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1978 XL 100 Rocker arm adjustment !?!?!?

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I've read the manual for hours trying to figure this out but it just doesnt mention it anywhere. The rocker arms have threaded pins in them, with locking nuts, allowing adjustment in the amount of play before the rocker arm pin begins to push the valves down. No where does it mention how much play there is supposed to be...

Before it was taken apart, the bike had a lot of trouble revving up, like the exhaust was plugged up, and upon removing the valve covers the exhaust valve rocker pin appeared to be very loose, so that the exhaust valve was probably not completely opening. Anyone that has an opinion of the proper gap, please impart me some of your knowledge.

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Might be...probably is now that I really think about it. I seem to remember setting them at 1.5 and 2 on my old SL... I was just trying to remember what the book said.

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Ok, I saw those numbers in the manual, I think it said .002 and .003, but it said to measure that gap between the cam lobe and rocker arm. Through the valve adjustment cover I can't even really see the lobe, let alone adjust the gap. Can I just measure it where the rocker touches the end of the valve stem? That seems to me to be the same measurement.

Shawn--Thanks--I have already cleaned the carb endlessly as well as checked the points, timing, cams, ect. If this doesnt work I'm pretty positive there must be some other problem with the exhaust valve, a stuck spring or something.

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The official settings are .002" intake and .003" exhaust. I prefer to adjust them to .003" intake and .004" exhaust as they tend to tighten up with high revs. Be sure to use a lead substitute also as these were meant to run leaded gas. Shawn Mc's settings are probably for a Mega Cycle Cam.

IMO,

Dwight

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The official settings are .002" intake and .003" exhaust. I prefer to adjust them to .003" intake and .004" exhaust as they tend to tighten up with high revs. Be sure to use a lead substitute also as these were meant to run leaded gas. Shawn Mc's settings are probably for a Mega Cycle Cam.

IMO,

Dwight

Powrol...but the real point is lash is lash. As long as the valves are closing and not leaking past the seat, the thing oughta run ok if the carb is clean.

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If everything else fails, remember what the english bike manuals say for clearance:

Light click Heavy click (intake and exaust)thats probably not the problem anyway....

you run those bikes low on oil and the cam and rockers take a crap....check to see if the cam looks burnt or gaulled....replaced a million cams and rockers in early Hondas

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