a log of my attempt to revive a motorcycle - for you to read & me to remember...

Feb 6, 2009

Post #9 - Engine: Everything I haven't Covered Before

There only a couple of systems I haven't talked about on the engine - fuel supply, ignition & exhaust - that's it, and these bits are short because I haven't had to do much & don't know much.

Fuel Supply
So I'm not really sure what kind of carb my dad was running on the Pan - it doesn't seem to look like any of the other common Harley carbs but it's clearly stamped with an AMF logo. I know it's newer & more sophisticated than the ol' brass Linkert card - it's got an accelerator pump & some plastic parts on it - I don't care really, I'm going to give this guy a try until I find it's limiting my performance or just junk.

The intake T is a stock, o-ring setup. A chrome coupler has been added to adapt this carb to the intake. The intake filter is also off a non-Linkert Harley - it's a stock round bit that I'm gonna rock until I can no longer rock it.

Ignition
My dad was running the stock points distributor, an Accel coil & wires and some champion plugs. I'm going to reuse the Accel coil & wires because those were fairly new and good quality. The spark plugs I'm not sold on yet - I have to do some research to see what heat range is preferred - when the plug is installed, seems the electrode is at least 1/4" from even being directly exposed to the combustion chamber. In my ideal world - the plug should have the electrode completely exposed & closest to the fuel source intake for best results - so I'll look around some more.

The old distributor was starting to get quite sloppy around the shaft & leaking on the longer rides - add to that fact that it's using points to contact circuits - a super vintage technology that's inefficient as compared to moder ignition systems - I sought to upgrade to a modern digital system. Through VTwin - I found this electronic, auto advance ignition that I assume was hosting some cheaper electrons for managing ignition timing & whatnot; but this assumption landed me a new points distributor with some auto advancing springs. This was definitely not the direction I wanted to go - not only does it not look original or cool - it now functions only marginally better than the original setup. I was looking for something with a rev limiter & programmable advance curve - but am not willing to shell out $500 for a Mallory distributor with dual fire - so I've settled to accept this new, moderately better ignition.

Exhaust
The pan made noise through a pair of un-baffled drag pipes, & the noise was good but the pipes did nothing for the pan's daily driver purposes except direct that noise out the backside. The pipes are too short to take advantage of significant inertial supercharging, there's no baffling to provide back pressure & then no cross-over tubes for flow scavenging - thus I intended to make my own system - a dual exhaust w/ pipes that ran straight back from the jugs w/ some baffles & cross-tubes. Seeing that the bike revival has consumed this much time already - I've ditched that idea for a stab at modifying the pan's current exhaust w/ some short baffles & header wrap. I'll someday build that new system & that day will be sweet.

That's it for the engine as of right now... until the rebuild!