Oil Leak??

[WORCSYFZ199]

Hey I was wondering if any of you guys have had this problem, I have an 04 YFZ and when I run it it leaks oil from behind the front sprocket and it leaks down and drips from my chain and down to my engine/chassis skidplate . I was wondering how you would fix this, is there a seal or something worn out behind the sprocket on the shaft? any help would be greatly appreciated. thanks

[MJNOVA]

There are two seals ---a o-ring and a standard round one.

Take the sprocket off then the half cover.

You will then see a sleeve on the shaft---wiggle it off. under it you will find the o-ring---mine was leaking there. I also replaced the stadard round seal for the shaft---it is right there and can be done on the bike also.

I saw zero tears in either but it stopped the oil leak.

[WORCSYFZ199]

Thanks for the info, by half cover do you mean the whole engine cover? and what parts do I order the O-ring and the shaft seal? thanks again

[MJNOVA]

O-ring and shaft seal. The cover is the small -thin metal cover that resides behind the countershaft. It is held on by 2- 8mm bolts--

The repair will take about 5-10 minutes max.

[WORCSYFZ199]

Awesome thanks for the info, did you drain the oil first or would you recommend it? I am do for an oil change anyways but was wondering if thats necessary

[MJNOVA]

If you turn the bike on its side there is no need to drain the oil. Be VERY careful to put the round seal in staright. Use a large socket of the same diameter and tap it in slowly. Look at the orignal one before you remove it to see the placement.