Help! my 1100 wants to be a 550 on occasion

[Mark Walsh]

Okay...Heres the rundown, Friday night, rebuild carbs...goes ok. Saturday morning, other half goes to Dutchess County Fair, she sees various livestock, I go on a 3 hour ride all over the place..."bike testing" as I call it. Sunday, go on a nice hour ride with a friend and his bike. He tries out my bike on a quick ride...comes back "somethings wrong" he says and I agree listening to it as he rolls to a stop. Its running on 2 cylinders...It sounds like. anyway, I vehemently deny that it was my carb rebuilding skills ( first time ) and start checking spark. Hmmmm...spark looks weak all around ( blue , NOT white and bright ) Plugs are <500mi, Just for kicks I reattatch all the plug wires and fire it up. VROOOMM. Starts right up?...Hmmmm..

Next day to/from work...no issues at all ( except that chilly morning air )

Today to work...highway, 70mph, repeat of the bike's electrically wanting to be a 550cc . Pull off highway and inspect wires.....pulled each while bike was running on 2(?) cyl. I get shocked ( weakly ) through the boots and wires ( around there ) no visible splits....reattatch plug wires....Fires up right and off I go to work....The ride home was with NO issues....what gives?? and has anyone else experienced same?

[GSexpress]

Okay...Heres the rundown, Friday night, rebuild carbs...goes ok. Saturday morning, other half goes to Dutchess County Fair, she sees various livestock, I go on a 3 hour ride all over the place..."bike testing" as I call it. Sunday, go on a nice hour ride with a friend and his bike. He tries out my bike on a quick ride...comes back "somethings wrong" he says and I agree listening to it as he rolls to a stop. Its running on 2 cylinders...It sounds like. anyway, I vehemently deny that it was my carb rebuilding skills ( first time ) and start checking spark. Hmmmm...spark looks weak all around ( blue , NOT white and bright ) Plugs are <500mi, Just for kicks I reattatch all the plug wires and fire it up. VROOOMM. Starts right up?...Hmmmm..

Next day to/from work...no issues at all ( except that chilly morning air )

Today to work...highway, 70mph, repeat of the bike's electrically wanting to be a 550cc . Pull off highway and inspect wires.....pulled each while bike was running on 2(?) cyl. I get shocked ( weakly ) through the boots and wires ( around there ) no visible splits....reattatch plug wires....Fires up right and off I go to work....The ride home was with NO issues....what gives?? and has anyone else experienced same?

1 & 4 fire off of 1 coil, 2 & 3 fire off of the other. If either of the pair of cylendars that are not firing are these, then it is most likely electical and coil related, as in the wire to the coil or the coil itself, not the spark plug wires. If it's another pair of cylendars that is misbehaving it's most likely the ingition box or the wires somewhere in the ignition system. If it is random or 1 & 2 0r 3 & 4 then it could be a lack of fuel getting to one side of the carbs or the other.

The first thing I would check are the connectors under the seat infront of the battery box that connect the magnetic pickup triggers to the ignition box. 4 bullit connectors I believe for your year model, but it could be a 4 pin plug. They will be inside a rubber boot. Clean em up with some small wire brushes, spray em with WD40 and that will probably take care of it. If not do the same for the wires and connectors to and from the coils. if it's still acting up you probably need a coil.

[almarconi]

Try running the engine when it is dark outside to see if there is arcing from the wire. You should be able to see it pretty easy. If you see arcing, use an insulated screwdriver to move the wire and see it the engine runs differently. The fact that you got shocked would lead me to believe the wires are at fault. When was the last time they were changed?

[Mark Walsh]

Try running the engine when it is dark outside to see if there is arcing from the wire. You should be able to see it pretty easy. If you see arcing, use an insulated screwdriver to move the wire and see it the engine runs differently. The fact that you got shocked would lead me to believe the wires are at fault. When was the last time they were changed?

No Idea....the PO was only a few weeks ago....is this a regular maintainence item?

[Mark Walsh]

1 & 4 fire off of 1 coil, 2 & 3 fire off of the other. If either of the pair of cylendars that are not firing are these, then it is most likely electical and coil related, as in the wire to the coil or the coil itself, not the spark plug wires. If it's another pair of cylendars that is misbehaving it's most likely the ingition box or the wires somewhere in the ignition system. If it is random or 1 & 2 0r 3 & 4 then it could be a lack of fuel getting to one side of the carbs or the other.

The first thing I would check are the connectors under the seat infront of the battery box that connect the magnetic pickup triggers to the ignition box. 4 bullit connectors I believe for your year model, but it could be a 4 pin plug. They will be inside a rubber boot. Clean em up with some small wire brushes, spray em with WD40 and that will probably take care of it. If not do the same for the wires and connectors to and from the coils. if it's still acting up you probably need a coil.

