2004 Suzuki GS500F doesn't start/cuts out at low revs when wet

[HomerPlata]

I parked the bike outside work the other week, in the rain, and when I came back to it that evening it wouldn't start. The battery was fine, the starter motor was firing just fine, but the fuel wasn't igniting.

I initially solved that problem by buying a bike cover, and now it successfully starts for the journey home no matter what the weather is like.

I assumed this was purely an issue with getting the bike initially started. WRONG.

Came to the end of the motorway a couple of days ago (after 30-40 mins of heavy rain), changing down gears as I approach the roundabout, dipped the clutch as I dropped into first gear and coasted a little bit towards the line. Off goes the engine.

I got it started again by putting the choke back on partially, and had to leave the choke on for the remainder of the journey or it was cutting out every time the revs dropped.

Any advice, or obvious diagnosis you can share, based on the symptoms? Any gut feel for the cost estimate of fixing?

Tar.

[fastbob]

If they are detachable from the coil (s) I would try replacing the HT leads and possibly the plug caps while you're at it . Could be shorting in the wet .

[HomerPlata]

Thanks Bob.

[Fozzie]

Are the plugs getting wet?

I had an SV650 that would drop the front cylinder out in the same way you describe.

Fender extender, and grease up the spark plug caps and HT leads well to stop water running down them. Stops water being thrown up by the front wheel and working its way down the HT leads

[HomerPlata]

Thank you sir