Cam chain adjustment

xs650dude63

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How far is the pin supposed to petrude when turning over the engine, mine pops out about 2MM past the surrounding metal, should it be flush with surrounding metal, then go back in? Thanks!:)
 
You're probably a tad on the tight side or have a cam chain thats a bit worn too. The pin popping in and out is normal and is just the tension and slack being exhibited as the chain drives the cam. Here's a good video for you to watch.

I usually set mine with the bike running and it s usually got a mm or two of movement.

Many people have different methods too

http://www.xs650.com/forum/showthread.php?t=13058&highlight=Cam+chain+adjustment
 
You can't really see the pin in the video, so I can't see how far the pin pops out, should it pop out past the surrounding metal or pop out flush to the metal then go back in? Or does it not even matter only in and out a mm or two is ok. Hope you understand what I'm talking about.
 
Hi. It really shouldn't pop out at all. Depending on that you of adjuster you have, popping out, normally is attributed to a slightly worn chain / adjusters. As long as as there a mm or two of movement and it sounds ok, you can ride without worry. You'll tune into your bike and what is abnormal.
 
Here is another simple method, that I use. I take the bike out for a short ride to get the engine hot. Once back in the garage, I remove the camchain tensioner nut, and re-start the engine. I use a small 10 mm wrench, to turn the adjuster nut in until there is no motion at all. Then I back out the adjuster nut 3 flats. That's it, shut off engine and replace tensioner nut once the engine is cool.
 
Dude, pay attention to rg's post and disregard the nonsense about your cam chain being overtightened. Excessive movement of the tensioner rod is a symptom of looseness. I know this sounds counterintuitive, but even with a new cam chain, damper, and tensioner, the rod will pop out past the surface of the adjuster if the adjuster is set too loose. Correct tension will limit travel both in and out.
 
Another thing, when turning the engine by hand the rod pops out past the adjuster because as the engine turns over the lobes on the cam are pushing the valves open against valve spring pressure, as the lobe pass over the high point the spring pressure pushes on the lobe.
This moves the tight side of the chain from the front of the engine to the rear, this pushes the pin out past the adjuster nut. When adjusting the cam chain by turning the engine by hand adjust it any where other than when the pin pops out past the adjuster.
When adjusting at this point adjust the tension so the pin is just flush with the adjuster.
I adjust it art idle on a warm engine. I watch the pin an adjust till it comes flush. Some times it's hard to see, I then place my finger tip on the end of the adjuster. I then can feel when the pin comes flush. When adjusting when running you will see the pin move in/out. This in/out movement should be 1 to 2 mm.
Leo
 
Here is another simple method, that I use. I take the bike out for a short ride to get the engine hot. Once back in the garage, I remove the camchain tensioner nut, and re-start the engine. I use a small 10 mm wrench, to turn the adjuster nut in until there is no motion at all. Then I back out the adjuster nut 3 flats. That's it, shut off engine and replace tensioner nut once the engine is cool.

What exacly för you mean with ' 3 flats'?
 
He was talking about the flat spots on the hex end.
flats.png
 
Three flats or five flats or 2 1/2 flats is a fractional part of a turn of a nut or bolt. One flat would be 1/6 of a turn. Referring to the "flat" part of a nut or bolt head.

Here is yet another way of adjusting the cam chain. Turn the crank with a wrench to get all the slack on the backside. Loosen the adjuster with a wrench, then tighten it as much as you can with your fingers alone. This should take out the slack, but not do much more than that. This got the endorsement of a big time racer who chimed in once.
 
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On some of these, the adjuster doesn't turn easily by hand, don't know why. If you do use one of the static methods (motor off) for adjustment, be sure to check it afterward with the motor running to insure there is some rod movement and the setting isn't too tight. This comes right out of Yamaha's shop manuals for their big singles. They outline a very similar static adjustment method (adjust rod flush with end of bolt) but then tell you to check your setting for a little rod movement while idling the motor. I figured there was no reason this wouldn't or couldn't work for our 650s too and well, it does work just fine. I refined the technique slightly in that I don't even bother setting/checking it with the motor off, only with it running.

Someone posted here years back that a long time dealer told him the 4K cam chain adjustment intervals were too much. He said to check and adjust if need be about every 1000 miles. I've made the check part of my oil change routine. With the motor hot and ready to have the oil drained, I check the cam chain first.
 
Yepp i have a big single aswell. And that technique works aswell.

I used rgs tips. Turned it in til no movement then 3 flats out. It got nice movement, not to much and not to less. Would Guess around 1mm
 
On some of these, the adjuster doesn't turn easily by hand,
Maybe just gum cooked on the threads. Mine would only turn by hand cold, not hot, until I had it off and apart once and hosed it with brake cleaner.
 
Hello, reviveing another old thread here.
I had purchased the better / later model cam chain adjustment assembly off ebay, did the comparison to my iriginal 76, yada yada yada, then i looked at each plunger inside the threaded rod part but out of the front plate. With each of the partial assemblies I pushed the plungers to their limits the plunger never fully protrudes much beyong the threaded rod part. Knowing that, isnt over tightening easy to do considering there really isnt an obvious sign of over tightening? You could over tighten a little or lot and it would appear the same, if I understand this correctly?
 
What indicates you've over-tightened it is it's in-out movement stops.
 
I was surprised how mucj force is necessary to get the plunger to reach the end of its stroke and compress the spring fully.
 
That's why I feel the "adjust-while-idling" technique works the best and is the easiest method for correctly setting the chain tension. It's virtually foolproof. Tighten the adjuster too much and you'll see the plunger's in-out movement stop. You can demonstrate this to yourself without damaging anything by momentarily making the adjuster really tight. You'll plainly see the rod's movement become less and less as you tighten the adjuster more, eventually stopping when you get it really tight (too tight). Obviously, don't leave it that way for very long, back it off so you get some movement back. That's actually how I do it. I tighten the adjuster too much so the rod movement almost stops then back it off until I get the MM or so of in-out movement I'm after.
 
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