Topic: exhaust gaskets or header clamps

[evinrude7]

initially, after replacing the exhaust crush gaskets this winter i noticed deceleration popping was much less than before.  almost non-existent.  i've since put well over a hundred miles on the bike and the popping is back.  i tightened up the header clamps today.  they seemed to need it at this point after riding the bike a bunch.   i had them pretty tight back when reassembling everything.  when i installed the new crush gaskets i got the spigots pretty damned tight too.  should i pull the clamps and try to wrench the screws some more on the spigots?  or should i be chasing another issue, which could be slightly low float height. 

[flybox1]

if your exhaust pipe is not supported at the a$$ end, the bounding can make things sloppy at the header.  Do you have studs or bolts?
If you have studs, use lock washers or locking flange nuts to prevent loosening

Clear tube test #1 and 4 float bowls.  Let that be your guide.

[PeWe]

If your exhaust is leaking it will sound bad at idle and during throttling.
Deceleration popping seems to be more as too lean (or too rich) pilot circuit.
Stock CB750 carbs, right?
Pods or stock airbox?
Pods: Air screws 1/2 turn out, needles 1 step richer than stock. On my K6 was middle notch stock, 1 step down  from top richer.
Air box: Air screws 3/4 turn out, needles middle notch.

I have noticed that too advanced ignition will crave richer pilot circuit to function. This will make it to pop.

On both my bikes, K6 and K2 I had to tighten the adv springs to make it possible to make F to match case mark at around 1200 rpms which is a sound idle. Too advanced with the sloppy springs, maybe that's the way Honda stock springs are.
Advancer has a play when not tightened by the small nut, set it at max counterclockwise position and tighten it,

Now set the ignition. Important that the plate can not move sideways and up-down when its 3 bolts are not tightened. This will make ign setting to a never ending story. ( Point gap change when baseplate moves sideways)
If so , use a small and sharp tip of a hammer... lightly peening the crankcase bosses all around the plate to snug it up as described here:
https://www.motorcycleproject.com/text/sohcign.html
I did mine step by step until plate sits tight and possible to turn,

After that set ignition. http://www.hondachopper.com/garage/carb_info/timing/timing1.html
Points must be set by a dwell meter, huge difference. Cheap auto multi meters have that function.
8 cyl setting: set it to 23.5 degrees on each point, adjust while idling so ignition must be set so it runs. The range is 23-24.5 degrees. When both are equal, bike runs much smoother and you will see that the bad idling you might thought was bad synced carbs was ignition not properly set.

You will see that F can be set to case mark at 1200 rpm.
When springs are cut and reshaped its possible. Full advance at around 2600-2900 rpm and will happen more abrupt.

I did my K2 this weekend doing exact these steps. Making base plate to sit tight was done earlier.
http://forums.sohc4.net/index.php/topic,168243.msg2053657.html#msg2053657

Before this adjustment my bike (K2 build) bike must have air screws opened 1/2 turn, now 3/4 when ignition is not too advanced. It runs much better when revving it in the gsrage. My K6 needed more fuel screws causing stinking idle to not sneeze sonetines on 1 2 carbs at low lifts. Fixed by setting ignition correct, not too advanced at Idle. I noticed that on Dyno too, retard a little gave better result, 1-2 hp more. F at case mark when idling

If you must choose either stinking idle or popping idle, ignition is too advanced. That is how my bike have shown me the last years during adjustments that I finally could fully solve. I'm sure that this is why so many skipped points and used electronic ignition that is not dependent on a plate that can move sideways. Dyna 2000 has no spring advancer either.

[evinrude7]

if your exhaust pipe is not supported at the a$$ end, the bounding can make things sloppy at the header.  Do you have studs or bolts?
If you have studs, use lock washers or locking flange nuts to prevent loosening

Clear tube test #1 and 4 float bowls.  Let that be your guide.

Bolts. Made sure to have the mufflers supported and worked the headers into spigots until everything looked/felt right then clamps.

Sent from my LG-H871 using Tapatalk

[evinrude7]

If your exhaust is leaking it will sound bad at idle and during throttling.
Deceleration popping seems to be more as too lean (or too rich) pilot circuit.
Stock CB750 carbs, right?
Pods or stock airbox?
Pods: Air screws 1/2 turn out, needles 1 step richer than stock. On my K6 was middle notch stock, 1 step down  from top richer.
Air box: Air screws 3/4 turn out, needles middle notch.

I have noticed that too advanced ignition will crave richer pilot circuit to function. This will make it to pop.

On both my bikes, K6 and K2 I had to tighten the adv springs to make it possible to make F to match case mark at around 1200 rpms which is a sound idle. Too advanced with the sloppy springs, maybe that's the way Honda stock springs are.
Advancer has a play when not tightened by the small nut, set it at max counterclockwise position and tighten it,

Now set the ignition. Important that the plate can not move sideways and up-down when its 3 bolts are not tightened. This will make ign setting to a never ending story. ( Point gap change when baseplate moves sideways)
If so , use a small and sharp tip of a hammer... lightly peening the crankcase bosses all around the plate to snug it up as described here:
https://www.motorcycleproject.com/text/sohcign.html
I did mine step by step until plate sits tight and possible to turn,

After that set ignition. http://www.hondachopper.com/garage/carb_info/timing/timing1.html
Points must be set by a dwell meter, huge difference. Cheap auto multi meters have that function.
8 cyl setting: set it to 23.5 degrees on each point, adjust while idling so ignition must be set so it runs. The range is 23-24.5 degrees. When both are equal, bike runs much smoother and you will see that the bad idling you might thought was bad synced carbs was ignition not properly set.

You will see that F can be set to case mark at 1200 rpm.
When springs are cut and reshaped its possible. Full advance at around 2600-2900 rpm and will happen more abrupt.

I did my K2 this weekend doing exact these steps. Making base plate to sit tight was done earlier.
http://forums.sohc4.net/index.php/topic,168243.msg2053657.html#msg2053657

Before this adjustment my bike (K2 build) bike must have air screws opened 1/2 turn, now 3/4 when ignition is not too advanced. It runs much better when revving it in the gsrage. My K6 needed more fuel screws causing stinking idle to not sneeze sonetines on 1 2 carbs at low lifts. Fixed by setting ignition correct, not too advanced at Idle. I noticed that on Dyno too, retard a little gave better result, 1-2 hp more. F at case mark when idling

If you must choose either stinking idle or popping idle, ignition is too advanced. That is how my bike have shown me the last years during adjustments that I finally could fully solve. I'm sure that this is why so many skipped points and used electronic ignition that is not dependent on a plate that can move sideways. Dyna 2000 has no spring advancer either.

No popping at idle or while throttling. My timing was slightly retarded. I found out today after putting my timing light to it. It's right on F for both 1/4 and 2/3 after adjustment.  Done at 1200 rpm. Bike doesn't stink at all and while riding w a buddy who was on another bike following me he also said exhaust is not stinky. My guess is I'm a little lean. Still trying to find nylon barbs or grease fittings small enough to fit 4mm bowl screw hole.

Sent from my LG-H871 using Tapatalk

[evinrude7]

Clear tube test #1 and 4 float bowls.  Let that be your guide.

clear tubed 1 and 4.  both slightly low like a mm or 2.  got them to 4mm below.  i'll probably pull the rack to do 2 and 3.  haven't ridden it yet.