Topic: Won't start after changing spark advancer

[SOHC4ever]

Bike is a 76 750F. Engine out of a 73K, though.

I had this thing running pretty good all weekend. The plugs were kinda dark, and I was planning on doing a plug chop shortly after replacing the spark advance, which was failing as indicated by the "F" and advance marks jumping around during dynamic timing procedure.

I got a "new" spark advance unit from bikeboneyard and bolted it in just like the old one came out, and I can't get the bike to start for the life of me. I cranked it and cranked it, checked for spark on all 4 plugs (present. weak on #2, though), put them back in, wired it back up and cranked away again. Getting gas for sure, too. It backfired through the airbox a couple of times, then let out the mother of all backfires through the tailpipe. BANG!
Every bird in earshot took off like it was hunting season and every dog in my apartment building and the neighboring apartment buildings, and the park across the street started yapping its fool head off.

After the first few exasperated, scolding looks from the balconies on my tower I decided to pack it in and see what the forums think.

So, what do you guys think? Should I move to a different apartment building?
Also, what did I mess up while I was replacing my spark advance?

[joeb]

180 degrees out check your wires sounds like they are hooked up wrong.  I may be wrong but someone will correct me if I am, point cam may be 180 out

[bwaller]

+1 joeb

[bistromath]

hey i've got 10 bucks that the points cam is installed 180 out, not the wires. take off the points plate, take out the spark advancer, turn that cam around. i've done the same thing.

[joeb]

Thinkin the same thing just threw in the wires as a recheck on  the work done never know the things you can do wrong and not notice unless rechecked.

[SOHC4ever]

K.

Wires are right.

The points cam, I assume, is the part that the SA sits flush with on the back side? The advance only goes in 1 way.

I've attached a pic of what I'm talking about .

Thanks again for everyone's help.

[bistromath]

You're holding the points cam in your hand in that pic. Remove it from the advance assembly, rotate 180 degrees, and put it back on. Then ride.

[bistromath]

To be clear, it's the thing you're holding ONTO in the pic. It slides off the advance assembly when you line up the "keys" of the advancer tabs. Hard to explain, easy to do.

[SOHC4ever]

To be clear, it's the thing you're holding ONTO in the pic. It slides off the advance assembly when you line up the "keys" of the advancer tabs. Hard to explain, easy to do.

VAARROOOOOOMMMM!

Thanks, SOHC Forums!