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Discussion Starter #21
i'd try 50 or 52 pilots and emr needle.
Mini update:

Received the goods. But, I can't test test out the carbs.

During a ride pre-rejetting the bike suddenly lost power to the motor, as if it was starved of fuel. All lights still worked. It is making the notorious clicking noise from the starter relay. I tried shorting the terminals on the starter relay but it would just barely crank for a second or two. I then used another battery that I am 100% certain it works (came from my M900 that I just rode) and no difference. Main grounds are good, fuses, and that's all I've really inspected so far.

So now I'll be chasing this electrical issue for God knows how long. I will try and have my roommate help me push start it. I assume if it cannot be push started then I'm probably in deep s*hit - starter and/or sprag clutch replacement? Ay, caramba.
 

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Does your oil sight glass suddenly have a gallon or two too much oil? Remove both spark plugs, put in gear and roll the rear tire forward - does gas shoot out the sparkplug holes?
 

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Discussion Starter #23 (Edited)
Does your oil sight glass suddenly have a gallon or two too much oil? Remove both spark plugs, put in gear and roll the rear tire forward - does gas shoot out the sparkplug holes?
Good idea. I checked for hydro-lock but nothing came out of the cylinders. Additionally, I just barely verified with a flashlight pointed in the spark plug hole that there wasn't any fluid or oil when the piston reached and went past the hole.

The oil level is where it was before this occurred.

Tonight I tried directly jumping the starter with the cables I have used thus far and the started winded for two seconds only twice. Now it won't even wind.

The cables are not old, and are a thick gauge with copper terminals. I would find it odd if they are shot.

My Shorai battery is fully charged.

Perplexing. I will try new cables tomorrow.

Regarding your idle issue:

I know as much as a rock as far as the FCRs are concerned, but I thought the idle speed screw only slightly opens the butterfly, effectively only leaning out the motor. Can someone verify this? When you mentioned idle was hanging after the motor had warmed up, do you mean to say that the idle speed was simply too high and thus you backed out the screw to decrease the idle speed, or, while keeping the idle speed screw at its location and while in idle and revving it would hang and return to correct idling RPM and that is what led you to decrease the speed? I think it's possible the implications from each scenario shed light on differing circumstances.

Based on Keihin's graph below the elements listed from idle to 1/8th are involved with the a/f ratio. Sorry if I missed it but I did not notice you mentioning fiddling with the slow air jet screw or the kind of needle you're running. EMT is stock IIRC.

By screwing out the slow air jet screw (pictured as the undone screw w/ a spring) 1 turn and revving the motor a bit to adjust to the 1 turn, the idle will usually suddenly jump. Thus my understanding is the more we turn that screw out, the leaner idle-to-1/8th throttle circuitry becomes. And the opposite is true. If it hangs, perhaps it's backed out too much, and must be turned in some. Even the slightest turn can have large effects. It might be worth fiddling with the slow air jet screw.

And of course the needle tip plays a role too. Per Brad's recommendation I purchased an EMR needle but as you know I cannot test the carbs and report back to you just yet since the bike won't even start. Since my bike is out of operation and I have my M900 still then perhaps it is a good idea I ship these EMR needles to you so you can fiddle around with them without committing to the purchase from Sudco. If they work out for you then you can pay for them then I'll purchase another set from Sudco.

My roommate is from Phoenix, Arizona. Two things he misses: end of summer, and open-carry laws.
 

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I have one 900SS with the stock Mikuni carbs, and a great deal of adjustments have been going on with it, but it doesn't have the hanging idle problem. The other 900SS with FCR41's does under the first hour of driving - again, not directly temperature related as I often start the bike "cold" when it is over 100 degrees F outside. Raise the FCR carb idle for about the first three stoplights, then drop it down to keep it from the hanging idle. If I ride for more than an hour I must raise the idle again or it will stall out. Once set back to where it was when "cold" I won't need to touch the adjustment again the rest of the day, no matter how many times I shut it off and restart it unless it sits for more than 6 hours.

How does changing a jet improve this procedure? Which jet? I am willing to listen to any argument explaining a possible sync issue causing this, I have eliminated any possibility of an air leak or imperfect seal on the intakes or filter. I bought the fancy Motion Pro II throttle setup, junked the Sudco provided Motion Pro crap, so it is not my cable routing or binding.

