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Discussion Starter #1
I was doing my P plater test today, and one of the guys was telling me if i put the spark lead again the chassis to get an arc i would short the bike and blow something. I cant get any spark and tested it buy trying to get an arc, is it true that testing it this was will damage it? The bike is back firing and he said that was a sign the ECM was blown.
 

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ECM = Electronic CounterMeasures, a jamming device to block laser and radar signals (the shit they put in fighter jets to stop missiles homing in on them etc). If your bike has one of them, I'll give you $50 for it :p

Justin.
 

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Discussion Starter #3
sir.b said:
ECM = Electronic CounterMeasures, a jamming device to block laser and radar signals (the shit they put in fighter jets to stop missiles homing in on them etc). If your bike has one of them, I'll give you $50 for it :p

Justin.
LOL please excuse my newb chat, still learning
 

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Nah that's cool mate, I just thought it was cute :)

I think you were probably looking for the more commonly used ECU, which is Engine Control Unit, aka the computer. The CBR250 doesn't have an ECU/ECM as such, it uses a CDI (which can stand for Capacitor Discharge Ignition or Circuit Discharge Ignition, if I remember Eclipze's comments correctly the CBR has the latter) to control the spark.
Justin.[hr]
smiley_666 said:
Electronic Control Module...
True, CCM too, but the ciblet doesn't have any of them.

Justin.
 

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Discussion Starter #6
so when i put the lead against the chassis to see if there was any spark i could have blown the CDI? its weird, i stupidly forget the kick stand was up and went to put the bike down, had to lower it slowly to the ground. Picked it back up and it would start, just sounded flooded and kept back firing.
 

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snake952 said:
so when i put the lead against the chassis to see if there was any spark i could have blown the CDI? its weird, i stupidly forget the kick stand was up and went to put the bike down, had to lower it slowly to the ground. Picked it back up and it would start, just sounded flooded and kept back firing.
Nah I don't think you'll have a blown CDI, never heard of anyone having a problem through grounding the spark.

Pretty common for bikes to not want to start after they've been layed down mate. First thing to do is check your airbox for oil (take the tank off).

Justin.
 

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There's a ventilation tube (crank case breather tube) that runs up to the airbox. When the engine is on its side, the oil can go up this tube into the airbox. If this has happened, you'll need to clean it out.

Edit: How long was it on its side for? Also, don't clean it out with any nasty chemicals, whatever you put in your airbox will end up in your engine. I'd just wipe it up well. You may need a new air filter also.

Justin.
 

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snake952 said:
ah ok, but im still not getting any spark from the leads
If the bike is backfiring when you crank it then I'm pretty sure that means you're getting spark, what else is making the fuel burn to cause the backfire?

Can you describe in detail how you tested for spark?

Justin.
 

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Discussion Starter #12
pulled the lead out and put it close to the chassis to see if there is an arc, same as i always have for a car
 

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snake952 said:
pulled the lead out and put it close to the chassis to see if there is an arc, same as i always have for a car
Ahhh, the electrical systems of cars are a lot stronger (when cranking). Actually ground the tip (use the engine) and look for a spark between the tip and the electrode.

Justin.
 

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Discussion Starter #14
ok ill give that a go, thanks for the tips guys. I just got my p's today and i cant ride, its pissing me off
 

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im guessing that the cbr's leads are better insulated than the car ones youve tested. you can put a plug in the end of it and hold that against the chassis, then you may see if you have spark
 

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smiley_666 said:
im guessing that the cbr's leads are better insulated than the car ones youve tested. you can put a plug in the end of it and hold that against the chassis, then you may see if you have spark
Pretty sure it's actually that in a car you get less voltage drop when you crank it. Guessing the leads are the same.

Justin.
 

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anyway, needs a plug in it if the spark isnt showing up without one
 

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Yes yes, I meant with a spark plug attached. I didn't even realise there wasn't one attached in the test snake did originally, I've never tested for spark without a plug even in a car...

Justin.
 

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CDI can stand for either Capacitor Discharge Ignition or Circuit Discharge Ignition. CBR250's have the circuit discharge type, also known as transistor type ignition.

If you have a spark plug loaded in the lead, ground the body of the spark plug against the engine and crank... you get a spark. That's not going to do any damage the electrics, because it's doing it's normal thing... sparking as designed. But if you don't ground the spark plug body to the engine, then you're getting the circuit to dump a whole lot of energy nowhere... and the electrics won't appreciate it! BUT... CBR250's have wasted spark ignition. So if you fail at doing it properly with one spark plug, I doubt it would cause any problem... as the other spark plug is going to do it's thing and dissipate the energy in a spark :)

So I doubt you would have kill the CDI from messing with just one spark plug/lead ;)

FYI... Normally (with engine running), it's only the cylinder that's under compression that will actually have a strong spark. The high ion concentration with the pressure makes that cylinder a lower resistance to dump the energy... compared to the exhaust gas in the other (which may just have weak spark).

As for why it's not sparking now... check the usual suspects. Sidestand light working? Bike in neutral, kill switch off... tried with clutch in, sidestand up? You haven't flatten the battery to far playing around with all this!? Fuses ok?
 

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Discussion Starter #20
Eclipze said:
CDI can stand for either Capacitor Discharge Ignition or Circuit Discharge Ignition. CBR250's have the circuit discharge type, also known as transistor type ignition.

If you have a spark plug loaded in the lead, ground the body of the spark plug against the engine and crank... you get a spark. That's not going to do any damage the electrics, because it's doing it's normal thing... sparking as designed. But if you don't ground the spark plug body to the engine, then you're getting the circuit to dump a whole lot of energy nowhere... and the electrics won't appreciate it! BUT... CBR250's have wasted spark ignition. So if you fail at doing it properly with one spark plug, I doubt it would cause any problem... as the other spark plug is going to do it's thing and dissipate the energy in a spark :)

So I doubt you would have kill the CDI from messing with just one spark plug/lead ;)

FYI... Normally (with engine running), it's only the cylinder that's under compression that will actually have a strong spark. The high ion concentration with the pressure makes that cylinder a lower resistance to dump the energy... compared to the exhaust gas in the other (which may just have weak spark).

As for why it's not sparking now... check the usual suspects. Sidestand light working? Bike in neutral, kill switch off... tried with clutch in, sidestand up? You haven't flatten the battery to far playing around with all this!? Fuses ok?
Thanks for the info, i have tried the kick stand and all the usuals. Ill take the tank off and check for oil in the air filter.
 
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