[The Mex]

One of the lads on the 900R OC put this up (XJS36UK) and I thought it might be worth putting up here for anyone interested.

(He has given his permission )


In the simplest of terms a coil is a step up transformer.

I.e it takes 12 volts and turns it into something like 24,000 volts.

It's these sorts of voltages necessary to make a spark jump a gap of 1-2mm (so just think how many volts are in a bolt of lightning !)

How it works is quite indepth physics, but again the simple aspect is you have to sets of electrical windings, the first set which receives the 12v supply would be something like 100 turns of wire over a 1 inch diameter using a relatively low resistance 0.5mm wire, this then leads directly to a second winding of say 1000 turns over a diameter of 2 inches using a 1.5mm medium resistance wire, this then feeds the plugs directly through the HT leads.

Effectively the charge comes into the first set of windings and as it travels along the path to the second larger set of windings where it accumulates before a switch (signal from the pulser) closes the earth circuit (Plugs) the resultant rush of strored charge is released in one go and provides the spark.

(Note to the tech guys, none of these figures are representative of the 900 or any other bike, they're purely to explain how a coil works)

With ZZR coild and Dyna coils etc, you're basically talking higher output voltages say of 36,000 volts, which basically means the spark is more able to jump the gap on the plug and is less likely to be snuffed out by the mixture in the combustion chamber, resulting in a much reliable spark more complete combustion of the mixture and therectically more power, but this may be slightly negated by the increased combustion temperature which comes from more complete combustion (around 60% of the petrol/gas in the combustion chamber is actually there to cool the piston crown rather than explode), which in turn equals more friction, etc etc.
Generally speaking though it's unlikely you'd see a huge difference of a standard set-up with everything working properly.

Now where did I put my anorak........

This post has been edited by The Mex: 02 July 2008 - 03:39 PM

[Kelpie]

Thanks for that! Interesting stuff. I was afraid we were going to have a lecture in birth control for a moment!

[The Mex]

Kelpie, on Jul 2 2008, 04:57 PM, said:

I was afraid we were going to have a lecture in birth control for a moment!

I've sent Mark (XJS36UK) a link to this thread!

He might have some info on that front too.... but it's not something that has ever come up in any discussion before now!!

You mad Scots loon Kelpie!

This post has been edited by The Mex: 02 July 2008 - 04:49 PM

[Tenmill]

Wot's a volt?

[The Mex]

Tenmill, on Jul 2 2008, 06:00 PM, said:

Wot's a volt?

Just googled it for you and discovered that.....



It's a restaurant!

[Tenmill]

So, it makes food into more food? I can see how this is a good thing.

[Fr Dougal]

The Mex, on Jul 2 2008, 04:37 PM, said:

In the simplest of terms a coil is a step up transformer.

I.e it takes 12 volts and turns it into something like 24,000 volts.

It's these sorts of voltages necessary to make a spark jump a gap of 1-2mm (so just think how many volts are in a bolt of lightning !)

Hmmmm, so that explains how I can touch both connections on a 12volt battery but when I stupidly tried to pull the lead off a spark plug.........................
while the f*****g car was still running.....

[limerick bandit]

Fr Dougal, on Jul 2 2008, 06:29 PM, said:

Hmmmm, so that explains how I can touch both connections on a 12volt battery but when I stupidly tried to pull the lead off a spark plug.........................
while the f*****g car was still running.....

its so funny when someone tries to do that

thanks for that mex

[The Mex]

Fr Dougal, on Jul 2 2008, 06:29 PM, said:

Hmmmm, so that explains how I can touch both connections on a 12volt battery but when I stupidly tried to pull the lead off a spark plug.........................
while the f*****g car was still running.....

I discovered that before I was 10 years old!!

[scrapheap challenger]

What about the ill fated adjustable resistor coil it still hides in my pocket covered in fluff since i butchered a whole loom good for the soul that was and replaced the entire lot with a super duper 12v upgrade from 6 v one consisting of electronic ignition etc including a custom made ht coil and most of the wiring was obtained from skips(Moral of this is get bin hoking for parts}.
But you are correct mine is pumpin out huge voltage though when u get an eletric shock from even the we 6v bantam it hurts

[Fr Dougal]

The Mex, on Jul 2 2008, 07:01 PM, said:

I discovered that before I was 10 years old!!

Yeah, I was about 10 but I remember it like yesterday

[John Bulleteer]

The Mex, on Jul 3 2008, 01:37 AM, said:

Now where did I put my anorak........[/font]

Not at all !
That was well explained Mex.
Bulleteer.

[TheBogieMan]

Most enlightening I think this sort of thing should be stickied or put in a locked thread in it's own section

I remember in the distant past doing a similar thread explaining how regulators and rectifiers work.


Shall we join evil forces Mex and fill people brains with "Dah knowledge"

[Larry]

Thanks El Mehicano. Thats a very good explanation. I finally understand why grabbin the H.T lead stings so much.

[The Mex]

Really nice to see all the positive replies!

Good to be learning something new....

The words aren't mine though... as mentioned earlier they are taken from a thread on the GPz900R Owners Club forum....

I just asked Dave (he who wrote it) if I could take it and post it here seeing as it was worded so well!
(It's only up a few hours and has had 110 views)

@ Bogie. Thread stickied!
We'll have to put our heads together some day and make this a better resourse!
I'm all up for sharing knowledge!

[The Mex]

TheBogieMan, on Jul 2 2008, 09:15 PM, said:

I remember in the distant past doing a similar thread explaining how regulators and rectifiers work.

Want to go find that and put up a post about it?

[TheBogieMan]

The Mex, on Jul 2 2008, 11:14 PM, said:

Want to go find that and put up a post about it?

I can't remember if it was on here or 'the other place', it was is response to a thread about a constantly dead battery

[The Mex]

TheBogieMan, on Jul 3 2008, 07:52 AM, said:

I can't remember if it was on here or 'the other place', it was is response to a thread about a constantly dead battery

Had a little look but can't find it here......

Wil give a longer look when I have more time...

[Larry]

TheBogieMan, on Jul 3 2008, 07:52 AM, said:

I can't remember if it was on here or 'the other place', it was is response to a thread about a constantly dead battery

Sounds familiar so it must have been here

[TheBogieMan]

found it here ! was a reply to a question by Father D, I'll tidy it all up and bunt it up as a new post