HEADS UP!!!

Site upgrade in progress... Core site functions are working, but some non-critical features/functions will be temporarily unavailable while we work to restore them over the next couple of weeks.

Please post any bugs you encounter, but before you do, check to see if it's already listed.

Thanks for your patience while we work to improve the community.

Sign in to follow this  
Followers 0
Anssi

-03 YZ450F oil piston ring installation

5 posts in this topic

Hi,

I´m doing some maintenance and can´t remember how the corrugated oil scraper (that has the two thin rings in the same groove in the piston) goes in. I know it has to go in before the accompanying rings because of the notches and that the ends should not over lap. However, I don´t remember whether it matters which way the ends point, up or down?

So, _/gap\_ or \gap/ ?

I thought the manual had a picture of this, but the pic must´ve been in the instructions for the big bore kit that my dad got for his 450 and is now lost.

Share this post


Link to post
Share on other sites

I'm not sure I understand your question entirely. There is no right side up, upside down on the oil ring expander. Put the expander in, and butt the ends together. Do not allow them to overlap.

The rails, or scrapers, must sit above and below the center of the expander, against the small ledge on the inner diameter with their end gaps located way from the other gaps in the oil ring. Refer to the manual for the correct ring end positions, and note that in the illustration, "d", the "oil ring" refers to the end of the expander.

Share this post


Link to post
Share on other sites

Grayracer the ends of the corrugated ring are like a "V". I think Anssi possibly means should the "V" point up or down. Does it make any difference?

Share this post


Link to post
Share on other sites

Odd. Normally, the expander ends would butt squarely when viewed from the side of the piston. If there is any kind of paint mark, etc., on one side or other of the expander, and no instructions to the contrary are in the ring package, I would assume that to be the top of the expander. Otherwise, check with a dealer tech, or take your best guess. It shouldn't make a big difference, but they must have had something in mind.

Share this post


Link to post
Share on other sites

Yes, what I mean is that the end do indeed point up or down (so if you flip the ring, it will not look identical (where the ring continues, the horizontal parts of the ring will be either on the upper or the lower edge of the rim, so johnmeasures figured out what I meant)). I thought it makes little difference so just put it in and it runs great.

I did position the end gaps as per the manual and did remember(have done 2 YZ450F top ends before) and check from previous posts that the ends should not overlap.

Thanks for the help, guys.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0