04 YZ250 Questions

Hey all,

Recently bought an 04 YZ250 and I bought the GYT-R flywheel from Yamaha. When I went to put it on, I pulled of the cover and to my amazement saw that there was a bit of mud inside. Upon further inspection of the gasket, it looks as if there is a breather hole cut into it. Is that what this cut out is? Does the flywheel and/or heat create a vacuum and so is needed? Will a small amount of dirt damage the stator points? Just be aware, and maybe make the left side crank case part of your routine maintenance.

Also, do any of you know exactly how much oil I can use in the crank case to maybe cut some of the engine noise down? (I know the manual says 750ml) Is the engine noise normal for this year? This noise is not extreme, but does give me some concern seeing that the bike has only about 5 hours on it. Maybe it is just the normal sound and I am not used to it.

Thanks for any advice.

I cleaned out the dirt and I cut a small piece of a business card, folded in half, to fit over the gasket where the water is coming in. I also put some gasket goo on it. I was just worried that this hole/gap was something that should not be messed with and that is why I was asking. Whew, I feel better now, because I rode it for about an hour the other day like that.

Thanks for the info guys.