I have a 01 300ex with a stock motor that runs great. You can put it in neutral rev the bag out of it and it sounds great. When out riding it sounds great until the motor lugs down then it will tick. I know a lot of the ex will make a tick sound. But mine only does it when it is lugging down. The only thing I can think of is the valves may need to be adjusted. But it is not a constsnt tick. Any input would be great. Thanks!