cam position force 125 1988

[fisheymikey]

here are some pics no matter what I do I cant seem to get it right...

I listen to the link and sink but getting the screw in the middle of the scribe lines with the buttleflies open is impossible.

these pics are the best I can do...

what im I doing wrong

mike

 

[Frank Acampora]

Re: cam position force 125 1988

NONSENSE! I can see from the photo that the roller is way forward.

NOW: Having the roller centered between the lines is just a STARTING POINT. You disconnect the ball link and set the cam so the scribed lines are straddling the black roller with the carbs fully closed. THEN, you turn the screw until the roller is JUST touching the cam.

Then you open the throttle to wide open and set the ball links so the butterflies are substantially horizontal and clip the ball link back on.

Once the engine is running, you set the idle speed using the idle stop screw. Idle position will most definitely NOT be with the roller between the two scribed lines--in fact it will probably be right about where your photo shows.

 

[fisheymikey]

Re: cam position force 125 1988

I feel less stupid now...

the only confusing part is setting the roller.

does the cam need to be relatively horizontal? because I could set the screw almost in any position to start with your explanation.

Frank I don't want to get on your bad side I already have experienced the severity of you're explanations. feel im back in high school afraid of my teacher.... hahaahahha

mike

 

[Frank Acampora]

Re: cam position force 125 1988

The severity of my explanations varies directly with how much Rheumatoid Arthritis is acting up. Sorry--can't help it, I get crabby when in pain

You simply loosen the nut on the eccentric screw a bit and turn the screw until the roller is tangent to the cam between the two lines. You eyeball the two lines and set the roller.

Remember: The sole purpose of this adjustment is to ensure that the cam is just touching the roller with the carbs snapped closed. This SYNCHRONIZES the opening of the carbs correctly. It is NOT a running position since carbs must be cracked open slightly and timing advanced a degree or two at idle.

 

[Jiggz]

Re: cam position force 125 1988

"It is NOT a running position since carbs must be cracked open slightly and timing advanced a degree or two at idle."

This statement by Frank is very important especially in your case. It means if your engine is already capable of starting and idling, the cam's two lines should not align with the eccentric screw slot anymore because you now have the throttles slightly open and timing slightly advanced. When the cam's two lines and eccentric screw are aligned (initial settings, meaning you have zero idle screw setting), unless control handle is in fast idle, the engine should not start nor idle because the throttles are fully closed. In short, from the initial setting of zero idle the cams and eccentric screw should align and then set the idle settings (800~1000 RPM on muffs) which advances the cam and timing thus the the cams and eccentric screw do not align anymore, normally.