If I set idle to spec RPM's won't come down when shifting

[WiVR]

Worked on this again today. Adjusted the "adjuster" near the carb and up near the grip. Checked for vac leaks around all the boots. Inspected cable at carb end for fraying. Cable snaps back sharply on it's own when I release grip.

 

Same condition- rpms stay or float slowly down when I pull the clutch in when shifting.

 

The bike revs normally in neutral. No float-down issue.

 

Only way so far to solve the problem is to back out idle adjuster knob so idle drops to around 400 (then will run a bit and die). I have to keep the idle up at the grip when I stop, but otherwise the bike runs great.

 

Still stumped.

[Condor]

Worked on this again today. Adjusted the "adjuster" near the carb and up near the grip. Checked for vac leaks around all the boots. Inspected cable at carb end for fraying. Cable snaps back sharply on it's own when I release grip.

 

Same condition- rpms stay or float slowly down when I pull the clutch in when shifting.

 

The bike revs normally in neutral. No float-down issue.

 

Only way so far to solve the problem is to back out idle adjuster knob so idle drops to around 400 (then will run a bit and die). I have to keep the idle up at the grip when I stop, but otherwise the bike runs great.

 

Still stumped.

 

Just for the heck of it back off the R-L balance sync screw on the right side of the carbs about a half turn and see if that doesn't make a difference. #3 and #4 carbs may be adjusted too tight and when you adjust the idle screw on two you may actually be opening up the right side carbs??? If it doesn't help then screw it back in a half turn. Nothing 'Ventured'...[is that a pun??]... nothing gained...

[GeorgeS]

Well maby at this point, with everything haveing been done.

You just need to Re-Do the Sync proceedure, with a Morgan Carb Tune, or equivelant tool.

[Marcarl]

Some what my thoughts exactly, but here's where I would go with it, go whole, why piece meal it.

Back off idle screw so that #2 carb butterfly is seated, then turn in the idle screw so that it just,, repeat,, just starts to move the butterfly, now do the same for # 1 except you'll have to turn the sync screw instead, now do # 4 and then #3.

Now start the bike and turn in the idle screw so it will idle at 900 rpm. Adjust #1 carb so that it balances with #2 constantly turning the idle screw to maintain the 900 rpm. Once you have # 1 done, do the same to #3 but this time balanced to #4 only, not #2, and keep the rpm @ 900. Everytime to finish a balance blip the throttle so that you are sure things are seated right. Now you balance #4 back to #2 constantly adjusting to keep rpm at 900. Don't worry about doing this at 2000 or 3000, the carb balance means very little when the butterflys are open that much. If you have it right at 900, it'll be close enough at 2000, and if you adjust at 2000, you will screw up your 900 setting.

[WiVR]

New plugs and wires today.

 

Old plugs don't look bad at all. PO said they were changed about 500 miles ago. Wires looked original (22,000 miles).

 

Re-synched with Morgan Carb-Tune. Synched nicely at about 900RPM.

 

No change with original float down issue.

 

Before I synched, I tried the C screw 1/2 turn back out. Actually made situation a little worse.

 

Marcarl- can I do your procedure from "outside" the bike or do I need to open something up?

 

As it is I am riding at

 

Kevin

[jasonm.]

don't even try to have the idle too low. You'll have very low oil pressure on a hot day. That is why the idle is suppose to be 1000 +/- 50. I think you may have a stuck choke plunger. Maybe slightly open. Look carefully.

[frankd]

Jason,

 

Any chance you have the part number for the throttle cable that wears out?

 

 

Frank

[WiVR]

All the plungers appeared to work well. I lubed the shafts and #2 had a few bubbles around the nut at the base of the plunger but I tightened and they are gone.

 

I adjusted the idle back up to 900 and went for a spin. Same problem. In fact when I back off the throttle/pull clutch to shift, the RPM's increase a little. If I hold in the clutch they will hang and slowly float down.

 

This is only happening when I am in gear/moving. When I am in neutral, revs go up and down normally.

[Marcarl]

New plugs and wires today.

 

 

Marcarl- can I do your procedure from "outside" the bike or do I need to open something up?

 

 

Kevin

You will need to have access to the butterflys, so off comes the top of the air box, out comes the filter, and then remove the inner piece sitting inside the filter, it has 4 screws which need not drop into the carbs, for fear of loosing them to the utmost neathers. Now you can place a long screwdriver on the higher side of each butterfly, and gently put your hand on it as you adjust the needed screws below. A gently hold will be able to tell you when that butterfly starts or stops moving. Hope this helps.

[nomad]

All the plungers appeared to work well. I lubed the shafts and #2 had a few bubbles around the nut at the base of the plunger but I tightened and they are gone.

 

I adjusted the idle back up to 900 and went for a spin. Same problem. In fact when I back off the throttle/pull clutch to shift, the RPM's increase a little. If I hold in the clutch they will hang and slowly float down.

 

This is only happening when I am in gear/moving. When I am in neutral, revs go up and down normally.

 

My bike has the same problem, so I am curious that you have ever fixed the problem? I am very interesting in this issue.

Anyone has any suggestions, please do so.

 

Thanks much in advanced

Nick

[Jrichard]

I think a general rule of thumb is when you rev it and let go if the idle stays high for a short time it's to lean. When revved and it fails below idle for a short time it's to rich.

 

Without an analyzer it's like trying to sync Carbs by ear.

 

Mixture by ear, Turn the mixture screw in until loss of rpm then back out to the highest. Then back in until the idle doesn't change. Do all 4.

 

This setting should be what's called the lean best idle setting.

_________________----------stolen from Venturers.org:thumbsup2:----yrs ago------

[nomad]

I think this could be the new Dynojet kit that is recently installed. I don't know much about setting these jet, except turn them all the way in, and unscrew out for 3.1/2 turns.

Other than that there is no further instruction of how to tweek the main screw (jet).

Any further regarding this issue would be appreciated.

Nick