Yamaha Aerox engine stops in rain...

Hi all.

So i have a 100ccm aerox and so far im loving it. Except it has a habit of simply stopping in rain. The symptom resembles a loss of ignition. If i wait few minutes it starts up again. And here comes what puzzles me. If i dont go above ~50 km/h it wont happen no matter how heavy the rain is. The service couldn't replicate it so they changed out the transformer, cable, spark plug connector, and the rubber "bell". But it didnt helped...

Currently im looking it up how this baby comes apart(and some way to get bigger splashers onto it) but i would like to get some help with the diagnostics part.

Thanks in advance .

 

Does it have the standard airbox or an open cone type air filter?

 

I think its the factory original. It connects to the variator housing...

 

the factory air box on them is prone to flooding being so low down
Make sure it’s properly sealed

 

I tok it apart but i didnt see any water ingress residues. And experimented a bit:

(Forgive my poor english in the vid, plus this is my first time making this kind of video so its kinda crappy... Oh and dont worry about the paint sprayer, its a dirt cheap crappy one i keep for stuff like this.)

 

Okay, we had a nice long rain at night and i forgot to cover the poor thing... It was wet all over the the place(only the treadle and knee piece left on) but it started right away.... Ill try soaking it even more with the hose.

/UPDATE
I finally managed to reproduce it, all it needed was a good spray with the hose where it sucks the air in to cool the cylinder. And it doesnt seem to be electric:

Plus the spark plug and the inside of the rubber "bell" is dry...

This is one hack of a mystery....

 

Why does it sound so much like its not got an air filter? Sure sounds like water in the fuel to me.

 

I also sprayed a good amount of water onto the carburetor and the air filter intake but didnt do much. Spray into the cooler and in a few sec it given me the above issue. And it had the air filter on the whole time(maybe i pulled a full gas when it stopped, idk). Just to be safe i will empty the gas tank and the carburetor on the weekend.

 

There goes my idea about the electric system.... I also sprayed the carburetor and the filter from above like this and it stopped. Is it possible that the water is getting to the air intake from the rear wheel because of the absence of a mudguard? (Or maybe form the front wheel? The belly plate usually full of mud after a rain....)