I'm almost positive its something electrical, as fuel issues "feel" different (if you know what I mean ) I'll clean up the various connectors as stated tomorrow after work...bikes gonna sit until tomorrow..Rain....also, these wire groups mentioned.....could that be intermittent?

[almarconi]

If the bike has the original plug wires from 1983 they should be replaced.

[rapidray]

DEFINITELY change the coils & wires as the STOCK coils are notoriously weak anyway. The plug wires & caps get old & have issues from deterioration & need replacing. Call Dynatek (626-963-1669) & ask for Larry-tell him Ray Rains sent you. Order at LEAST the 3.0 ohm coils & a set of wires. If you can swing it, get a Dyna S ignition also. Tell Larry I told you about him & see if he will give you a racer discount. Can't hurt to ask! Good luck & call me at 714-356-7845 if you need something answered in a hurry & don't want to wait on the Forum to answer. I have raced & built 16 valve 1100s since 1980 & am an ex-Suzuki dealer mechanic. Good luck, it's a fairly indestructible bike if done correctly. Ray.

[Steve]

... is this a regular maintainence item?

Unfortunately, yes, it is.

They should be replaced every 15-20 years.

.

[GSexpress]

I'm almost positive its something electrical, as fuel issues "feel" different (if you know what I mean ) I'll clean up the various connectors as stated tomorrow after work...bikes gonna sit until tomorrow..Rain....also, these wire groups mentioned.....could that be intermittent?

Yes, If there is corrosion in the conectors, heat, humidity and vibration can all affect the conductivity and therefore the voltage getting to the ignition box and or the coil. Being as it is 2 cylendars at a time that is cutting out it is a coil issue. it's not getting the full charge voltage, or the trigger voltage or it is grounded out or just plain burnt out. I doubt it's really bad as it runs good for a time. The connectors are a common problem in this scenario. Upgrading to new and better coils and wires is good but if your not getting full charge voltage or trigger voltage to them you may still have intermintent problems. If you replace every thing including the breaker plate then you will have unplugged and plugged these connectors anyway, never knowing if that was all you needed to do inthe first place. If you want to upgrade anyway it's a moot point. If you just want to get it running reliably the you might be spending a bunch of money unnessissarily.

[rapidray]

Trust me, replacing STOCK coils & wires & ignition plate on a 25 year old bike is NOT a waste of money! Take it for what it's worth to you! Ray.

[bonanzadave]

I replaced the plug wire caps with NGKs after a no start at a carwash. It did finally start after it dried out a bit. After the new caps - no problamo. I use to replace plugs, dist cap, rotor and wires on cars and trucks as routine maintenance but still have the 1982 coils and wires on the Bike.

Ray, How about Accel coils and wires ? Im guessing Kit 140403

Super Coil Kits for Universal Applications
These high output coils are intended for use on either 2 or 4 cylinder motorcycles.
Motorcycles that are point or electronically triggered, utilizing inductive discharge
type ignition systems would use 140403 or 140403S.
Motorcycles equipped with capacitive discharge ignition (CDI) will really come
alive when equipped ACCEL’s Super Coil for CDI applications 140404 or 140404S.
ACCEL’s engineers designed this coil’s special low resistance primary winding to
march operating characteristics of factory installed and aftermarket CDI systems,
getting maximum performance with fast rise times.
NOTE: Using the wrong coil may damage your motorcycle’s electronic ignition
module. To determine the ignition type, perform the following test:
1. Determine that the coil you are replacing is a twin tower coil.
(These coils will not replace signed tower coils).
2. Using a volt meter or 12 volt test light, hook positive lead to position post and
negative to ground on one of the stock coils.
3. Turn on ignition but DO NOT engage the starter button.
4. If there are 12 volts at the coil, the motorcycle has inductive type ignition. If there
is no voltage at the coil then the motorcycle has a capacitive discharge ignition
(CDI) because the power goes to the control box first.
Primary
Model Ignition Type Resistance P/N
2 Cyl (1 Coil Kit) Inductive (non Capacitive Discharge) 3.0 Ohms 140403S
4 Cyl (2 Coil Kit) Inductive (non Capacitive Discharge) 3.0 Ohms 140403
2 Cyl (1 Coil Kit) Capacitive Discharge Ignition 0.7 Ohms 140404S
4 Cyl (2 Coil Kit) Capacitive Discharge Ignition 0.7 Ohms 140404

[rapidray]

Those will work ok. I just use Dyna because they are close & they are friends. Ray.