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Losing power then shutting down

10K views 39 replies 9 participants last post by  rileyyh 
#1 ·
I've checked this issue in the forums, and found similar issues. But somethings I've noticed on mine, wasn't brought up. The other posts were about 4-5 years old, and didn't want to start replying to them. So I thought I'd start a fresh thread indicating what is happening with my bike.

Bike has been running pretty good since the beginning of the season. About a month ago, I did notice that the oil was down to about half way in the window. Okay, no biggie. Bike is still running fine, and I was scheduled to do an oil change soon anyway. On the way to work this past Monday, I felt my bike lose power for a second in second gear (didn't shutdown), but was ok after that. The rest of the ride was ok. On the way home, however, it did the same thing 3 times. 2 times happened while making a turn. Third time going straight shifting to third gear. Again, bike didn't shutdown. Just lost some power. This started concerning me. I made it home in one piece, with no stalling. That is, until I got to the garage in my building, my bike sputtered once, then shutdown. Tried starting it again, it was turning over, but no combustion. I started to smell something from the exhaust. Not the usual gas smell. More like oil, or possibly even electrical. Can't be too sure. Possible a mix of both. But definitely not the usual fuel smell that I've grown to like and accustomed to. lol I sat there for about 5 min, started it up again, and bam! Started. Managed to get it into my spot.

At first I thought I was probably running out of gas, so I checked the tank, I had half a tank left. Then I checked the oil window, didn't see any line. So I thought I was probably out of oil, or not enough. Causing my bike to lose compression and shutting down. So I topped it up. I let it run for a little bit, then rode around the garage (keep in mind I was limited to riding in first gear playing with the clutch), and no shutdown. Parked, checked the oil again, and still good level. The next morning, thinking all was fine, I started my bike, no problem. Got out of my garage, shifted to second gear, sputtered, then shutdown again. And like the evening before, it was turning over, but not combusting. Waited a few minutes again, and it started ok. Leaving the choke on seemed to help a bit. Luckily I wasn't very far from home, and was able to ride back gingerly. After I parked, I smelled that burning oil/electrical smell again. I checked the oil level again, and it looked fine. But I did notice some condensation at the top of the window where the oil level stopped. Not sure if that's an indication of any issues.

The most of the posters in the old threads said something like this is probably electrical. As in a loose battery connection, or faulty wiring. A few days before this started, I did remove my battery to refill and recharge it (I had forgotten to take my key out, and it was still in on position, drained the battery). So I'll check the battery connections to make sure nothing is loose. But other than that, could there be any other reason why my bike is doing this?

When I changed my plugs at the beginning of the season, I checked the coolant level, and all was good. Also changed my oil and filter. Bike ran fine for the next few months. Until this issue. I'm also wondering, if the plugs might have something to do with it? I gapped it within the specifications. But if I gapped it slightly off, in the long run, would it cause my issue? That's another thing that's been swimming around my head. Any input would be greatly appreciated.
 
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#2 ·
Next time it happens, open the gas cap and see if you get any venting noise like air suddenly rushing in. I can't speak to the electrical smell, but the rest of this really sounds like a fuel flow issue to me. On the 750 forums this is sometimes referred to as POOG (phantom out of gas).
 
#19 · (Edited)
I was reading for any threads about gas cap and pressure and saw this thread. I was test riding 15-20mph in my neighborhood in 2nd gear. On the way home, I tried throttling a bit more and I felt the power, but then it cut off and I noticed that the engine had died. It was difficult to restart and I was able to get it to idle weakly by throttling while starting. However, when i tried to throttle a bit, the idle weakened and died.

Once I parked the bike and turned off the bike and removed the key, I heard a high whine noise. I thought it was the fan but it wasn't. Then I noticed it came from the gas cap. When i opened the gas cap, it sounded like depressurizing. I could look in and see a clear tube with fuel in it and bubbles rising to the surface from the bottom of the fuel. The bike is difficult to start.

I checked the puke tube and it seems clear.

I took a video, don't know if it will help:

https://youtu.be/NN4zAZnH7JA

After reading this thread, I wonder if I have a loose battery connection (might have messed it up while putting the seat on. If it's normal for the gas cap to make that sound when the bike is turned off, then I would lean towards this, but I don't recall ever hearing that sound when turning off the bike.

