Hot Start Problem

[johnod]

Took the bike out on Sat, started fine from cold.
Drove into town, stopped at bank, wouldn't restart, barely turns over, till it cooled down, 20mins maybe, starts right up.
Never did this before.
Any ideas as to the cause, and how I can test for the problem?

Thanks

82 Kat 1100

[gsrick]

Took the bike out on Sat, started fine from cold.
Drove into town, stopped at bank, wouldn't restart, barely turns over, till it cooled down, 20mins maybe, starts right up.
Never did this before.
Any ideas as to the cause, and how I can test for the problem?

Thanks

82 Kat 1100

My 78 1000 used to do that until I replaced the starter.

[johnod]

Thanks

I kinda figured either that, or coils.

Was hoping someone else would weigh in too.

[TxGSrider]

Thanks

I kinda figured either that, or coils.

Was hoping someone else would weigh in too.

I wouldn't think it as the coils, because that might make it difficult to start but shouldn't have any effect on how fast the starter spins the motor (in fact it might spin faster if the coils were a problem). So its probably a starter or battery issue.

[earlfor]

I wouldn't think it as the coils, because that might make it difficult to start but shouldn't have any effect on how fast the starter spins the motor (in fact it might spin faster if the coils were a problem). So its probably a starter or battery issue.

I'm thinking most likely a faulty battery causing the problem.

[salty_monk]

Have you done anything with the coils recently? It could be a symptom of them being wired backwards (spark then jumps the wrong way), can’t remember if that’s possible on a GS but it’s a hot start symptom on old cars...

[KEITH KRAUSE]

Like Earl said, battery. I'd check the battery condition first. A battery with low voltage will struggle to crank the motor, especially when hot.

[hampshirehog]

If the battery checks out I'd suggest looking at the starter motor bushes and armature. Symptoms are classic for those being worn or dirty.

[Steve]

Have you done anything with the coils recently? It could be a symptom of them being wired backwards (spark then jumps the wrong way), can’t remember if that’s possible on a GS but it’s a hot start symptom on old cars...

Does not matter if it's possible or not, or even if it does actually happen.

There are two leads on each coil. The coil is actually in the center, electrically, with one wire going each direction. That means, for example, that on #1, the spark will jump from the center of the spark plug to the side electrode, but #4 will jump from the side electrode to the center. Reversing the direction, as you suggest, will only change which spark jumps which way, but normal operation on our bikes will have two sparks jumping in one direction and the other two sparks jumping in the other direction.

.

[johnod]

Thanks for input, was away for a few days.
Nope no change on coils, will check starter.