Cam chain tensioner blade clip? what is this?

[andrsn]

Hey, I'm putting my engine back together but before I put the cam chain back on can someone tell me what this little square shaped clip does? It's located on the bottom of the cylinder head right about where the adjustable cam chain tensioner blade sits. Does my cam chain tensioner need to slip inside this thing? If not, what is it and why is it there? (not my picture, stole it from another thread on here)

 

[TwoManyXS1Bs]

That's an oil breather baffle. If you do a search on "baffle", many threads will pop up covering that...

 

[Wanderer]

Thanks for your quick help!

 

[CDNTX650]

Remember to remind yourself to put it back in....then forget...then remember after the engine is in and you have been riding it. Not like I know from experience....

 

[angus67]

Remember to remind yourself to put it back in....then forget...then remember after the engine is in and you have been riding it. Not like I know from experience....

I did the same.....still sitting in my tool box full of metric fasteners, and things proprietary of the xs, like the rotor puller .
Its just a baffle so more oil mist collects and drips back down in the engine, instead of out. But if the oil level is right, with or without, it doesn't matter. If you have too much oil, it will blow out there.

 

[CDNTX650]

Yeah I haven't noticed anything either.

 

[rpmalerba]

Hi guys, new member here.
I joined to give a big thank you for this post about that oil clip.
I just put my top end together today and found that clip on the floor.
I almost died. I had no idea what it was, but now I do.
It'll not be going in.
Took me an hour of digging to find this post. I'm so happy I did.
thanks again for your time and help.
I picked up a 79/80 special 2 with 4k miles and rust.
The motor was frozen but i freed it. One piston at 957 had a stuck ring and one bent valve.
I got all the used parts on eBay along with 2 carbs.
Hope to have it running tomorrow.

 

[angus67]

Right on!! One of the very few things needed if properly maintained

 

[rpmalerba]

Got it running today with the eBay used piston, valve, and carbs.
Sweet ride.

 

[angus67]

Cool. Pics?

 

[rpmalerba]

I will post some when at home on laptop.
I was looking for a project and I certainly found one. I bought it on Craigslist in Connecticut for $200. The gas tank on it originally was smashed and had about 3 pounds of rust in it. But it did come with a spare tank. The motor was stuck but I freed it with a wrench on the crank then I took the head and jugs off and found one stuck valve and one bent valve and one piston with the rings stuck inside. No matter how much time and energy I spent I could not free the top ring from that piston. So I found an exact 957 on eBay. Basically new gasket kit and reassemble it and it runs beautiful. I am having a problem trying to get the tappets quiet when it heats up. I've read a lot of threads but for some reason no matter what gap I use I can't seem to get it quiet? So I guess I'm going to maybe adjust them when it's hot instead of cold. The bike basically should have been junked so, it's good to say I brought it back to life. Only 4000 miles, but unfortunately rust on the frame etc so I'm going to be forced to spray can it. The seat is in excellent condition I'm happy to say, and both rims are decent chrome. Mufflers OK condition too. One carb was shot so i bought a pair on ebay and swapped parts. Basically a nice old classic.

 

[gggGary]

2m covers this issue extensively here

The short version is set the tappets cold, let it rattle some unless you are willing to do the top end.

 

[5twins]

You didn't mention the cam chain. If it's set too loose, it can rattle just like loose valves. You can test for this by adjusting it while the motor is idling. If the rattle goes away as you tighten the adjuster, you "fixed" it. Just don't make the chain too tight. Watch for a little bit of in-out movement on the plunger in the center of the adjusting screw. If it stops moving, you've set it too tight.

 

[rpmalerba]

Thanks for all the great replies. Here are some pics. Thanks again

 

[rpmalerba]

You didn't mention the cam chain. If it's set too loose, it can rattle just like loose valves. You can test for this by adjusting it while the motor is idling. If the rattle goes away as you tighten the adjuster, you "fixed" it. Just don't make the chain too tight. Watch for a little bit of in-out movement on the plunger in the center of the adjusting screw. If it stops moving, you've set it too tight.

I adjusted the cam chain as per the threads. Pretty sure its correct. Thanks.

 

[rpmalerba]

2m covers this issue extensively here

The short version is set the tappets cold, let it rattle some unless you are willing to do the top end.

WooooW. TMI. My brain could never handle all that info. I love the short version. Just to be sure, you advise what gap cold on which side? 2.5 intake and 4 exhaust for the 79 special2?
Thanks?

 

[gggGary]

2.5 and 6 I believe.

 

[rpmalerba]

6 would be even louder than the 4 I did.

 

[gggGary]

6 would be even louder than the 4 I did.

Maybe. I don't know that it's proven, but your flat blade can't measure the clearance in the grooves or pitting on tappet or valve stem. BUT since there is possible lateral movement between the two, if you DID tighten to some "at this time" clearance then movement changed the relation you could conceivably burn a valve. AFAIK .006" is the minimum exhaust clearance spec'd for any year.

 

[gggGary]

FWIW I have considered jigging up a dial indicator to set valve clearance but the above mentioned lateral movement may make that a risky technique.... A bit of valve clatter is just part of the charm....