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Well, it's getting closer, but I still have some minor annoyances with my '78

So far, I've fixed an exhaust problem (minor one- the muffler fell off), set the timing at idle to 6 degrees BTDC, set and emery-boarded the points, rebuilt the carb, put on a new (to me) fuel pump and a new fuel filter upstream of the pump, put on a high-flow aircleaner cause it was running a bit rich and changed the plugs.

Here's what I got left, running problem wise:

-- Backfires on decel: just little pops and burbles when I am engine-braking, but it occasionally really goes off when I change gears.
-- Sluggish: It's okay around town, but on the highway it just feels wrong at speed- like it deploys a parachute at 60. It'll cruise at 65, but it sure feels like it's straining. Maybe that's normal, I dunno.
-- Stumbles off idle. When I hit the gas from idle, it tends to want to choke and almost stall. That's gotten way better since I put the muffler back on and rebuilt the carb, but it's still there.


As I mentioned, the timing at idle is set at 6 deg BTDC, the mixture screw is at 3 full turns, and the carb has a fresh rebuild. I checked a plug (#3 if it matters) and the ground strap was a *little* white, but the insulator was a really nice light to medium chocolate brown all the way down- I think I have the mixture very nearly nailed. Points are gapped at .017. Other than the few little problems I listed above, it's running like a top. All I need now is a body that doesn't have rust bubbles on the frame!

Merlyn

Any suggestions, or should I just get a "Heep honking, I'm reloading" bumper sticker to explain the occasional sharp reports, and drive her till she drops?

Hesitates at part throttle tip in? Straining at high speed? Both symtems of the vacuum advance not working. Have you checked this out? The 6 degrees timing is correct. A quick check of this= disconnect the hose from the vacuum advance and with the timing light on the mark, rev the engine a bit graduallyand the mark should move up the scale with the speed increase. Then reconnect the vacuum hose and do this again-- the mark should jump up the scale much farther and faster than before. This is an easy and quick check of the advance system.
Two things that cause backfiring are, a bad "dump" valve on the air pump, and the coasting richer solenoid not working on the carburator. I'm assuming you still have the stock Hitachi carb.