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Discussion Starter #1
Hi, I'm a new member. I have a 1994 900ss with 5700 miles. Has been sitting for 22 years. I have gone through the carbs 3 times. checked coils, which seem to be ok.

when I spray carb cleaner into the rear cylinder carb is slows and may stall the engine. When I spray carb cleaner into the front cylinder carb I get almost no response. It might slow a little, maybe.

My sparks on my Ducati seem wimpy to me. My Harley Davidson spark is strong like a lighting bolt. It snaps and sparks crisp. My Ducati looks like a little girl is dancing ballet. the spark jumps around the ground strap. It sparks in the front, then the side, then the back etc.
No crisp sharp snap. No lighting bolt snap.

Any suggestions fellow Duckateers.
 

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Hi, I'm a new member. I have a 1994 900ss with 5700 miles. Has been sitting for 22 years. I have gone through the carbs 3 times. checked coils, which seem to be ok.
When you state you have gone through the carbs 3 times, have you pulled the jets and cleaned them with an ultrasonic cleaner or just sprayed carb cleaner in them? Does it idle at all? What about on throttle?

Coils seem okay? How did you check the coils? DVOM or just visually?
when I spray carb cleaner into the rear cylinder carb is slows and may stall the engine. When I spray carb cleaner into the front cylinder carb I get almost no response. It might slow a little, maybe.
I'd say that means the horizontal cylinder is where the problem is then. Likely in the carb. Does it run better with partial application of the throttle? Or does that make it worse? How does it run with the choke on, better or worse?

My sparks on my Ducati seem wimpy to me. My Harley Davidson spark is strong like a lighting bolt. It snaps and sparks crisp. My Ducati looks like a little girl is dancing ballet. the spark jumps around the ground strap. It sparks in the front, then the side, then the back etc.
No crisp sharp snap. No lighting bolt snap.

Any suggestions fellow Duckateers.
Sounds like it could be a poor ground. Also could be the connection at the coil signal wire, or the signal itself. Wiring insulation could have deteriorated after 22 years, what condition are the plug wires in? Are the leads clean inside the caps? How old are the plugs?

Sorry, I just have more questions than answers for you. I don't have a reference to make any kind of reliable input. How old is your Harley? Newer bikes, Harley included use much more efficient ignition systems. If you are talking about the difference in spark between a 2010 on up versus a 1994, with an ignition specified in 1992.....there's a huge difference in how fat that spark is gonna be.....sean
 
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Two grounds, the battery strap and another down by the brake pedal. Clean both thoroughly. New plug wires and caps and plugs, one of those needs to be resistor type. The carb that doesn’t change probably has a plugged pilot circuit. Since it will run, try removing the mixture screws and spraying the passages with carb spray. Adjust to about 4 1/2 turns out to start. Run some good carb cleaner through the tank, like SeaFoam or such. Several companies make a wiring upgrade kit with better wiring to the starter which can help a lot.
 

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When I bought mine 1997 900ss the first thing I did was changing the spark plugs, the leads and the spark plug caps. I had a weak spark and the bike did not run very well. It didn't stall but lacked power at low revs and backfired once and a while.
I made sure that the spark plug leads didn't make any contact with the wires that connect the pick-ups to the Kokusans.

Then I bought some 25 square millimeter battery cables (red for battery->solenoid and solenoid->starter, black for battery->frame, frame->engine).
A guy from the technical department at work attached some Klauke lugs and covered all the exposed copper parts with glue-lined shrink tube.
You can buy plug and play sets from ExactStart, Motolectric but they will charge you around 100$. I payed 15€ for the cables and the rest I got for free (I like nice co-workers).


The result were bright sparks and a much better running and starting engine.
Maybe this might help to solve your problems!
Good luck!
 

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Discussion Starter #5
I have dissassembled and cleaned everything, jets, all holes and passages, all new rubber parts including diaphragm.

It does idle. I just can't get the air screws to respond very well. When it gets hot it has that lean condition of the idle hanging high and slowly dropping.

It throttles up fine.

Checked coils with volt ohm meter.

It runs with partial throttle. Worse with choke.

The plug caps are clean, but old. I have just ordered new ones from Ca Cycle works.

I will check all the wiring and nd grounds.

The harley is a 2005.

Thanks for your time and input.


Steve1994
 

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Discussion Starter #6
I will check those items.

Thank you for your input and time.
 

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I have dissassembled and cleaned everything, jets, all holes and passages, all new rubber parts including diaphragm.

It does idle. I just can't get the air screws to respond very well. When it gets hot it has that lean condition of the idle hanging high and slowly dropping.

It throttles up fine.

Checked coils with volt ohm meter.

It runs with partial throttle. Worse with choke.

The plug caps are clean, but old. I have just ordered new ones from Ca Cycle works.

I will check all the wiring and nd grounds.

The harley is a 2005.

Thanks for your time and input.


Steve1994
I'm no expert by any means but that sounds like you have more than a single issue.

I think maybe you have a vacuum leak. That could result in a poor idle as well as it running better under part throttle and throttle up being mostly normal.

The hanging high idle with the slow drop is something else. I'm just not certain what. Throttle or choke cable binding possibly? Are they both well lubricated? Throttle shaft possibly?

When you say you disassembled everything, did you split the carbs? If so, that might be the source of the hanging idle issue. Maybe. Keep us updated of what you find........sean
 

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Discussion Starter #9
I just reassembled the carbs. I did find that the choke seal I had installed incorrectly. That may have held the choke open a slight bid which would screw up everything. I am waiting for a new air jet before I can test again.

Thanks
 

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Discussion Starter #10
I have had them all over the place. 2turns, 3 thrns 5 turns etc
 
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