Question about 1970 Honda CB 100

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Right now its not starting. popps through carb. seems to be out

Of time.cant seem to be able to time it.plug , points coil all new . have timed it in the past by eye ( no light ) ran fine also having tough time feeling cam chain with adjuster. I still think its a timing issue . 3100 miles great shape please help. thanks. Toots p.s. cleaned up carb new float and gaskets

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  • joe May 11, 2010

    points are gapped properly?

    tang on new carb float is adjusted properly?



    timing by eye should get you very close.

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Check camshaft wear in cylinder head not excessive. ignition contacts should be set to .012" (no wider).
chech valve clearance EX .003" IN .002"

Posted on Apr 13, 2009

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Its easy to time it, remove the side cover to see the megneto there you will find the timing marks T and F aligne it to T and thn remove the spark pulg to feel the piston if its on TDC (top dead center),
remove also the point plate and the rotor assy you will come to the camshaft sprocket ..there too you will see marks on the camshaft gear which should be to its mark on the head.If they align tht means the timing is ok i.e the valve timming , now u will have to set the igintion timming , by refitting the point plate and adjusting it clockwise or anti clockwise, set theengine to be on the firing stroke and get the plug out thn turn the engine keeping the igntion 'on' you should see sparks at the spark plug as the piston is going downwards.

Hope this helps!

Knight.(Yamaha Seca XJ750A 1981)

Posted on Mar 04, 2009

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