‘78 Special - timing issue?

Duck749

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So I was able to replace cam seals which meant pulling advance and point assembly off. Marked timing and reassembled. When going to start bike and check for leaks it just cranks with occasional “gun shot” and flame out one exhaust and no start or running.

The advance was all keyed which makes me believe this is just a timing issue. Is there a specific advance setup and assume I should just do normal timing verification correct?
 

Jan_P

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It was a log time since I had points
I would check that the advance unit is operating properly pulling back to retarded position
then I would check the points installation gapping and check that no short circuit and then timing.
Shooting in exhaust is to late ignition usually
 

Duck749

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So I did confirm tonight that advance is off, will this alone cause similar issue?

Don't forget this little detail....

atu7.jpg


There are two locating pins on the advance rod that can be installed in one of two ways. The slotted disk on the advance can be installed in one of two ways, so that's three things that can be 180 deg. wrong, but if two of the three are 180 out, then no problem because 180 + 180 = 360. :thumbsup:

So, if you think that you have one of the three 180 out, don't worry about which one it is...just flip any one of the three 180 degrees and you will be OK.....:wtf:

Don't forget to have the wires from each set of points going to the correct coil for the cylinder associated with each set of points! :doh:
 

Jan_P

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Not entirely sure of the English ...Off meaning not used or Off not at the right position
But it has to be right fex full retard at startup
That is something to work on and get right. It means the ignition coming out of sync with valves and pistons
 

Jim

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So I did confirm tonight that advance is off, will this alone cause similar issue?
Yes, not starting and pops out the exhaust are classic symptoms of being 180° out on timing. Just to confirm it, swap the plug leads and see if it'll start.
 

Duck749

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Thanks for help and info, moved advance to correct 180deg position, reset timing and one kick fired up and idled good again!
 
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