Backfiring, stalling, and throatier than usual | GTAMotorcycle.com

Backfiring, stalling, and throatier than usual

arogal

arogal

Well-known member
On my ride Tuesday night I noticed my 09 zx6r was performing quite strange once the bike reached operating temp. This was the first ride of the year the bike has reached operating temp 85+ because its been so chilly out so far this spring.
It sounded a lot throatier than usual. Best way to explain it is that it sounded very raw. It was also back firing alot on decel, and when I came to a stop it stalled on my twice. The rpm would drop below 1000 and instead of rising back up, shed die. Started but up just fine though. No lights flickering or dimming.
It was almost felt like it was bogging out in 3rd gear around 4000-6000 rpm on the throttle...almost like a misfire. The 2 stalls at idle got me a bit frustrated and I didn't really feel comfortable on the saddle, but when it cooled down a bit it was idling just fine.
Spark plugs and K&N filter put in immediately before my dyno tune last summer in August (about 3500km ago).
Strange thing is, it would run well, then poorly, then start popping again, then would run fine. Seemed to be the worst when I was sitting at a red light when the bike got warm and took off.
Valve clearance and throttle synch also done 700km ago. Only really recognized the issue this evening. It did sound louder after my valve clearance though, but in a good strong way.
Did load test on my battery last night. 12.8v with bike off, 14.8v with bike running. When I got back from the ride and turned bike off it read a full 13v so it looks like the charging system is working just fine.
Bike was running fine last night because it didn't reach operating temp because it was pretty chilly out.
I'm thinking it could be something as simple as a dirty sensor or a bad batch of gas. It seems to be air/fuel related as is only runs poorly when the bike has reached operating temp.
On the other hand it could possible be spark plugs (but just changed 3000km ago) or a coil pack?
Maybe some of you technical savvy people here could lead me into some sort of direction.
Thanks!
 
My first step was to look in the air box. Maybe some oil or other crap in there (dirty air inlet sensor possibly?). I have put 3 full tanks of gas in bike since winter. Just weird how it only happens once bike reaches operating temps. When bike temp is below 80 it seems to run just fine. But on the other hand, when the bike does reach operating temp that's when the sensors do kick in to regulate the air and fuel.
I'll also plug my laptop into the power commander to make sure it is getting power and that my dyno tune map is still on it.
 
You think bad gas would make a bike run that poorly? I hope its that easy of a fix, but with my luck it's not
 
arogal said:
You think bad gas would make a bike run that poorly? I hope its that easy of a fix, but with my luck it's not
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Yep. Haven't experienced it personally, but seen it on some YouTube videos. Very similar behaviour to what you're describing.
 
I'm willing to bet JavaFan's underwear that it's the gas.

There has been a lot of mice activity this winter. You might check the airbox as Wingboy says. My landscape lighting cables were eaten and a coworker reports that the mice made a nest under his motorcycle seat...
 
FLSTC said:
I'm willing to bet JavaFan's underwear that it's the gas.

There has been a lot of mice activity this winter. You might check the airbox as Wingboy says. My landscape lighting cables were eaten and a coworker reports that the mice made a nest under his motorcycle seat...
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I have a screen in front of my ram air filter and plug the M4 pipe with a big 'ol rag for winter storage so there shouldn't be any mice. I'll still take a peep in the airbox though. I had about 150ml too much oil in my bike last oil change (not enough to do any damage), but I may have some oil spray in the box.
Fingers crossed it's as easy as gas, because after doing research there are about 15 different things that could be causing the problem!
 
FLSTC said:
If you still need some help, I'll take your ZX6R out for an Italian tune up.
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Lloll! What's that? The shop? Because Ducatis are in the shop more than on the road!? ?
I'll only find out once it's warm enough for her to run at operating temp (usually 18c+). I'll keep ya guys posted!
 
Air filter was fine, no oil in the airbox either. Pulled the plugs and all of em were black. Turns out the bike is running rich and the person that tuned my bike it throwing it on the dyno to make some adjustments. Plugs were only in bike for 4000km.
Ran perfectly fine with the new plugs.
Once I get my bike on the dyno I'll show u results.
 
Update. Was riding around town last night and low and behold bike was running rough again. When I am in stop and go traffic it seems to run at it's worst as it stalled out on me as I was coming to a stop in 1st and pulled the clutch in. Started up fine. It popped 2 or 3 times easy on the throttle in 1st gear which means it is also misfiring, not just backfiring like a mf.
I am taking it to my tuner tomorrow and he is going to do a diagnostic on the dyno (be is almost certain it is a sensor issue as it only seems to be happening in certain conditions when the bike gets warm), but I am concerned that on my way there/way back it might bog out on me and leave me stranded as I will be riding from Burlington to Newmarket (110km hike). I don't have a hitch on my SUV or else I'd get a Uhaul trailer, and getting a tow is gonna burn a hole in my pocket for that distance.
What would you guys do, take the risk and ride there? It seems to run ok when I'm on the highway....it's when I am riding around town hitting lights when it is at operating temp/after it's been running for 15+ minutes.
In a bit of a pickle :unsure:
 
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old gas is done after the first few rides, this is something more.
I had some similar issue with my old cbr500 turned out to be electrical related, believe it or not, bad wiring.
 
bigpoppa said:
old gas is done after the first few rides, this is something more.
I had some similar issue with my old cbr500 turned out to be electrical related, believe it or not, bad wiring.
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There is a smell that's present....I thought it was chain wax as I started to smell is after I waxed my chain, but the smell still persists. It seems to be coming from my radiator area. It doesn't smell like burnt oil, it's more along the lines of what maxima chain wax smells like when you get some over spray on the exhaust. I start to smell it when I come to a stop, but the smells is not always present. It comes and goes.
Can you recall where your wires were toast on the cbr500? And what did you to to fix the issue? Whole new wiring harness, or did you just need to re-solder some connections?
 
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FWIW, I had the engine temp sensor go bad on my Softail. The bike wouldn’t idle or run well due to the incorrect temp input to the ECU/mixture. I had a CEL with code though. Was able to confirm the bad sensor with resistance measurements.
 
Do you run a lithium ion battery?
Probably be good to know what a lithium ion battery fire smells like, not sure I would.
 
Have you taken the fairings off and checked for any “mouse houses”? Also, look closely at the wiring to make sure it hasn’t been chewed through. Pay particular attention around the sensors.


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