It is a new (used) 500 tank for me. I am using the fuel cap from my previous tank (which I believe was a Vulcan 800 tank, looks identical but the petcock is further back for a V Twin config).

I'll go ahead and check part numbers to see if they are interchangeable. The meter was so I'm hoping it is.

UPDATE: When I closed the gas cap, it began making the sound within seconds even before I started the bike up. Once unlocked, it depressurized again.
 
#3 ·
Thanks fastpakr. I'll give this a go. A lot easier than an electrical issue. I'm really hoping it's as simple as a flow problem. Rather than a stator that's gone bad. Which is my worse case thought. That or a regulator issue.
 
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#4 ·
First you really need to determine if you are using or losing oil. The oil is not supposed to fill the window, but the oil level shouldn't change from one day to another (except due to bike tilt).
If you are burning oil it should be evident; if you are leaking oil, it should be evident.
Unignited fuel could cause a smell that is notable to you. Again, it could be electrical or fuel flow, but I'd bet its a loose connection and since you messed with the battery its the most suspect. Did you check and tighten both levels of battery connections - see sticky above. That one little loose connection can cause a myriad of symptoms from total shut down to hickups, to backfires, to smelly exhausts. The symptoms vary but the cure is often quite similar. Keep us informed. Tom
 
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#7 ·
That one little loose connection can cause a myriad of symptoms from total shut down to hickups, to backfires, to smelly exhausts.
That's so on the money. In hindsight, after I removed the battery last month to charge it, that's when I started noticing my bike backfiring more than usual, and that smell started happening. If my initial test ride is any indicator, the connection could very well have been the issue. I'll post back tomorrow on my full test ride.
 
#5 · (Edited)
I am having a similar issue with my 500. I just got it. If you find anything out Please let me know!!?
osplexis
Michael
osplexis@gmail.com

The guy I got it from said it was vapor lock but I don't think that is the case.
I did find a loose bat connection but that didn't cure my problem. I'll clean the connections and see how she fairs.
Thank You for any help you might be able to convey.
 
#6 · (Edited)
I think Peruano might be correct with this one. Before I even saw your post, when I got home, I decided to check the easiest things. Leaks, cracks, and loose connections. No leaks. I checked the connections to the battery, and they seemed ok. But I disconnected the battery and reseated it anyway. Test rode my bike, and same problem. I left it for a bit to grab dinner, and came back to it a couple of hours later.

Decided to check the battery again. And I don't know why I didn't notice this the first time around, or maybe it just didn't dawn on me at the time. I have extenders connected to the terminals on my battery, so that the wires can sit flat (it's natural position), rather than trying to bend it to connect sideways (terminals position). Anyway, these extenders were pretty loose. Loose enough that I can move them from side to side with one finger. So I tightened them up to the terminals, reconnected the battery and test drove my bike. I stayed within the side streets and close to home, just in case it conked out on me, I didn't have far to push it back. But I did manage to get to mid third (those darned speed bumps), without any issues. Which is better than before I tightened the terminal extenders. Didn't smell the burning either, or at least not as noticeable as before. It does make sense now, as the times I noticed it losing power (but not shutting down), I was hitting bumps on the road. As Peruano mentioned, lose connections to battery can cause power loss, on top of other things. And hitting those bumps could have jostled them lose, enough to cause the temporary power loss. If this was the problem (cross fingers), I'm surprised it didn't happen sooner.

I'm going to do a full test ride tomorrow. Taking my bike to work. Hopefully this was the issue and all is good now. I also didn't fill the oil to cover the whole window. Filled just below the top line. However, before topping up the oil (as part of my troubleshooting), it did drop from just above halfway in the window to an almost empty window within 7 months (oil change done back in March). I don't do a lot of highway riding. Mostly city, and a few times to the cottage (2.5 hours away) taking the scenic route this season. I could be slowly burning oil. No leaks. But that is another post.

I'll post back on results from tomorrow's ride.
 
#10 ·
That diagram in the sticky on check your battery connections is supposed to convey that there are two hidden (and two obvious) places for the battery connectors to be loose or need attention. So many of us overlook those lower ones, and need to be reminded to attend them. I'm glad it solved your problems. Tom
 
#12 ·
So the ride into work was "uneventful". Which in my case, is a good thing. lol Everything feels back to normal. Thanks again to all for your input.

