white wire magneto unravelled. something peculiar.

lol, getting back to that 16 bit processor with espresso machine and five repeateable alarms, arent we? :giggle:


one, i personally think most of this nonsense on advance curves is just that. there, i said it.

yamaha, kawasaki, honda...bultaco, gas gas, HD, suzuki, nsu, sachs...dolmar, stihl,mcculloch, shindaiwa,robin.... not one user settable cdi amongst them as a standard item. all on engines with a lot wider power band than a cruddy little HT.

i will admit that there are major faults with the HT, that makes cdi changes necessary. this thread was started because of one!

aforementioned companies actually paid people to design their circuits. use quality components, use one supplier of a certain component.

i reckon its safe to say (ive never done it!) that if you strobed ten HTs, not one would have the same advance curve or initial timing. there is just so much "slop" in the system!

im not arguing against jags cdi unit either. in a way, i do feel its masking what may be a fundamental flaw though.

now ive done this, im wary of assuming each HT will produce the same voltages, the same trigger point, or that the cdi is internally identical.

by allowing you to change the timing, you can nullify any inaccuracy in the stock system. therefore, better running.

doesnt fix the basic flaw :(

who is to say the newer style coils dont have 1000 more windings? that would make a higher voltage, and if the cdi hasnt been modified, then its too advanced, or if they have and you use an old coil then it will be way retarded and... until i burn a new coil out, im not finding out either!

maybe the flaws fixed. but then, i want my power for lights! red ones! white ones! those 4w mr16 LED replacements are amazing!

to the ratcave!!

gone.
 
what i meant say, before i got carried away...

what you should try fabian, is a seperate coil, with both ends attached to plug.

twin spark, seeing as you have the heads to do so.

or i should shut up, experiment and sell you one ;)
 
one, i personally think most of this nonsense on advance curves is just that. there, i said it.

The reason why Jaguar's CDI is so effective is that it allows you to change the advance curve when messing around with different compression ratios and different fuels.

Your chainsaw etc has a fixed compression ratio set by the factory. The guys who modify chainsaws for racing competition also mess around with different ignition systems as the standard item is not suitable outside of a stock setup.
 
The reason why Jaguar's CDI is so effective is that it allows you to change the advance curve when messing around with different compression ratios and different fuels.

exactly. i just think it masks a manufacturing fault within the standard engine before any mods are even contemplated as well ;)

im still not buying one :giggle: ive always been happy with my cdi itself. this magneto thing is another matter entirely and sheds new light on the situation in my mind.


my chainsaw? MY chainsaw is stihl in pieces and is starting to get a pipe! heh heh heh. waiting on a bigger bore/piston :)

those unified cdi affairs arent quite so easy to um...unmake by the looks of them. i recall cutting one in half once...
 
im still not buying one :giggle: ive always been happy with my cdi itself.

Great, then make a new twin coil and CDI that will run a twin spark plug cylinder head, and give it multi advance curve functionality, upon which i'll hapily fork out the cash to install it on my bike.

Now we are both happy: you get to mess around with ignition systems and i get to use an extra spark plug.
 
first experiments with a bare minimum of components, and viola. we have spark , starting and a nice wind out :) way more spark energy than the stock thingy.

running off a transformer, i was getting spark at 15v...whereas the HT box wont do anything even at 30!

and will run any coil! anything from something i pulled from an old briggs and stratton, to a big fat lucas auto one, to the tiny lil pitbike one i finalllllllly found after searching for hours...


the dyno is calling. dyno, with strobe, and hooked up to the oh-so-silly-scope :)
 
I am feeling a little small below all these senior member posts :geek:
Smashed apart a standard CDI disappointing as cello-tape insulation in the igntion coil
2013-11-02_18-05-55_995.jpg
I have rewound voice coils for speakers before and have pictures of my first attempt it still works great, the best results are however achieved in a vacuum. You can improvise a chamber no fuss with a large jar and easily available parts.

Did you rewind the magneto coils or just use the cdi from the schematic.
HMMMM COPY COPY !?!
If rewinding coils and customizing a cdi is there anything to be gained adding a third triggering coil and then customizing the cdi to match.

I would really like to gain some extra power on the spare coil. Headlight, some hot-grips for cold days and the ability to charge my phone not necessarily all at the same time.
 
dont feel too daunted. i only got to senior by dribbling cr4p :)

the vacuum is the ideal way to pot coils, but is a bit advanced for the basic magneto coil.

dont worry, cellotape is standard in most transformers. beats brown paper ;) id prefer seeing mica tape for a hi tension coil myself though.

yes, i copy :) i did rewind a coil but never went as far as to reassemble it.

the extra trigger coil is the real answer but is only feasible as a one off, unless one gets new laminations made up. then theres timing it, possible replacement of the magnet, etc etc.

phone, yes. gps, yes. LED headlights, yes...

hot grips running from around 4 to 8 amps? no chance. not without strapping on a small alternator...
 
I have seen a go kart running on methanol using a third winding a long time ago looked similar in design and size.

Next strange question would neodymium magnets in the flywheel be any good i have a large selection.
 
Back
Top