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Discussion Starter #1
2011 Honda CBR250r
11,000 miles

Died on the freeway the other day, It was very difficult and unsafe to manuever from left lane to the side of the rode.

Electricals still working, starter seems to be turning motor fine.

Checked spark plug and it fires fine but I replaced it anyhow, still nothing. Spark plug seems to be getting plenty of fuel on it.

So what gives? How else can I troubleshoot?

I bought this bike used and have put less than 100 miles on it so the fact that it isn't running with only 11k total on it is really pissing me off. I figured a Honda 250 would be very low maintenance, guess not.

Any expertise would be greatly appreciated, I want to avoid paying the dealer to fix this if possible.
 

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Im not a pro or anything, But this is what it sounds to me.

If you bought it used with 11k and only but 100 on it and its having issues, it is most likely something the owner knew that was wrong with it and sold it.


But, The way it sounds to me is like bad gas or something. I would drain the tank, Check the battery voltage, check the air cleaner and see if that solves anything. These new eco bikes can be very picky when it comes to using old gas. They may of had the bike sit all winter and not change the gas, so that is what im thinking.

Wish the best of luck with you getting it running though.
 

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Im not a pro or anything, But this is what it sounds to me.

If you bought it used with 11k and only but 100 on it and its having issues, it is most likely something the owner knew that was wrong with it and sold it.


But, The way it sounds to me is like bad gas or something. I would drain the tank, Check the battery voltage, check the air cleaner and see if that solves anything. These new eco bikes can be very picky when it comes to using old gas. They may of had the bike sit all winter and not change the gas, so that is what im thinking.

Wish the best of luck with you getting it running though.

The owner was not technical whatsoever and It ran fine at first so I doubt he intentionally sold me a lemon.

I've put around 80 miles on the bike and have run through a complete tank of fuel so I really dont think its the gasoline but I will try that if I can't find a more likely cause....

If I can find an explanation for why the bike suddenly died it might help. I was doing 70 mph and it just kind of sputtered out. I just got into the reserve tank at the time and have added more fuel since. Is there a fuel tap on this model that I should be considering?
 

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Fuel that has gone bad is always a possibility when it comes to a bike that is hard to start, but the fact that you were able to ride it for nearly 100 miles kind of eliminates that as a likely cause... unless you had just refueled the bike, and had gotten some badly contaminated fuel.

Reviewing what you've checked so far:
- You have good spark at the spark plug
- Spark plug is getting fuel
- The starter turns the motor over

I'd say the next thing to do is a compression test.

An engine which has spark, fuel, and compression should be able to be started.
-
 

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The owner was not technical whatsoever and It ran fine at first so I doubt he intentionally sold me a lemon.

I've put around 80 miles on the bike and have run through a complete tank of fuel so I really dont think its the gasoline but I will try that if I can't find a more likely cause....

If I can find an explanation for why the bike suddenly died it might help. I was doing 70 mph and it just kind of sputtered out. I just got into the reserve tank at the time and have added more fuel since. Is there a fuel tap on this model that I should be considering?
The bike is fuel injected, so there is no "old school" on/off/reserve fuel switch. Do you think that you could have just run it out of fuel? What was the fuel gauge showing when it died?
 

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Discussion Starter #7
The bike is fuel injected, so there is no "old school" on/off/reserve fuel switch. Do you think that you could have just run it out of fuel? What was the fuel gauge showing when it died?
The fuel gauge had just flashed that it was on E, but Ive read the reserve tank on these models is almost half the overall capacity so it shouldn't have been close to truly empty. And like I said Ive added more fuel since I've been trying to restart it. Its at 3/4 a tank, since I've added more fuel I've had to recharge the battery twice with as much as Ive been turning it over. The spark plug also comes out quite wet, so lack of fuel in the cylinder should not be an issue.

How does one go about testing for compression? Before I took the spark plug out the first time it was very loose, like only a few threads were holding it in. I'm not sure if that indicates anything...
 

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Every engine requires four basic ingredients to start: sufficient cranking speed, good compression, adequate ignition voltage (with correct timing) and fuel (a relatively rich air/fuel mixture initially).

It could be your kill switch could be on, make sure its in neutral, spark plugs could be wet, kick stand up then try and start

Im not a expert just a few things a squid like me tries.

Sorry I can't help anymore then that :/
 

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You checked the spark plug and it fires fine, but where does it fire fine, on the bike or
did you test it elsewhere? My hunch is you lost power to the ignition system, because if you have spark and fuel you should have action unless they are completely out of sync.
You need to read the codes from the ECM (see the service manual or get help)
Good Luck, and keep us posted.
IR
 

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The fuel gauge had just flashed that it was on E, but Ive read the reserve tank on these models is almost half the overall capacity so it shouldn't have been close to truly empty. And like I said Ive added more fuel since I've been trying to restart it. Its at 3/4 a tank, since I've added more fuel I've had to recharge the battery twice with as much as Ive been turning it over. The spark plug also comes out quite wet, so lack of fuel in the cylinder should not be an issue.

How does one go about testing for compression? Before I took the spark plug out the first time it was very loose, like only a few threads were holding it in. I'm not sure if that indicates anything...
That you found the spark plug was loose in the cylinder head is a definite problem. I'm still thinking that having a compression test performed is the next step in diagnosing the problem. To do this test requires a compression test gauge, along with an adaptor to fit the spark plug hole in the cylinder head. I'd say at this point your best bet is to get the bike into a Honda dealer and have them check it out. If you do take it in, definitely tell them about the loose spark plug.
 