Tom, I just read your sticky. And you were right on the money with my situation. Symptoms were exactly as you mentioned them in the sticky. I would never have thought about the battery connection of the L bracket. It is something that can easily be missed when troubleshooting.

Cheers.
 
#13 ·
Howdy guys
Battery connections aren't my problem. cleaned them up and dialectic greased them just ta make sure. And now it won't start at all, starter will turn over, but my start switch just clicks. I can smell fuel. I'm afraid I burnt up the starter solenoid trying to start it. Any idea what to check next??
 
#14 ·
IF it clicks when trying to start it, the battery is to low. Charge it.
How can you be smelling gas?
If you do have a gas smell, you have a leak somewhere.
Even a flooded engine wont have a gas smell.

First thing - make sure battery is charged.
Then check where the gas leak is.
 
#16 ·
It died while driving down the road. Then would fire right back up. but now won't start at all. I haven't pulled the plugs, guess i'll do that next. See if they spark but I'm pretty sure they are not. it dies like ya hit the kill switch. Previous owner put augzilary kill n start switch on it. I'm returning them to original. The "CLICK" ing noise comes from the fuse box. Not a fuse but I believe there is a relay in there as well. I've been looking for a wiring diagram, only found the 1500 so far.
I have fried the start solenoid (? maybe ?) . Got five posts below a 30 amp fuse, top right is hot with key on. ?
First time workin on a bike.

I am so very grateful for the feed back / assistance I have gotten thus far and appreciate any "HINTS" I can receive in the future.

Thank You All!
Michael
 
#17 ·
Michael, Your symptoms sound so much like some of those for the battery connection, I'd advise going back to the battery and checking everything. Grease does not make good connections, it just keeps them cleaner down the road. Check the battery voltage, but after that go for the connections (do them all or at least make sure you did not miss one or break off the terminal). Tom
 
#18 ·
Thank You Tom,
Yes. I went back to the battery. Took sandpaper to the connections ta make sure there was no oxidation, both the wires connections and the battery. Tested for voltage at the other end of the wires and it's all good. I would like to know what the solenoids transfer power to so I may check ta see if it is actually getting there. And is there one in the fuse panel?

Michael
 
#21 ·
Interesting...maybe I never heard it cause I had the other non-500 tank on the bike.

Any guidance on why the motorcycle might have shut off under throttle? I'm guessing too much fuel at 3 turns out on both carbs (although I think the fuel/air mix screws only affect idle).

I'm planning on looking at the trouble shooting guide in Haynes manual as well.
 
#22 ·
Tried draining carbs and they have fuel. Checked battery connections and all four points are secure. Checked air filter and it is wet and smells like gasoline. I'm rinsing it in water kn filter, but does this mean I need to make the screws more lean? They are currently 3 turns out on both sides.
 
#23 ·
I changed out my KN filter and put the old filter back in. The puke tube looked clear and lighter than the dark liquid before, so I assumed it was empty. I started the bike with full choke and it felt like a weak idle. I then adjusted the pilot screws and turned them in and felt the idle pick up. I went to half choke and it weakened but then picked up. I continued closing the pilot screws in, trying to get the highest idle. It still wasn't idling as high as it had been right after carb cleaning, but it was idling at a normal rate. I closed the choke and continued adjusting and it sounded ok. I throttled and it immediately felt weak. I thought the right side might be too lean so I opened up a bit and it seemed better, but opening up more didn't seem to increase rpms. I throttled and it still seemed weak. I turned it off to take a break and then saw liquid (I'm thinking gasoline) was pouring out from the side of the air filter onto the floor. I thought, maybe the puke tube is full and I quickly tried draining it and yes, out came a liquid, slightly darker and thicker than gasoline, perhaps a quarter cup.

So my issue seems to be that gasoline is overflowing into the puke tube and going into the air filter as well.

1. any tips on cleaning the original air filter? i ordered a cleaning kit for the KN filter.
2. does pilot screws have anything to do with the gasoline going to the puke tube?
3. does the weaker idle indicate that the spark plugs might be wet with gasoline and gasoline might have overflowed into the crank case or elsewhere?
4. how do i remedy the overflowing gasoline?
 
