damhugs

Brilliant, thanks for the responses! Will check this out the HT leads and spark plugs today. I'm on Koh Samui.

I have a customised bike with a lifan 250 engine. Had quite a few problems, most recently a vacuum leak from the carburetor causing to splutter and stall when the revs got too high. Thats now been sorted and has been fine since. Over the last week though every time it rains it has started doing exactly the same, spluttering and stalling as soon as it goes through a puddle or gets hit by same rain. Only when it rains though, it is absolutely fine otherwise. Any idea what this could be? I live on a small island in Thailand and most mechanics don't have the intuitive to investigate the problem so I need a point by point of what they should look at/change/fix. It is also rainy season so as a daily ride getting to work is quite a challenge when the bike isn't behaving its in the rain. Cheers!