Help! What's this? (with pic)


XS650 Enthusiast
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Calgary, Alberta Canada
Took my filter out the other day and found crystalized black pieces in it.
Any ideas?:wtf:


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The picture resolution isn't good...but from your description I would guess that it's the cam chain tensioner/guide....


Guide Stopper (Front cam chain guide bar) Fits: All TX/XS 650's 1970-84 - OEM Ref.# 256-12231-01 When black plastic bits start showing up in your oil its usually from the guide bar breaking up due to heat & old age. Replace it as the cam chain will next start to saw its way thru the aluminum support.

OEM Reference #
- 256-12231-01

....the above from Mike's XS
It also means your sump filter has a hole in it. That's normal, no worries but you should fix the hole in the sump filter so the oil pump doesn't have to grind up the bits you see in the side filter. There are about 50 threads on fixing or replacing sump filters.

That means sooner or later you need to do the front cam guide, engine out of frame, head off, to get there. But the thin edges of the guide rubber often break off long before the center part is worn out. It's a bit hard to see the guide unless you tear down the engine. If you see aluminum show up then you KNOW it's time to do the cam guide.

Some pics of a typical used guide and a new mikes guide, notice the quality of the threads
Also pics of sump filters, OEM with typical torn section, Mikes filter, and Mikes filter with a splash guard installed because I have heard the mike's filter will tear also.

paint 001.JPG paint 004.JPG

paint 010.JPG tappets 003.jpg

Very helpful guys, thanks! Is the cam chain guide something I should be doing immediately? The sump filter I will obviously take care of right away.

I do love this forum!
Change the oil, fix the filter and run another oil change or two to dsee what else comes out. Seriously if you aren't seeing aluminum yet.....
unless you want a full riding season with no down time. Not to say it won't last another 5K miles either.