#24 · (Edited)
In addition to the questions above, here is an update. I checked the number of times the pilot screw was turned while the bike was off and I had actually closed the right pilot screw all the way, and it had still been running fine. I'm suspecting a possible stuck float issue in the right carb. I read that fuel flowing into the air filter might mean a stuck float. I had replaced the float needle and pilot screw assembly in the left carb, but had left the right alone. Appearance wise they looked fine.

One thing that also leads me to thinking perhaps its a stuck float in the right carb is that, while the screw was adjusted where the bike seemed to idle poorly, I noticed dripping from the puke tube. I tried tilting the bike upright from the side stand and all of a sudden the dripping became a flowing of fluid (probably 95% gasoline) from the puke tube.

I've currently got the screws adjusted where the rpm sounds the highest and most regular during idle. However, I'm still having a bogging down issue when I rev the throttle in neutral.

It's just a guess but I'm thinking:
1. inspect carbs and replace float needle and pilot screw assembly in the right carb
2. check and clean spark plugs
3. smell crank case for gasoline
4. oil change
5. clean kn air filter and install

Let me know if I'm on the right track or if there is something obvious that I am missing.

Oh, and I noticed I can't start the bike unless I have throttle fully open, which I believe means engine could be flooded? It also seems to have difficulty running with choke and better with none.
 
#25 ·
riley,

I did not view your video before responding before and agree that the noise is rather excessive for the 'singing' part. The noise is kind of a pressure release valve in the tank vent system. When the tank has excess pressure a valve opens and allows the pressure to dissipate in the air. Your bike is sitting in the sun, exacerbating the issue. The clear tube with bubbles inside the tank has be baffled. Does your bike have the 'charcoal canister' installed in front of the swingarm? How many hoses are connected on the right side of the tank?

I am guessing that the tank has excess pressure in it causing the carburetor(s) to flood. This will cause the running issues you describe.

Regarding adjusting of the idle mix screws, *always* make adjustment with the engine at operating temperature and the choke fully closed. Any adjustment outside these parameters does not help. It is entirely possible to have each idle mix screw at a different settings. (ex.: Hidalgo has one side at 2 1/2 turns and the other at 3 1/2 turns) The idle mix screws will have no effect on fuel getting into the airbox. You may have mentioned it elsewhere but have you had the carbs off/cleaned?

Have the carbs been synchronized/balanced? If not do it (or have it done). Balanced carbs perform better.

Regarding bogging on acceleration: Is the air filter still in place? Without the air filter it gets too much air and does not run right. A K&N OEM replacement filter is good. Hidalgo has one.

If you are concerned about fuel getting into the crankcase do an oil change now. It's cheap insurance.

Spark plugs: I have had better luck with NGK DR8EA spark plugs.
 
#28 ·
The clear tube with bubbles inside the tank has be baffled. Does your bike have the 'charcoal canister' installed in front of the swingarm? How many hoses are connected on the right side of the tank?

I am guessing that the tank has excess pressure in it causing the carburetor(s) to flood. This will cause the running issues you describe.
The old fuel tank I had did not appear to have the clear tube visible inside the fuel tank. So it's not something standard with the EN500C tanks? This is from a 2009 model.

Do my issues go with this thread or should I begin a new thread, outlining all the recent activity and maintenance done and the issues that developed?
 
#26 ·
Sounds like you have a float or float valve issue, I'd tear the carbs down, clean valve and valve seat, check float height, and make sure they are sealing.

If there is any tiny thing blocking that valve it will just let fuel run and run. I very recently had this problem. I took it apart and cleaned it, it looked and felt like I did nothing, but there was something in there preventing the valve from closing and everything was good to go next startup. It was very obvious that I had an issue because the carb would overflow if I filled it on a bench. I cleaned it until it no longer did that and played with the float height a bit.
 
#27 ·
I think there may be a black cylinder below the carbs, not 100%. I have two hoses on the right. I believe they are correctly hooked up but not sure. One is open ended and hanging below for maintenance. I'll have to check later when it's brighter.

When I got the tank, it looked like the front right nozzle had a piece of hose that appeared to be cut. It was the hardest hose to remove.
 
