what could be wrong?? help.

[ben2306]

k, guys. my gk76a has been running nice for awhile till recently i did a coolant change myself. right after the change, i started up the bike to warm it up. everything is fine. then i decided to bring it out to see the temp but its unable to fire up. tried pushing with a friend few times, the engine seems unable to crank up. tried pull choke no luck. after cranking it for few mins, it gave out a loud fart sound (backfire?? never see flame) @ the exhaust. then i just gave up. but after 30mins, tried again & it started with just 1 press.
same evening, stopped @ traffic lights, about to go, die off, cant start again! parked & waited for 30mins, right after i called tow truck, started again! cancelled tow!
after a week plus, this morning, travel @ highway @ speed around 50km/h, i clutch in & it dies straight! pushed to side, cant start again, had to walk out of the highway leaving the bike there...
what could be wrong? once it dies off, no chance of fire up. had to wait.
okay, there's only something in similar for both incidents, its RAINING...
spark plug got wet? if 1 plug is wet, thought it can still go on 3 cylinders? & i also dont feel any power lost, just straight cut off. battery is strong, just changed. other than coolant change, i never messed up anything. thought it was idling but i've adjusted it to higher rpm.

[ben2306]

okay, workshop showed me a small square black cube with 2 wires, said its a what coil in the engine. anybody with any knowledge what its called? he told me something like "bowser coil"??!
changed that dont know what coil & plug cap rubbers. hope it wont stall & unable to start...

[dobbslc]

Have you checked that there are no loose plugs after you had the tank up?
Check for a kinked fuel pipe as well.

[ben2306]

Have you checked that there are no loose plugs after you had the tank up?
Check for a kinked fuel pipe as well.

i've just changed the pick up coil & plug caps. now its running nice for the time being!