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Discussion Starter #1
Hello all, my bike wont start so I looking for help with this problem.

Symptoms
Turn the ignition, switch to ON,...I can hear the fuel pump priming..., hit the start button and the engine just turns as if it had no gas. I have almost half tank of gas. I also tried starting it with the throttle fully open, just in case it was flooded, no luck,... the sound of the engine did not change at all while it was turning over.

I have checked the following:
Air filter looks clean and I do have a good spark. While the spark plug was out I pushed thick shop towel inside the spark plug hole and as I turned the engine the towel was blown out easily, which indicates some sort of compression at the very least.
When I inspected the spark plug I found it to be a bit dry than what I would expect it to be after multiple start attempts…. I am not a mechanic and I’m only going by my intuition…. the gap was measured to be .89mm with wire type gauge.
Since I had the tank propped up I took the IACV valve out and tested it. It did it’s rotation when ignition was turned to ON position.
So I was suspecting that the fuel was not getting into the combustion chamber… I decided to test if the fuel injector was spraying the fuel while out of the engine. I unscrew the two screws holding the injector and when I turned the ignition to ON the pressure in the fuel line simply separated the fuel injector from the end cap which is attached to the hose and lot of fuel spilled on the bike...VERY DANGERS DO NOT REPEAT THIS TEST. Besides scaring the s**t out of me, this test did prove that I do have some sort of fuel pressure right at the input of the fuel injector. I don’t see how I can test if the injector is spraying the fuel???? Holding the fuel injector and end cup with my hands is not safe at all.

The bike has 10,000km and it ran fine last ride three weeks ago where I did a 500km trip. I did 200km on gas that I currently have on the bike so I don’t think that the gas went bed after such little time.

I would like to spray the starting fluid into the intake and that will tell me if the problem is in fact with the lack of fuel in the cylinder. What type should I be using since this is a FI bike?
What do you guys suggest as for my next step?
 

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Does your Check Engine Light go out after the fuel pump cycles and the tachometer completes its sweep, or does it stay on?
 

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Sounds like it sat for three weeks correct?
I had problems starting after letting my bike sit for 2 weeks. Took several tries to start her up. Seemed like some type of fuel/vapor lock. You may also have a low battery, consider a battery tender while not riding for over a week especially during cold weather. Dim headlight is a good indicator if you cant get a voltmeter or to a service shop to check.
 

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Discussion Starter #4
Does your Check Engine Light go out after the fuel pump cycles and the tachometer completes its sweep, or does it stay on?
The check engine light goes OFF after the fuel pump cycles, every time. It never stayed on.
 

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Discussion Starter #5
Sounds like it sat for three weeks correct?
I had problems starting after letting my bike sit for 2 weeks. Took several tries to start her up. Seemed like some type of fuel/vapor lock. You may also have a low battery, consider a battery tender while not riding for over a week especially during cold weather. Dim headlight is a good indicator if you cant get a voltmeter or to a service shop to check.
I forgot to mention that. I have and currently am using the battery tender so the battery is fully charged.
I have been cranking on the engine at least 30 times for few seconds each try. I even tried open throttle encase the engine was flooded.
 

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try turning on the bike, letting it go through it's start up sequence and then turn it off. Do this about 10 - 15 times, then try starting it. It could be that the fuel lines have drained back into the tank and need to be refilled before the bike will start.
 

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When checking the spark at the spark plug. You need a spare spark plug. By removing the spark plug, the engine will rotate very easy. This is an abnormal test for checking for spark. By using a spare spark plug. This will keep the engine in a normal starting routine. Ensuring that the ignition system is operating as it is suppose to.

When an engine is not operated for a period of time. Longer than a few days. The oil that is coating the rings and piston drains back into the engine sump. Resulting in lost of compression in the combustion chamber. Downward motion of the piston is not able to create a low pressure area inside the combustion chamber. Resulting in no air/fuel mixture being sucked/pushed into the cylinder.

With the spark plug removed. Inject 2 to 3 teaspoons of engine oil thru the spark plug hole. Temporary install the spark plug finger tight. Spin the engine over for 10 seconds with the starter. Remove and clean the spark plug, with a chemical. Gas, lighter fluid, choke cleaner or brake clean etc, etc.

Reinstall spark plug, try and see if the engine will start.

Another piece of information to consider. Gasoline will change from a liquid to a vapor at -16 deg F (-26 deg C) under normal conditions.

With the Dead Head Fuel System (no fuel return hose from injector to fuel tank) on the cbr. When the cbr is left sitting idle for a period of time. The gas in the line from the fuel pump to the injector will turn to vapor and be returned to the fuel tank when the pressure is above 43 psi. If the cbr is left idle for 3 weeks. There is a good possibility that the line from the fuel pump to the injector is filled with fuel vapor.

As mention above. Cycling the Key to let the fuel pump operate a few times should help. The fuel pump is a low volume, high pressure type. Volume, 2.34 oz (69.2 cc) in 10 seconds. How much fuel or vapor is in the line from the fuel pump to the injector?
 

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You could try this
http://www.ebay.com/itm/Gunk-M3515-Instant-Starting-Fluid-11-Oz-Aerosol-HIGHEST-ETHER-CONTENT-/271283680076?pt=Motors_Automotive_Tools&hash=item3f29c4734c&vxp=mtr

You seem to have proved that you have a spark and fuel to the injector. I think the self diagnostic would probably show a faulty injector on the engine fault light so, barring a major mechanical failure such as valve gear problems you should first make sure the air flow through the engine is working - no blocked intake or exhaust ( vandals can sometimes do this).