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That you found the spark plug was loose in the cylinder head is a definite problem. I'm still thinking that having a compression test performed is the next step in diagnosing the problem. To do this test requires a compression test gauge, along with an adaptor to fit the spark plug hole in the cylinder head. I'd say at this point your best bet is to get the bike into a Honda dealer and have them check it out. If you do take it in, definitely tell them about the loose spark plug.
:( I was afraid I was coming to the end of my troubleshooting abilities in my garage, I think I will have to take it into the dealer.

I guess the fact that it died on the freeway and the sparkplug/fuel was not the cause throws up some major red flags. Hopefully I don't need an entire new motor, but its just hard for me to believe someone could run a 250 to death in 11,000 miles.
 

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spark plug shouldn't be wet. If its wet its not firing. Try taking your spare plug and put the bike wire on it and lay the plug against some bare metal for ground ad see if there's a spark when cranking. If no spark could be coil or plug wire.
 

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spark plug shouldn't be wet. If its wet its not firing. Try taking your spare plug and put the bike wire on it and lay the plug against some bare metal for ground ad see if there's a spark when cranking. If no spark could be coil or plug wire.
Thanks for the suggestion, but I've done this and as Ive said the spark plug fires.
 

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not real keen on a spark plug a few threads from out..
fuel pump is in petrol tank, whatever the previous owner
was putting in there, low fuel levels are more likely to
draw any particulate matter etc into the system..
ecu reset involves little and could be worth doing..

contacting servicing dealer could be interesting,
altho the loose spark plug dosnt inspire confidence..

despite some cutting out issues with cbr250r
which seem to be related to sensors/mapping/ecu etc,
and the search for high fuel economy [lean state],
we have a new engine designed by honda, designed for
this motorcycle, so despite your problem i wouldnt be
thinking of your motorcycle as a lemon..

it has a problem, to be corrected or repaired,
which may mean the hands of a honda mechanic..
whoever you use, impress upon them your attitude to
and need for understanding of the problem/fix..

[use 91ron unleaded no ethanol petrol if possible]
 

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:( I was afraid I was coming to the end of my troubleshooting abilities in my garage, I think I will have to take it into the dealer.

I guess the fact that it died on the freeway and the sparkplug/fuel was not the cause throws up some major red flags. Hopefully I don't need an entire new motor, but its just hard for me to believe someone could run a 250 to death in 11,000 miles.
Well, the fact that the spark plug was loose (you said it was only hanging on by a few threads) creates a couple issues, one being that the compression would have been very low as a result of the spark plug not sealing the combustion chamber, and the second being that the location of the spark plug electrodes would have been up inside the plug hole, instead of in the main part of the combustion chamber, which is not ideal for proper combustion to take place. That the spark plug was extremely loose and hanging by a few threads, is more than likely the reason the bike died on you. The question now, is what subsequently happened inside the engine that is preventing it from restarting. Anything beyond what we know right now is just speculation, and pretty much a waste of time. The next logical step would be having the compression tested. The compression test should then answer the question as to whether the next step would involve disassembling the top end of the motor for a close inspection of the components.

I wonder how many other CBR250R's might be running around out there with loose spark plugs, maybe even on the verge of falling out?... Perhaps something to consider checking?
 

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Well, the fact that the spark plug was loose (you said it was only hanging on by a few threads) creates a couple issues, one being that the compression would have been very low as a result of the spark plug not sealing the combustion chamber, and the second being that the location of the spark plug electrodes would have been up inside the plug hole, instead of in the main part of the combustion chamber, which is not ideal for proper combustion to take place. That the spark plug was extremely loose and hanging by a few threads, is more than likely the reason the bike died on you. The question now, is what subsequently happened inside the engine that is preventing it from restarting. Anything beyond what we know right now is just speculation, and pretty much a waste of time. The next logical step would be having the compression tested. The compression test should then answer the question as to whether the next step would involve disassembling the top end of the motor for a close inspection of the components.

I wonder how many other CBR250R's might be running around out there with loose spark plugs, maybe even on the verge of falling out?... Perhaps something to consider checking?

Hey Mike, I appreciate the additional input. And also @Shinosin above thank you for the input about the ECM being a possible factor.

Is it normal for the check engine light to be lit while I am trying to start, or does that signify a problem? The check engine light is off when I turn the ignition key to on, but once I hit the start button to crank the starter the check engine light comes on.

If this is irregular during starting than it leads me to hypothesize that the ECM sensed the loss of compression when the spark plug was loose, shut the motor down, and now will not allow it to restart until it is reset... But that could be way off.

Will someone let me know if their check engine light is on during starting?
 

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Hey Mike, I appreciate the additional input. And also @Shinosin above thank you for the input about the ECM being a possible factor.

Is it normal for the check engine light to be lit while I am trying to start, or does that signify a problem? The check engine light is off when I turn the ignition key to on, but once I hit the start button to crank the starter the check engine light comes on.

If this is irregular during starting than it leads me to hypothesize that the ECM sensed the loss of compression when the spark plug was loose, shut the motor down, and now will not allow it to restart until it is reset... But that could be way off.

Will someone let me know if their check engine light is on during starting?
Just went outside to the shed. Started the bike and yes as soon as i turn the key and the rpm gage flicks around the check engine light is on but goes off when the needle is back at 0
 

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Just went outside to the shed. Started the bike and yes as soon as i turn the key and the rpm gage flicks around the check engine light is on but goes off when the needle is back at 0
Thanks Swift, there goes that theory I guess.

Anyone out there knowledgeable about the ECU (ECM) and if trying a reset is worth a shot? I don't believe it could hurt anything but the problem is that resetting the ECU requires turning on the bike.......
 
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