I think after 24k miles this is the nature of the FCR beasts,... prove me wrong and I will attempt to adjust them. It is a little annoying.
Just a question - but what do you have your idle mix screws set to?

Mine is at 3 turns out, and (I think) the air screw is around 1-1/2. At that, my bike starts with the usual 3 tries when cold (10-15C), idles without needing any extra idle speed wound on after a minute of 2500-3000 rpm running, and my idle speed doesn't change when it gets hot. It DOES smell rich when idling though...
 

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Discussion Starter #26 (Edited)
An update to below:

As promised, I whacked the starter like a mob member who's mother was disrespected. Starter now spins like an nitro RC motor, but only sometimes. I will replace the sprag clutch and starter motor considering I have 3 donor motors and the SS has 42k miles.

I can get back to the carb issue shortly. Will update one I drop in the 50 and 52 jets with the EMR needle.

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I'm going to ask a question I think I already know the answer to but I don't want the implications of what I am experiencing to be true and I am in slight disbelief.

I unplugged the ground cable from the starter. I then hooked up jumper cables to a working car battery (the car was always off during this experiment).

I then checked I had voltage in the other end of the cables. 12.56V, but who knows what the CCA is on those batteries. Anyway.

I attached the ground cable to the starter, and then I attached the positive to the ground cable nut on the motor that is behind the right-side rear-set.

Dude, nothing happened. But something is supposed to happen, amirite?

Does this mean the starter and/or sprag is stuck and/or damaged?

I will try to push start the bike in second gear and see what that does.
 

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By screwing out the slow air jet screw (pictured as the undone screw w/ a spring) 1 turn and revving the motor a bit to adjust to the 1 turn, the idle will usually suddenly jump. Thus my understanding is the more we turn that screw out, the leaner idle-to-1/8th throttle circuitry becomes. And the opposite is true. If it hangs, perhaps it's backed out too much, and must be turned in some. Even the slightest turn can have large effects. It might be worth fiddling with the slow air jet screw.
If screwing in the slow air jet screw, it feels mushy at the bottom (0 turn), the spring is too long and prevents proper seating of the screw.
Don't ask me how I know:(
 

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The biggest fix for me here when I was dialing mine in was the EMR needle. I am at sea level.

Second was upgrading to Ignitech and tweaking the advance curves in that rev range. Now it starts revs and idles very neatly from cold. I have some minor rev hang once warmed up that I plan to dial in with ignition curves when I get the time, but it is liveable as is.
 

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why did you connect the ground cable to the starter, and the battery positive to the engine cases? not sure if that should make it run backwards or not, but it's not right.
 

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Discussion Starter #30
why did you connect the ground cable to the starter, and the battery positive to the engine cases? not sure if that should make it run backwards or not, but it's not right.
Two owners prior did some unique electrical work. Now I'm stuck with a huge re-wiring job on the dashboard especially as he installed a MotoGadget speedo which required unwiring every single wire from the OEM instrument cluster.

I can verify that setup did work before on this bike, so I wonder if the starter is somehow immune to polarity and will always spin in one direction?

In any case, I'll update when I get this issue figured out. Carb jetting will resume once the motor fire up =)
 

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Discussion Starter #31
If screwing in the slow air jet screw, it feels mushy at the bottom (0 turn), the spring is too long and prevents proper seating of the screw.
Don't ask me how I know:(
Shouldn't the spring supplied have been the correct one? I purchased mine from Sudco and have not had this issue. It sounds like a PITA to chase a slow air jew screw issue without knowing that the particular unit was never properly seating. The little things in life...
 

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Shouldn't the spring supplied have been the correct one? I purchased mine from Sudco and have not had this issue. It sounds like a PITA to chase a slow air jew screw issue without knowing that the particular unit was never properly seating. The little things in life...
I bought mine, along with needles, jets, ect. from a reputable Sudco/Keihin dealer in Germany years ago.
Don't think it had something to do with the fact that, the carbs came off of a quartet meant for a Yamaha R1 - one part number for the spring/needle.
What I can tell you, it was a delight to tune them with the aid of a afr sensor/datalogger/tps sensor.:smile2:
Especially compared to Dell'Ortos or Mikunis.
 
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