Loose valves and metal in magnetic drain plug


8 replies to this topic
  • yamaman1

Posted July 01, 2010 - 09:54 PM

#1

I changed my oil today and found a large piece of metal stuck to my oil drain bolt. I have no idea what it is and it measures about 5/8" long by 1/8" wide. Im guessing this is pretty bad even though there is no metal in my oil filter. I also checked my valves and my 3 intakes measured between .011-.012" (not mm) and exhausts were at .010". I shimmed the exhausts to .008" and the intakes to .005-.006", but Im very worried that they were loose. I went from shims 180, 182, 182 to 190, 195, 200 to get them right. I started my bike and it runs fine but I dont feel right about everything. I figured that something was giving me a bad reading so I cranked over to TDC about 5 times each time and shimmed in 3 steps to get to the final pad size. Any ideas? I dont want to blow my bike and kinda want to just put it back the way it was.
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  • thestuz

Posted July 02, 2010 - 03:11 AM

#2

you need to hold it in your hand to give a size indication but it looks like the clutch lock washer tab.
might mean you need to replace it as your clutch retaining nut may come undone.
good luck.

  • 09speeddemon

Posted July 02, 2010 - 05:36 AM

#3

I agree with thestuz One of the locking tabs Have broken off. Now this could be from the clutch basket or could be from one of the other locking tabs. Pull your side case off on the clutch side and check all the tabs Most of the time they only fold 1 out of the 2 tabs so something major could happen if a nut comes loose.

  • grayracer513

Posted July 02, 2010 - 06:39 AM

#4

The piece does look like a washer tab. Open up the right side and check that out.

There are only about 4 reasons your valve clearance would increase:
  • Bent valves (would be accompanied by a drop in compression)
  • Carbon on the valve heads and/or stems holding the valves part way open ( again, a loss of compression would be evident, and the clearance would not likely be uniformly loose across the set)
  • Wear at the lifter face (very rare, usually quite visible, and again, not uniform across the whole set)
  • Seized, worn cams/cam saddles (this is probably it)

Did you notice any damage in the cam caps or saddles in the head when correcting your clearance? Probably a good idea to check camshaft clearance per the manual.

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  • yamaman1

Posted July 02, 2010 - 02:22 PM

#5

Ill check that out as soon as I can. By cam saddles do you mean the cam bearing races? Cam caps looked fine and I did not check the cam lobes. So my cams may be worn out? It it a bad idea for me to ride the bike as is with the thicker intake shims or should I reverse back to the previous shims?

  • grayracer513

Posted July 02, 2010 - 03:09 PM

#6

The lobes could wear halfway off and not affect clearance, since it's the heel of the cam where the clearance is, and it doesn't touch anything.

If the caps look good, and the clearance between cap and camshafts is good, then that's out.

What's the compression like? If it's down, have a leak down test done to see if it's coming past your valves. They could have been bent in a timing chain slip up along the way. If they are bent, they're dangerous, because they are being flexed every time the valves seat, and this can lead to a dropped valve head.

The thing is that there are few things that would cause all of the valves to be uniformly loose. One would be the valves striking the piston. The other is that the previous owner adjusted them wrong. Are you the first owner?

  • MrBlahh

Posted July 02, 2010 - 03:19 PM

#7

looks like clutch nut washer tab to me too

  • yamaman1

Posted July 02, 2010 - 03:31 PM

#8

Compression is really good, nearly exact as a very low hour 06 my roommate just got. Im the 3rd owner of the bike and I can tell for sure that the head has been open at least once, which makes me thing it had been loose the whole time. Ive been riding this thing hard and put nearly 75hrs this year, it is possible that they been loose the whole time? Its always run great except for minor jetting here and there.

  • freerider_australia

Posted July 03, 2010 - 01:45 AM

#9

looks like part of a locking washer the type you bend over you will have to check the manual sound like it may have something to do with cluch. the marks are possibly from screwdriver marks where it was bent clear of a nut





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