Doug's xs 650 cafe project

Diego · New Member Joined: Jun 20, 2008 Posts: 2

Hi everyone,
This is my first post on this site. I have read a lot of the forums and am glad to see so many xs enthusiasts who are so knowledgeable about this great bike. This is my first project bike and have some questions.(please see profile pics) I have a 1981 xs 650 that I have been turning into a cafe racer. My question concerns a new oil leak that is coming out of a spout located at the top rear of the engine block. I have a picture of it circled in red on my profile pics. Anybody know what this could mean...It sure doesn't seem good to me. There is a hose connected to this with a small breather valve on it. Any information that anyone can pass on would be greatly appreciated...Thanks...
Doug

JeffM · Posted: May 7, 2009, 9:13 pm Post subject: Re: Doug's xs 650 cafe project

Welcome Diego!

That spout is the crankcase breather.
Hopefully it is just as simple as too much oil in the engine... Mine mists out a fair bit of oil if the level is above half on the dipstick.

jayel · Posted: May 7, 2009, 9:19 pm Post subject: Re: Doug's xs 650 cafe project

yes needs a hose routed to airboxes (if stock air filters, I don't thin' so with those carbies) down and away under the swingarm otherwise, lots of different opinions on breather valves

Diego · New Member Joined: Jun 20, 2008 Posts: 2

Thanks for the quick replies...I did just change the oil and level is right at half...I seem to be losing quite a bit of oil however.....Worst case scenario?

650skull · Support Staff Joined: Jul 19, 2007 Posts: 1186

Diego here is a post TeeCat started on the subject, mite help a bit but then most of us aren't to sure about this..........still finding our way www.650rider.com/index...ply&t=7334

TeeCat · Posted: May 8, 2009, 7:53 am Post subject: Re: Doug's xs 650 cafe project

Welcome!

This may be the post that skull is referring to; his link kept taking me to a "post reply" field for some reason. But thanks, skull, for the referral.

And yes... breathing issues related to oil consumption and displacement/leakage are something that we're feeling out way through. Basically, though, it seems that these engines are designed to operate with a modicum of crankcase vacuum in order to minimize oil expulsion from seals, case joints, and gaskets.

I'm just learning but will help if I can.

TC

Retiredgentleman · Posted: May 8, 2009, 11:12 am Post subject: Re: Doug's xs 650 cafe project

Crankcase pressure or excessive oil out the breather probably means the engine has high mileage and things such as rings and valve seals are worn. Compression or leak down test would be the next thing to do.

650skull · Support Staff Joined: Jul 19, 2007 Posts: 1186

Wouldn;t have a clue as to what i did on the last post...........Must be the drugs, Can't drink alcohol Laughing

..........here i tried again and checked it this time Wink

www.650rider.com/index...viewresult

tintin · Full Member Joined: May 07, 2007 Posts: 96

Got more pics of your bike? Looks like you have extenders on your carb mounts?

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Yamaha xs650