#29 ·
I did not view your video before responding before and agree that the noise is rather excessive for the 'singing' part. The noise is kind of a pressure release valve in the tank vent system. When the tank has excess pressure a valve opens and allows the pressure to dissipate in the air. Your bike is sitting in the sun, exacerbating the issue. The clear tube with bubbles inside the tank has be baffled. Does your bike have the 'charcoal canister' installed in front of the swingarm? How many hoses are connected on the right side of the tank?

I took a closer took and I don't believe I have a "charcoal canister" in front of the swingarm. The fuel tank does indeed have two hose connections on the right. I believe the front is left open near the right exhaust and the rear hose goes elsewhere, somewhere towards the middle.

I saw that both hose connections on the right had pipes or tubes inside. I think the front connection had a metal tube and the rear connection had the clear tube with liquid.

I found instructions on how to clean the tank cap using penetrating oil, so I went ahead and did that today.

I removed the oem air filter and of course it smelled like gasoline since fuel had poured out from there.

I opened the engine oil hole and it smelled strongly of gasoline, so I won't run the bike again until I do an oil change.

Does this mean spark plugs are likely going to need cleaning?

I am guessing that the tank has excess pressure in it causing the carburetor(s) to flood. This will cause the running issues you describe.

Regarding adjusting of the idle mix screws, *always* make adjustment with the engine at operating temperature and the choke fully closed. Any adjustment outside these parameters does not help. It is entirely possible to have each idle mix screw at a different settings. (ex.: Hidalgo has one side at 2 1/2 turns and the other at 3 1/2 turns) The idle mix screws will have no effect on fuel getting into the airbox. You may have mentioned it elsewhere but have you had the carbs off/cleaned?

Have the carbs been synchronized/balanced? If not do it (or have it done). Balanced carbs perform better.

Carbs haven't been synchronized/balanced. So far, I've adjusted it while idling warm to where the rpm seems highest. But it had difficulty starting even with throttle open, but that's the only way to start it. Is a cheap vacuum gauge easier to use than making a cheap manometer? I don't mind spending $20 more if it works better or easier.

Regarding bogging on acceleration: Is the air filter still in place? Without the air filter it gets too much air and does not run right. A K&N OEM replacement filter is good. Hidalgo has one.

Filter was always in place. I think both filters got fuel on them so it may have limited air flow.

The only incident that happened before all these new issues was that the bike ran out of fuel while idling well. I didn't realize so I tried starting again, which it did then shut off. The petcock was on reserve at the time. I wonder if air got into the fuel line or somewhere in the fuel tank.
 
#30 ·
I think I got this figured.

Whistling Gas Cap - resolved by cleaning out with penetrating oil (no more sound, even after sitting out in the sun). No pressure release sound when opening fuel cap after running.

Starting and Idling Issue - resolved by cleaning and re-oiling my KN air filter. oil change resulted in black oil coming out (I went with BikerBill Fram and Pennzoil 10W-40 this time)

I was able to ride around and was accelerating when, once again, the engine shut off somewhere passing 30-35 mph. Being able to duplicate this issue while having resolved the other issues makes me think that the jet that controls the speed starting at 30-35 mph is clogged (perhaps some new debris got into the recently cleaned carb, although I realized afterwards that I forgot to force air through the jets).

Tomorrow's task will be re-check the carbs and clean the jets and force air through everything until I can see the air flow through, then reinstall. I'm hoping this will result in being able to ride beyond 30-35 mph, all the way to top speed. Let me know if there is anything else that would cut the engine off during acceleration.

------------

1. After the bike stalled out, it wouldn't want to start unless WOT. I attributed this to a flooded engine and read online that time evaporating the gas was necessary to restart it. A few hours later, I tried restarting and it did restart, although it didn't idle as strong as it should. I'm hoping that more time will get it back to normal, but if you have any tips on starting after flooding an engine, please let me know.

2. Do you know which jet (or part) controls the speeds beyond 30 mph?

3. I had ordered one carb rebuild kit and replaced the pilot screw assembly on the left carb. I can feel the spring feeling creaky on the right carb. Is there a way to know when the pilot screw needs to be replaced? I just saw some dirt buildup on the pilot needle where it poked out of the carb body.
 
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