electronic ignition timing

[chopper698]

Newbie here just finished my 74 cb750, I had the carbs rebuilt and im using the stock air box with a 4 into 1 header with a pamco ignition. It starts right up idles no issues, but the bike fails to go over 60mph and wont go over 2400 rpm's, it falls on its face. My mechanic buddy says its my timing and to put a light on it. I put a strobe on it and it was off a hair not much to make a diffrence. I read that after timing it on the F 1-4 to bring the rpms up to 2300-3000 and check the double lines and check to see if it lines up with the line on the case. I did that and the two lines arent even close. I also read im supposed to check the timing on 2-3 after doing the 1-4 cylinders in the same way. Is this info correct anyone?

 

[dirtdigger]

If its not hitting the double marks then your ignition isn't advancing. you need to take apart the advancer and see what is sticking. Ans yes you need to adjust the 2-3 timing also.

 

[chopper698]

Ok I will check it out, what should I look for that would make it stick? So even with electronic ignition I have to time 2-3?

 

[dirtdigger]

The weights should move freely but with the spring tension. The center cam(point cam) should move freely. More than likely the center cam is sticky on the advancer. Yes you have to check timing on2-3 because that is the timing for cylinder 2 and 3. 1-4 and 2-3 are separate systems.

 

[chopper698]

I wish it would have said that in the directions it only says time F1-4 got to 2500rpms check 4 two lines match case line. I thought you only did 2-3 with points.

 

[dirtdigger]

Unless there is something very different with the pamco....I dont know I dont use them. If you check the 2-3 timing is it in spec? Is there a separate adjustment on this setup?

 

[chopper698]

No its just the F1-4. I was searching online it seems otber people have had the same problem as me and it lookd like there is a pin that jas to be grinded off on the advance mechanism.