The ether spray should at least fire the engine for a second or two and if it doesn't keep running you would be sure that fuel delivery was the problem.

Regards Roadster
 

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If you can easily get at your spark plug to momentarily remove it try putting
a small amount of gas into the hole. Put the plug back in and try to start the engine as usual, in as short a time as possible. If it fires and tries to run briefly you probably have a fuel / fuel delivery issue.
Having not started the engine for three weeks should be no issue, something else is wrong.

Rick
 

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Honestly if you haven't tried it already, I'd give push starting it a go. A year ago my battery hit critical (sat too long) and the bike died after starting. Charged the battery to 100% and even had it load tested, and bike would only charge the pump and attempt to start (you'd hear it crank), then nothing.

I was going to start pulling things apart or have it towed, but someone said to try push starting so I gave that a go and it fired up immediately. To do it, simply find a decent stretch of straight road (NOT BUSY AT ALL), put the bike in second (key ON and killswitch to run), and run alongside it clutched in up to around 5-10km/h. Once at that speed, drop the clutch and try to keep your speed up, and the engine should begin to catch then start. As soon as it does, clutch back in, come to a stop, and put it in neutral.
 

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just one addition to clutch starting tho,
best [imo] to jump onto the seat
when going as fast as you can run
alongside, then and as your weight
transfers to the motorcycle, drop clutch..

if thats not possible for you, probably best
to enlist someone to push you while on
the motorcycle, then in one action lift up
and drop down onto the seat as you drop clutch..

this gets the best result for weight transfer
and momentum at the moment the engine tries
to fire and start.. also most stable compared to
running alongside the motorcycle when it does
fire and start sending power to the wheel..
[and best position for controlling the clutch etc]
 

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If you can easily get at your spark plug to momentarily remove it try putting
a small amount of gas into the hole. Put the plug back in and try to start the engine as usual, in as short a time as possible. If it fires and tries to run briefly you probably have a fuel / fuel delivery issue.
Having not started the engine for three weeks should be no issue, something else is wrong.

Rick
... or take out the air cleaner and spray in some fuel. Engines will generally fire on fuel practically dribbling in when cold!
 

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Honestly if you haven't tried it already, I'd give push starting it a go. A year ago my battery hit critical (sat too long) and the bike died after starting. Charged the battery to 100% and even had it load tested, and bike would only charge the pump and attempt to start (you'd hear it crank), then nothing.

I was going to start pulling things apart or have it towed, but someone said to try push starting so I gave that a go and it fired up immediately. To do it, simply find a decent stretch of straight road (NOT BUSY AT ALL), put the bike in second (key ON and killswitch to run), and run alongside it clutched in up to around 5-10km/h. Once at that speed, drop the clutch and try to keep your speed up, and the engine should begin to catch then start. As soon as it does, clutch back in, come to a stop, and put it in neutral.
I'm not understanding how a bike with a fully charged (and load tested) battery won't start using the starter motor, but will fire up by bump starting.
 

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I'm not understanding how a bike with a fully charged (and load tested) battery won't start using the starter motor, but will fire up by bump starting.
To be honest I'm not sure either, all I know is it worked. Even took the battery into Honda and they tested, charged, and returned it saying it was 100% charged and healthy (after which I put it on my own charger/tender overnight), and the bike would still crank and crank but not turn over. Push starting it worked on the very first go, and no issues since (was over a year ago).
 

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Discussion Starter #16
update...

I removed the exhaust hoping that my problem was due to kids stuffing something in it causing a blockage. Bike did not start.

@JME250RA - I tried turning the ignition ON (without starting). I did that exactly 20 times and than I tried starting the engine - no luck, no difference

@Roadster - I removed the air filter and I sprayed the ether spray in. It did not work. I sprayed it again and this time I opened up the throttle fully as the engine was cranking.... I got a very nice back fire through the air intake and the bike caught a small fire. I had to use an extinguisher to put it out.... Holy f**k this is a 2nd close call. By the third time I just may blow up my house...

So, I guess this backfire may indicate a intake valve that is not closing???

Other than running a proper compression test, what are my options now?

One more think, I noticed that all that cranking has somewhat reduced my oil level. the sight glass is showing it lower than the MIN bar.
 

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as youve tried all these options, try this, cant hurt;
switch ignition on, then lightly quickly brush starter
with finger or thumb as if by accident, after a few secs
hit the starter as for normal startup..

shoot me for a fool but cant see how cranking
would reduce oil levels in any significant way..
[good luck]
 

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High Explosive Chemical.

I removed the air filter and I sprayed the ether spray in. It did not work. I sprayed it again and this time I opened up the throttle fully as the engine was cranking.... I got a very nice back fire through the air intake and the bike caught a small fire.
So, I guess this backfire may indicate a intake valve that is not closing???

One more think, I noticed that all that cranking has somewhat reduced my oil level. the sight glass is showing it lower than the MIN bar.
Ether will self ignite with the heat of compression. Remember that the intake valve is opened 5 Deg before TDC on the Exhaust Stroke and the ECM/ECU also fires the Spark Plug on the Exhaust Stroke.

Cold oil does not flow very well. It will take the oil that is pumped to the Valve Train a little longer to return to the Engine Oil Sump.

.
 

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Discussion Starter #19
Ether will self ignite with the heat of compression. Remember that the intake valve is opened 5 Deg before TDC on the Exhaust Stroke and the ECM/ECU also fires the Spark Plug on the Exhaust Stroke.

Cold oil does not flow very well. It will take the oil that is pumped to the Valve Train a little longer to return to the Engine Oil Sump.

.
makes sense, thanks for the info.
 
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