She started! But she's angry!

[J_C]

OK... I do have the carb sticks so I'll give them a go when I return next week

[DimitriT]

Do a real vacuum sync. Bench sync is worthless in my experience. Had a completely cold pipe after a bench sync that cleared up totally after a vacuum sync.

Ditto. Bench sync is just to get it started so you can do a real vacuum sync. Also make sure you don't have any vacuum leaks. Did you put a plug over the vacuum nozzle on the #2 carb?

[J_C]

Ditto. Bench sync is just to get it started so you can do a real vacuum sync. Also make sure you don't have any vacuum leaks. Did you put a plug over the vacuum nozzle on the #2 carb?

What do you mean by putting a plug over the vacuum nozzle? That's connected to my petcock right?


Another question... I mentioned the best RPM method... is there a specific order to performing that (ie carb 3 then 4 then 1 etc). Also, should that be performed before or after the synch? I'm concerned about it in general since most people talk about their air screws only being out 1 or 2 turns, and when I started doing it for #4 it went 3.5 turns out!

[RotaryRodder]

have you checked to see if your cams are in time?

might not even be it but sounds a bit suspicous

[DimitriT]

What do you mean by putting a plug over the vacuum nozzle? That's connected to my petcock right?

This is something that gets me at least once whenever I start doing a sync. On the #2 carb body, there's a nozzle which you normally connect to a hose that goes to the petcock. You need to plug that up when you sync the carbs or all bets are off.

[J_C]

Ohhh I see. Yeah I'm able to elevate my tank enough to get access to the screws without removing the fuel and vacuum lines, so that should be just fine Thanks for the info!


Anyone else know if the best RPM method should be before or after the synch? I'll be working on that this weekend.

[chef1366]

If you know the procedure then you can do any cylinder in any order. Just after each one lower the idle so you can better guage the rpms rising.

[chef1366]

What jetting did you go with?

[J_C]

I'm still at the recommended settings by V&H (or was it dynojet?) but I'm strongly considering rejetting it again... I just need to prove the problem I have first

[terbang]

Errr. Edit above... I suspected that it would be due to a "richer" condition given the backfiring & flames coming from the pipe... but apparently the gold and blue are typical of a lean condition? Could anyone lend some advice?

Popping and banging and flames in the pipe especially on engine braking is caused by unburnt fuel being reignited during an exhaust stroke. These things spark every stroke because the timing is picked up from the crank. Unburnt fuel in the pipe usually means either there was too much (rich) or incorrectly ignited (poor ignition or timing or compression) fuel remaining after a normal cycle.