gilera jubilee (advert expired)

I have a gilera jubilee that ruins me the candles after little that and in motion it starts to crackle and when he heats all of a sudden well the motor he extinguishes. I try to look at the candle and ago the spark on one side instead that on the electrode, change the candle and he/she normally leaves again.
To this point if you can help to find me the proper condenser there would be thankful, or perlomeno to know that type climbs on because I have changed 2 of them and ago always equal: - (