Help a Rookie Learn

[Lazer]

Hey everyone. I'm trying to learn about my 1979 xs650 special that seems to have a lot of issues. The arms/fingers on the advance mechanism are worn so I'm replacing them. If I purchase Part #14-0652 will that give me everything I need or will I also need an advance rod? Anything else I'm missing?

 

[gggGary]

Yeah that should be all you need to repair the advance mechanism, your existing rod should be fine.

Auto Advance Unit Photo Auto Advance assembly mechanism. Complete advance as shown including cogged
mounting Nut. Fits: All XS650's 1970-84 (contact point ignition assemblies).
Replaces original units with worn or damaged parts.

OEM Reference #
• 256-81653-10

Part #14-0652 $65.00 USD Ea

Have you already disassembled it?

Have you considered upgrading to a pamco with e-advance?

 

[Lazer]

I haven't. The cost is what keeps me away from doing it. I'd like to get the bike running properly before I add what I think is a luxury. Thanks for the input.

Does anyone know about a slotted sleeve I need for this part?

 

[gggGary]

I understand and have done the same often. But..... By the time you are done nickel and diming the ignition; points, condensers, coils, wires you will have the cost of a Pamco and still have an old marginal points system.
Unasked advice? don't replace the advance yet, the timing range can be tightened by hammering the "bulbs" flat and carefully fitting to the slots, and adjusted by shortening springs if needed and bending the tangs on the backing plate in. I think it's retiredgentleman that has a how to on hammer/fitting the bulbs. This part from mikes is a reproduction not an OEM part, you may not be ahead on quality. AFAIK the slots on the plate do not wear significantly.

 

[retiredgentleman]

I haven't. The cost is what keeps me away from doing it. I'd like to get the bike running properly before I add what I think is a luxury. Thanks for the input.

Does anyone know about a slotted sleeve I need for this part?

The slotted disc is bolted to the advancer rod. The fly-weight "bulbs" fit into the slots of the slotted disc. The little "bulbs" wear smaller, and this increases the timing range, which can cause the full advance to go beyond the full advance mark (40 degrees). Going beyond the full advance mark can put a hole in the piston tops, which plays havoc with the compression ratio

When the "bulbs" wore down on my bike, I would peen or hammer them to make them larger to make a tighter fit in the slotted disc. That worked for a few years, but finally the "bulbs" started to crack, and I could see their days were numbered.

I was really happy when Pamcopete brought out the E-advancer for the standard Pamco ignition. The E-advancer is not a luxury. Its a great enhancement to the Pamco. No more fiddling/lubing with fly-weights and advancer rods. No worries about over advancing the timing. Engine runs smoother, as the timing advance is much more linear.

If you plan to keep your bike for many years, the Pamco and E-advancer is money well spent.

 

[650Skull]

There has been a report that the Mikes Auto advance arms have broken/pulled-out. May be a batch or just a bad one.

If you can afford it buy Pamco's e'advance