I was riding my bike the other day listening to some music through a Blootooth connection from my phone to the intercom when the album ended and there was silence. Well, there should have been silence, but I could hear apparently random clicking sounds. I guessed it was being caused by HT voltage leaks from the ignition system. So your write-up couldn't have come at a better time!

I have now ordered some CBR 929 coils and loom and am waiting for them to arrive so I can do the conversion. Can't wait.

Thanks for your posting - it was something I had never thought of and I would otherwise have fitted a set of replacement used leads - probably with similar or even worse problems.

Well done - and if you are ever in the uK let me know so I can buy you a beer!

 

A brilliant idea for an improvement to our CBR 1000F bikes. I have ordered some CBR 929 coils and loom and can't wait to fit them.

But having looked at the wiring diagram, it seems that one of the stick coil pairs is wired the wrong way around - so the spark will go the wrong way in the spark plug causing wear on the side electrode instead of the centre one. Not a complete disaster, and the bike will happily run like that, but it will run better with the spark going the right way.

Soooooo, here is a modified version of the original diagram - it's always much easier to improve on something than to create it from nothing in the first place, so all credit to SB for his orginal!

Cheers

 

Mines simple 2 positives, "+" for 1/4 , "+" for 2/3, single common "-" ground for all. Right side old neg left unused

After that it's how fancy you want to be laying out soldering and wrapping it all up

 

Ah, I see what you mean - much simpler and I guess neater too! No doubt you checked that the resistance of your coils is high enough wired in parallel instead of in series. It's a much neater wiring solution - which high resistance coils did you use?

 

Hey, is this mod still working? I checked the schema and it seemed flawed, kind of... You have connected the two series coils in a way that one coils ignition spark energy goes thru the other coils primary windings. Resulting in that coils primary windings get both it own and the other coils spark energy going thru the primary part of that coils windings.

I think that it should be connected so that the two coils should be connected together from the negative poles. That way the ignition pulse goes thru the both primaries at the same time, no double pulse strength for either of the coils. And the circuit is more similar to the original double output coils.

And by negative pole I mean that pole of the primary which has higher resistance when measured against the HT output to the spark plug. I know that it can't be measured with normal multimeters resistance mode. Perhaps it can be measured by connecting low voltage (maybe 1V) between HT output and one of the primary inputs. And then measuring voltage polarity of the remaining primary input and doing some reasoning...

Am I wrong or am I wrong?

Ordered CBR929 stick coils and going to try them out when they arrive.

 

Hi,

I'm not certain what you are asking here, but I'll do my best to answer your question anyway!

In the original set-up, there are two coils, and each one fires two plugs simultaneously. One spark ignites the mixture in that cylinder, and the other spark is just wasted. On the next revolution, it is the other way around. In the new system, there are now separate coils for each spark plug, but are wired so that two still fire at once, one igniting the mixture, the other wasting a spark. This is important as the bike's ECU is configured to work that way. The resistance of the new coil pair should be around the same value as the resistance of the original single coil or there is a risk of overloading and burning out the ECU. The 929 plug sticks are around half the resistance of the original coil, so wiring them in series means that the total resistance of the pair is around the same value as the original coil - as needed.

Hopefully you have also bought the loom to go with the sticks. Simply strip off all the coverings to expose the wires. You will see a black and white wire coming from each stick. This has the same function as the B/W wire in the original loom. Follow the wiring diagram I posted to connect the coils, and you should end up with 3 wires coming out of the loom - one B/W (you can solder the two together), one blue / yellow, one yellow / blue.

On the bike, follow the loom with the 4 female spade terminals that connected to the original coils and you will see it terminates at a connector with a milky clear covering. Remove this connector and the loom and strip off all the coverings. You will see where the B/W wire is spliced into 2. Cut all the wires just before the split. Now solder these 3 wires to the 3 wires coming out of your new loom (checking you ahve enough length to reach the connecting block). Now you are done! Tidy up and start your bike, and enjoy a 10 year advance in ignition technology!

 

Yep! Your correct. I had to go back and check SB's job. He needs to switch his yellow and green wires on 2&3 coils. (sorry SB)
SB can simply switch them out with the blade connectors meet the original wire harness.

The soft ground electrode will not take the punishment that the harder center electrode will.



edit: The polarities are correct in his diagram but the wire colors aren't. The top two colors need to be switched. B/Y should be + and B/W should be -.

 

ok!
if i've read these posts right the (polarity) going through the spark plug is wrong?
i cannot see it!
if we have 12v going to the coil for H V to the plug,ie the output of the coil is going to the center/top connection of the spark plug?
and the earth is the engine?
maybe i'm confused!
would not be the first time.

 

^ Its a little more involved than that.

Apparently, its easier to get electrons to make a jump from a hot surface than from a colder one. I have read that it takes up to 45% more power to make the jump in the other direction. That's why the center electrode is insulated, to make it hot. The center electrode is - in charge and electrons flow from - to +. Therefore the electron flow is from the center electrode to the ground electrode and use the engine head as a path to flow back to the + side of the secondary coil. When the charged electrons make the jump from the center electrode they take a tinny piece with it.

There is also the shape of the plasma arch. The heat and shape of the arch is dependent on the polarity of the jump.

 

timbuctwo,
i don't know how many times ive read your response,
but you're way over my head!
i still can't see a problem with what i said, and the original setup from S B.
thick...