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Discussion Starter #1
Hello everyone.........i am the new owner of a 99 600 dark with 2000 miles on the clock. Since getting the bike i have felt that the motor sounds a bit "tappety".......i set out to check the clearances but hit on a few problems. Firstly with removing the sparkplugs to ease the job of turning the motor over, the supplied plug spanner or the ones in my normal tool kit would not fit (they are NGK's). Secondly the Haynes manual obviously tells you to check the clearances at TDC.....i know there is a site glass on the left side of the motor, but which marks are which?.......i can find no mention of them in the Haynes. The closing rocker clearances do seem way above the optimum.....could this be the noise i am hearing? Lastly on having a quick look at the belts they seem plenty loose enough to me.......i can comfortably twist the belt 90 degrees and pull it clear of the tensioner pulley with my fingers so that you can see daylight.
As you may have been able to tell i am from the UK, i hope you dont mind me jumping in on your forum. Have a good day!! :)
 
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On my M750 '02 there are 2 marks, one is BTDC (BeforeTopDeadCenter) and the second is TDC, when you turn clockwise. Remove the valve covers, turn the shaft clockwise many times to get use to the movement of the opening rockers, at TDC they are both high and you should have the marks aligned. The "tappety" noise is normal when cold, not "normal" after 15 minutes or so, clearances on the closing shims are too tight, valve kicking valve seat hence noise. Check if you can rotate the closing shims with your fingers, at least. If not replace with smaller shims, or sand them down a bit.
 

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NGK "D" family spark plugs are normally with 18mm hex. champion or crap plugs are 16mm or 5/8".

the method i go about to check valve clearances is to check them at TDC. remove spark plugs then valve covers. observe the cylinder you're about to measure... rotate engine and watch intake valve go down (open) then come up (close). now that cylinder's piston is on its way to TDC. i insert the end of a small flexible flashlight into the plug hole and watch the piston come up and more or less "stop". then i check the timing window. there are 2 marks near TDC. TDC and "Fire". it really doesn't matter where these marks are in relation to the pointer, as at either, you are supposed to have same reading. the valves are not doing ANYthing ANY time near TDC before or after. they must be shut in order for the engine to compress the mixture or to get work out of the burn after the spark plug fires.

NOW... you will coincidentally note that when the rear cylinder is at TDC, the marks used for setting the belt timing are now aligned. (well, i think it's the V cylinder... could be the H one, eh?) here, you will notice little raised dots on the inner belt covers that will more or less line up to dots on the belt pulleys. and in the V of the engine, there is a notch in the engine cover that aligns with the dot on the drive pulley.

given how "gross" the movement is between "teeth" of the pulleys, this makes for a pretty good method of indexing the cams to the drive pulley.

when i perform a valve adjustment, i will remove the belts after the clearances are checked. this makes it really easy to move the cam in order to get the opening rocker arm over. it also makes it REAL easy to keep the piston at TDC for the cylidner you're adjusting. real hard to drop a valve into the cylinder when the piston is in the way.

:) chris
 
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Discussion Starter #5
Actually, there are three timing marks per cylinder on the flywheel. The engine turns counter-clockwise ( same direction as the rear wheel ) While rotating the engine, after the intake valve closes the first mark to come up is the timing mark at 32
degrees BTDC. This is the full ignition advance. As you continue rotating CC-wise ,an inch and a half or so later you'll
see two dots close together. The first (left ) is 6 degreesBTDC. This is the ignition idle advance mark. Which leaves the last one as TDC. As Chris pointed out, when the horz cylinder is at TDC, the pulley timing marks are lined up.
Hope this helps ;D
 

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Chirs has a great point about removing the belts when adjusting valves. I personally think it's much easier to turn the valve train by hand using the cam gear and not worry about where the pistons are. Ducati has a tool for doing this, but you can do it by hand without much effort. Telling when the valves are closed isn't hard and you'll get the feel for it. Valve adjustment is done when the valves are closed which is a function of being at TDC +/-. Be sure to line up the index marks when re-installing the belts. The horizonal cylinder is a little trickey to line up as it's in mid stroke. Belt adjustment isn't hard nor does it need to be exact.

Valve adjustment on these things is sort of an art, but once you've done it a couple times it isn't hard. Be patient, take your time, and don't drop a valve into the cylinder when you remove the wire collets (stick something in the spark plug hole to keep the valves in place). The horizontal cylinder is a snap. The verticle one requires a little more effort.

There is some disagreement as to valve clearances and Ducati has altered their "factory specs" somewhat. The Haynes manual specs are good for most. Have fun.
 
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