Engine won't start after running

[Anonymous]

Hello everyone.

Having problems starting my 1980 GS550L after it has been running. If I let the bike sit for about 30 minutes it starts right up. The spark and compression is good on all cylinders. When trying to start I can observer gas going to the #2 carb but will not fire on the restart. Cleaned and dipped the carbs yesterday. All the carb o-rings have been replaced and manually sync the carbs. When running, enging idles about 1500-1700 RPMs and good at higer RPM's.

Bike runs good but will not restart and any insight to this problem would be greatly appreciated.

[hoyterb]

Float levels may be too high letting a slight amount of fuel to flood the engine.Your choke may be causing a rich condition when starting hot also.

[Dark Jedi]

Have you re-done your fuel lines? I had this problem a while back on an 82 GS1100ez after replacing the old fuel lines with new ones. I had them too long (Wanted more room to fiddle without pulling the lines off the tank)
They were coiled and lying against the jugs. As a result, the hot engine would boil the fuel in the line if it was not flowing, such as being shut off for a short time. One the jugs cooled enough to not boil the fuel (causing a type of vapor lock, I assume) it would start right up.

[Dink]

UMM to offer a different opinion. You may have an intermittent short circuit that is opened by heat, does it turn over when hot but just wont catch? try having a spare set of plugs on hand next time it does this pull the plug caps off and put the other set of plugs into the caps and look at the spark quality then.
Dink

[Anonymous]

Engine won't start after running

Fuel, vacumm, and inline filter are new. There is about 1" of slack in the fuel and vacuum lines from tank to carbs. The engine does turn but does not start. I am sure there is spark at plugs but will double check tonight.

When I set my floats the metal between the floats was resting on the float needle valve at 22mm. On the needle valve seat there is a spring that does not touch the float except when I press it down. This changes the the float measurement to 21mm. Should this float spring be adjusted to the 22mm measurement?

Thanks

[nabrams]

I don't know about the GS550L, but my GS450L is supposed to idle (according the Clymer manual) at approximately 1100 RPM. So when you mentioned an idle of 1500-1700 RPM that immediately makes me suspicious about your idle/mixture settings. If your bike is overly rich it may be OK to start from a fully cold condition, but just too rich once hot.

Also, I had an identical problem on a Honda I had. In that case, it turned out that my spark plug was not tight enough and there was air leaking in at the hole. The leak was just bad enough to affect the bike at a hot start, but not bad enough to affect a cold start.

[Billy Ricks]

Recheck the sync as well. With it having to idle that high they may not be as close as you think. Just barely close number 3 with throttle linkage then adjust the other three to do the same.

[Anonymous]

Engine won't start after running

When engine will not start there is gas in the bowls, plugs are getting spark, tight and dry. The idle/mixture setting is on the lean side. Initially set to 1 1/2 turns out.

Is there any trick to sync the carbs without removing from bike without a vacuum gague? How does the carbs being out of sync effect a hot start?

[Anonymous]

Re: Engine won't start after running

I could be barking up the wrong tree but here's something else to check...
Chain tensioner. I know it might not be it at all but I had an old honda that looked like a hopped up moped (1960's) that did that all the time. I got the manual and started doing some maint. on it and after I retensioned the chain it stopped not starting after it was hot. I guess the chain was getting fairly stretched and the heat was expanding it till it was off time.

Hello everyone.

Having problems starting my 1980 GS550L after it has been running. If I let the bike sit for about 30 minutes it starts right up. The spark and compression is good on all cylinders. When trying to start I can observer gas going to the #2 carb but will not fire on the restart. Cleaned and dipped the carbs yesterday. All the carb o-rings have been replaced and manually sync the carbs. When running, enging idles about 1500-1700 RPMs and good at higer RPM's.

Bike runs good but will not restart and any insight to this problem would be greatly appreciated.