Has anyone had this happen?

Silver Bullet

Supercharged
Joined
Sep 11, 2007
Messages
238
Location
Washington
Pushed the R3 outside the shop onto the tarmac this morning. It was about 45 degrees with bright sun shine and the wife and I decided to go for a little ride.
I fired the engine and went back into the shop to get my leather jacket. Upon my return (maybe a couple of minutes) I noticed the bike was running really rough..almost like it was missing. I revved up the engine a couple of times and noted the "check engine light came on" with no other warning lights. It does that sometimes and has since I've owned it.:confused:
We mounted up our rides, left the shop and went down the street. I noted that the bike was wanting to "sneeze" through the intake and was "laboring". I kept the bike running, but it was really running rough now at low RPM. I went two blocks and pulled over into a parking lot. My wife who was following on her Goldwing Trike asked what was wrong and said lots of black smoke was coming from the exhaust pipes.:mad:

I shut the engine down and thought about the symptoms for a couple of minutes deciding to cycle the key three times...(and old Ford Trick to reset the ECU)....and restarted the engine. As in the past the engine started, the light was off, the bike seemed to be running fine again. :)

We continued on our run and made numberous stops at stores without incident putting on about 25 miles in city traffic.

I have checked the ECM before when the engine light came on and found no codes. Has anyone else had this type of problem and if so, what did you do about it?

Merry Christmas All.....SB...
 
Never had it haen to the rocket but is sounds a lot like carburator ice to me. It takes about 35 degrees out of the air to turn gasoline to vapor and at 45 if it was very humid you get ice. Along with the symtoms ou discribe. It might be a ECM issue but next time check for frost. Allowing the bike to set for a moment lets things warm, volla ice is gone.:):)
 
I might be a moron, but carb icing issues @ 45F?

If it takes 35 degrees out of air to turn gas to vapor, is that to say that carbs could ice @ 67F?

If it happens again, I'd see if one cylinder feels cooler than the others by hovering your hand over the exhaust. Atleast that way you can determine which cylinder is giving you the issue. From there you can trouble shoot the cylinder.
 
I might be a moron, but carb icing issues @ 45F?

If it happens again, I'd see if one cylinder feels cooler than the others by hovering your hand over the exhaust. Atleast that way you can determine which cylinder is giving you the issue. From there you can trouble shoot the cylinder.
That's funny :roll:Which cylinder exactly is the lower right side exhaust. Remember there's a "log" to contend with; and, a cat box/exchanger involved in this mess.

I ride when temps dip well below 45F on a daily basis. No carb icing that I know of and the humility is often quite high in these here hills.

Fuel filter?? I don't know whether an ECU error would arise from a filter issue?? The stock fuel filter is in the tank :( If the issue is arising periodically I'd say you're mostly likely looking at a fuel supply issue. Electronics are either good or bad all the time, or at least consistent in their symptoms and a degraded plug wire would fall into that arena I believe.
 
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Goodfellow: Could be a plug wire, maybe a coil gone bad..does not explain why black smoke (very rich fuel condition) is coming out all three pipes though.

Pigger: When I cycled the ignition three times to reset the ECU, it apparently erases the codes. As stated, I have had the engine light come on before. It will eventually turn off on its own or can be "reset" by cycling the ignition three times. The "rough" running condition and "sneezing' or almost a backfire is a new symptom.

Gunshots: The weekend before we took a short ride at 33 degrees without issue. She ran great!

I am leaning toward an ECU issue. The symptoms, engine light, rough running condition, black smoke, may be signs of a failing ECU? HMMMMM. Does anyone think maybe a ground problem? I frankly don't know what to think on this one. My experience with ECU problems is that they either work or quit working entirely. This issue is intermittent. Any further thoughts???

Thanks for the input fella's. SB.
 
...I am leaning toward an ECU issue. The symptoms, engine light, rough running condition, black smoke, may be signs of a failing ECU? HMMMMM. Does anyone think maybe a ground problem? I frankly don't know what to think on this one. My experience with ECU problems is that they either work or quit working entirely. This issue is intermittent. Any further thoughts???

Thanks for the input fella's. SB.

Injector...still leaning to fuel issue. Crapped up filter letting crap through?? Try a fuel injector cleaner additive, perhaps twice. Then check filter You haven't filled up at a station receiving their own refill simultaneously?
 
Goodfellow: Could be a plug wire, maybe a coil gone bad..does not explain why black smoke (very rich fuel condition) is coming out all three pipes though...SB.

Only one cylinder needed to pollute the entire exhaust after the bottle neck.
A plug wire heating up to a failure point would be consistently failing at that failure point.
The same with a coil. Consistently...

A ground might an issue influence by ambient conditions.
 
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I might be a moron, but carb icing issues @ 45F?

If it takes 35 degrees out of air to turn gas to vapor, is that to say that carbs could ice @ 67F?

If it happens again, I'd see if one cylinder feels cooler than the others by hovering your hand over the exhaust. Atleast that way you can determine which cylinder is giving you the issue. From there you can trouble shoot the cylinder.

You can have carburetor/throttle body icing at any temperature up to around 50 degrees ambient. The vapor mixture has an extreme cooling ability as the airflow increases. Remember gasoline is a volatile easy to evaporate liquid. That mixed with ambient air and run through a throttle body or carburetor at increased velocities will cause frost on the aluminum castings within the venturi area. As the engine itself warms the throttle bodies or carburetors that condition ceases. My Bonnie has carburetor heaters that function at ambient temperatures below 50 degrees f.

If you have a compressor at home, on a hot day, crack the drain cock slightly to allow air to escape at pressure and observe the drain itself. You'll see frost build up around the opening. Same thing happens in a carb or TBI unit.
 
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