Trouble with Valve gap Changing

Kathos

Kathos

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Anyone have issues with their valve gap changing? I notice when i set my valve gap (cold of course), Ill set it to .003 & .006. Manually crank it around a few times to check.
When I start riding the bike, it will sound nice and quiet. After I ride it a couple times, it always starts getting clanky.
When I check my cam chain tensioner, it bobs a little like it supposed to. Then when I check the valves, the gap increases to like .011" on the exhaust and slightly on the intake.
When I adjust them again, the lock nuts are still tight. After I adjust them, the same thing happens again?
I dont think they are coming loose because the nut is still tight so what is happening?:wtf:
 
Check the adjuster by removing and looking at the tip.

Then examine the end of the valve for the contact area.

One or both are deteriorating.

Not uncommon.

Hopefully the valve is okay and you can replace the adjuster.
 
Okay, I looked at them last time I took them out. They didnt look too bad to me. Here are some pictures.
 

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Not what I like to hear. Would new adjusters remedy this or do I need to replace the valves as well.
Something tells me that the old valves would just damage the new adjusters.
 
Yeah I saw that in the link you posted. The guy noted that it made is engine clatter worse. Did you experience the same results?
 
I haven't installed any elephants foot adjusters yet. Read a lot about them, researched other sites, bought some for analysis. They'll go in when I overhaul.

Mixed reviews on the noise, most seem to lean toward 'quieter'. Condition of related parts, valve lash, oil type, and operating temperature would be strong influences on the results. Guys have been running them for quite awhile now, even longer on VWs and Porches, so I'm pretty sold on them.

Except for the precision machined and expensive Porche adjusters, there's a couple quality issues about some brands...
 
TwoManyXS1Bs said:
Looks like the adjuster tip is going flat, and the valve tip in the last pic looks cupped. Here's a similar scenario:

http://www.xs650.com/forum/showthread.php?t=28536
Click to expand...
That was my thread that TwoMany referenced above.
I guess I already removed the pictures of my valve stems that were originally in post #11 of that thread, but imagine valve stem ends that are completely fractured.

Anyways, unfortunately you need to replace the valve or valves that is making the noise. Your third pick looks fine. Your fourth pic looks like a big piece has fractured off. A real shame. About as bad as previous owner abuse can get is setting the gap too small which causes the hammering that causes this.
 
@DogBunny, Im not sure whats going on with the picture, but from what I remember, all the valves looked pretty much the same with that slight divot. I dont think any of the tips broke. If all that valves look like the third pic, is that acceptable? New valves seem to be smooth on the top.
@Mrriggs The retainers look like that on all of them. It never occured to me that this is incorrect?
 
check the cam I have a buddys bike here right now with a wiped cam it was doinf the same thing I hope it's not but it's something to check.
 
Kathos said:
@DogBunny, Im not sure whats going on with the picture, but from what I remember, all the valves looked pretty much the same with that slight divot. I dont think any of the tips broke. If all that valves look like the third pic, is that acceptable? New valves seem to be smooth on the top.
The end of valve stem #4 still looks like a big flake has chipped off. It's hard to tell because the pic out of focus. A good end should basically be flat, like the one in your pic #3 seems to be, again hard to tell from the pic.
Click to expand...
 
Last edited:
I need to look into this more but the previous owner rebuilt the engine. He bought 2 intake valves(01-9091). 2 exhaust (01-9092). Valve spring set shim(05-0028). Performance spring set (05-0029). Stem seals(01-0114). And new tappet screws and nuts(01-9095).
I know the performance springs can only be used with certain valves, maybe this is the issue?
Edit
From MikesXs
"Performance Valve Spring Set (8 pc.) with steel caps (4 pc.)
Special Valve caps provide maximum Cap to stem seal clearance.
For use with the XS Performance #05-0025 Cam or
Web cams or to replace original stock spring & cap sets.
Fits: XS/TX650's 1970-84. "

So it seems like the springs can be used with any combo. Doesnt look like the parts are miss matched.

Can we talk about if the valve retainers are too deep or correctly positioned?
 
Last edited:
I've never fooled with those. I suppose the internal taper of the cap could have been opened a little so that the cap base sets higher off the guide seal, and gives that 'recessed/pocketed' appearance on top. Somebody else will have to comment on this...
 
The spring retainers look like the light weight type that have a different profile from stock.

I'll open one of my valve caps later today and take a picture to show you.

Looks like too much wear on the contact areas for a new rebuild.

This will not be an easy fix. or cheap.
 

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