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How do you tell when your valves need to be adjusted? I took it in when I hit 18,000 miles and they where fine its a 929 01 help a brother out..
 

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If they're getting loose then you'll get sick of the topend rattle but if they're getting tight the signs are far less obvious. A rise in exhaust gas temperature may indicate tight exhaust valves but really by then the valves are probably already burnt.
By far the simplest way is simply to check them regularly and record the changing clearances so you can extrapolate to when they'll be getting close to the limits.
As a general rule if your cams sit directly over the lifter then the clearances tend to tighten up as the valve stretches faster than the cam lobe wears. With rocker arms it's normal for them to loosen due to the numerous points of wear in the train in addition to lobe wear. There are exceptions though due to various materials and manufacturing techniques.
Checking the clearances is easy. Remove the tank and airbox and then the valve cover. Turn the motor to set the first eight valves away from the cam lobes and poke progressively thicker feeler gauges between the lifter and cam or rocker until you find the thickest that'll fit. Turn the motor forward (never turn a motor backward due to the risk of the camchain tensioner backing off) until the other eight valves are away from the lobes and measure those as well.
Usually you can swap around the sixteen shims you already have to get most of the valves right and then just buy (or swap with your local dealer) the few you need to finish the job.
When you've replaced the shims turn the engine over a few revolutions and check the clearances again.
A good tip is to write the current shim sizes on a surface near each lifter (or inside the valve cover) so that you can calculate the shims you need to buy without having to remove the cams first to pull the shims for measurement.
I always measure shims and feeler gauges with a micrometer for accuracy.
When removing the cams to get to the shims always undo and retighten the cam holders progressively. The camshafts may be cast iron but they will break if you load them unevenly.
 

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Good point that I should've mentioned. Any bolt that affects oil clearances needs to be correctly torqued.
 
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