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Discussion Starter #1
Much has been written on this so I won't repeat the detailed procedure. There seems to be some amount of confusion regarding when the engine is exactly at top dead center on the compression stroke and what mark should be in your inspection window. There is no need to even look at the inspection window. There are over 180 degrees of crank rotation where you can adjust your valves. You just can't adjust the valve when the lifter/rocker arm is engaged on the part of the cam lobe that is opening the valve of interest. The rest of the rotation is on the heel or base circle of the cam and there is no lift (valve is fully closed and can be adjusted). How best to find this "no lift" sweet spot? Easiest way I've found is to adjust the Intake valve lash when the EXHAUST valve begins to open, this will assure that the intake valve is on the heel of the intake cam lobe. Adjust the Exhaust valve when the INTAKE valve has just closed . It's that simple. You can turn the engine with a wrench as described in the previous posts or just use the rear wheel. I turn the engine by getting the rear wheel off the ground, pulling the spark plug and putting the bike in 4th gear. Now turn the wheel (forward direction) until the appropriate valve described above is opened or closed. In all cases you need to be turning the engine in the normal direction of rotation. Hope this is helpfull.



Scott
 

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Whatever works for you is always the best way to go. I like this method because it's faster for me. Only need the valve covers off which all methods require. On the logic, take a look at any automotive cam on line. The duration of the lift or "lumpy" part of the cam will typically be around 230 to 270 degrees. That leaves around 90 degrees of cam rotation at zero lift where a valve can be adjusted. Your crankshaft turns twice for every rotation of the cam, so that's about 180 degrees of crank rotation that are fair game for adjusting the valve. Please forgive me if I'm telling you what you already know. Not trying to sound like a know it all because I'm definately not. I'm just a nobody who loves working on bikes. Then again, nobody is perfect
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Whatever works for you is always the best way to go. I like this method because it's faster for me. Only need the valve covers off which all methods require. On the logic, take a look at any automotive cam on line. The duration of the lift or "lumpy" part of the cam will typically be around 230 to 270 degrees. That leaves around 90 degrees of cam rotation at zero lift where a valve can be adjusted. Your crankshaft turns twice for every rotation of the cam, so that's about 180 degrees of crank rotation that are fair game for adjusting the valve. Please forgive me if I'm telling you what you already know. Not trying to sound like a know it all because I'm definately not. I'm just a nobody who loves working on bikes. Then again, nobody is perfect
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The method you described is exactly how I've always set valve lash on car motors. I suppose I never tried to apply it to my motorcycles. The way I remember it is EO-IC. Exhaust valve starts to open set intake, intake valve starts to close set exhaust lash. It always worked on my race motors.
 
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