tank full????
Also check to see if gas is filling the fuel filters to show there is flow to them, and let us know if any of those checks works,,,,,,,,,,,,,Mike in Sun DIego

[Ken Talbot]

Mu guess would be dirty carbs, in particular the low-speed circuits.

[planedick]

Next time

Had that problem once. Wouldn't start cold and when setting hot for a few minutes. Using a peice of fuel hose, I put a small amount of fuel into the vac ports on cyl 1 & 4 and it started right up. Idle was set a little too lean. If that don't work, maybe it's too rich.

[usmc_scott]

thanks for the input everyone. ill try giving the battery a good charge up first then go from there.