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#Post#: 7663--------------------------------------------------
CDI ignition
By: Jimr1999 Date: September 30, 2022, 5:42 am
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Morning all, and here I go again experimenting.
This is a winter project for me on the engine.
The aim is to widen the power band of the engine by having self
advancing timing as the revs build, Like most motor vehicles.
Peak power should not be effected as our engines are designed
stock to only produce peak power at about 3500 revs.
Quite a few people add 4[sup]0[/sup] of advance by filing the
key. I have not. Doing this shifts the peak power up the rev
range.
with a 7:1 gearing plus TAV overdrive at 1:1, 6000 revs would
give approximately 60mph!!! on a 17" wheel + tyre so our rev
range for power is probably best low down, and ideally over as
wide a band as possible. If I were a Kart with small wheels,
filing the key would be a great advantage where I needed it as
the gearing is lower. As we state 35mph as an aim for the
CycleKarts, having a wide band of power around 3500 revs should
be the aim.
I have come across a fellow in Canada who is producing basic
CDI kits for our engines and persuaded him to ship me one.
If it works it should put less stress on the engine, have a
better fuel economy, a wider power band, wider torque band and
be easy to start.
These things are quite new and the fellow is a small business
trying to establish a market. It is an experiment and I may go
back to stock if it doesn't work out. If I were you and you were
thinking of giving it a go, I would let me spend the small
amount of cash on it first and see how it works out.
Thoughts please
HTML https://www.youtube.com/watch?v=NNaAdmFazp4
#Post#: 7664--------------------------------------------------
Re: CDI ignition
By: Moogie38 Date: September 30, 2022, 6:07 am
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Very interesting, looking forward to reading your findings.
#Post#: 7668--------------------------------------------------
Re: CDI ignition
By: Ian F Date: September 30, 2022, 1:40 pm
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Looks good Jim and variable timing would certainly be an
improvement. I imagine it will need a power supply, crank sensor
and something to measure load such as a MAP or TPS sensor,
#Post#: 7669--------------------------------------------------
Re: CDI ignition
By: Jimr1999 Date: September 30, 2022, 2:24 pm
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From what I can gather, it needs a 12 volt supply and draws very
little current. , A 1 AH battery should last eight hours. It has
a sensor on the flywheel and a CDI unit to handle the
timing/advance depending on revs. This is attached to a coil
pack and the plug.
His Facebook page is not too descriptive as is the YouTube
channel. If it works out, I will post my results, if not I have
blown a hundred dollars and shipping. And we all know either
way.
Very few videos of the results yet from buyers on YouTube, as I
say, all new. He says I am the first Brit to have one... Watch
this space, it will be November before I get to it as I will be
away
#Post#: 7670--------------------------------------------------
Re: CDI ignition
By: Ian F Date: September 30, 2022, 2:44 pm
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So there's no load sensing then, I guess it will just be a
simple 2D rpm advance map. Not a bad price if it works as a
Megajolt or Nodiz is more than that, but they will support a 3D
map
#Post#: 7671--------------------------------------------------
Re: CDI ignition
By: Jimr1999 Date: September 30, 2022, 3:43 pm
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From what I can gather that's about it, as I say any solid
information is scarce, still, a 2D map beats no variable timing
for widening the power band and optimisation of the engine. It
is slightly better than a set of points and a vacuum advance
with the coil pack too😊... Time will tell
#Post#: 7863--------------------------------------------------
Re: CDI ignition
By: StefanN Date: November 4, 2022, 12:54 am
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This is an interesting experiment. Has it arrived? I’ve
always thought the torque on these engines is remarkably flat
and hence the power linear with RPM, within the narrow RPM band
they show. I’d be interested to see the results from a dyno
test of a stock engine across a wider RPM range - say 1000-6000.
#Post#: 7864--------------------------------------------------
Re: CDI ignition
By: Jimr1999 Date: November 4, 2022, 2:18 am
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Still waiting for it surface mail from Canada. I am almost
giving up hope! I have a house project that will take me up
until Xmas to fully finish at the moment Stefan so news on this
will be after that IF it arrives. (I will also post here when
(if) it does).
I do not have a dyno, but the system seems easy enough to mount
and swap so a direct comparison would probably be relatively
easy to do with the motor rigged to a bench. I can't imagine the
overall power being too much more with the way we utilise the
torque convertor as maxing it out rarely happens, I can see that
it *should* widen the torque available as the firing point
should be more optimal across a greater range if it is set up
well.
Watch this space.
Jim
#Post#: 7930--------------------------------------------------
Re: CDI ignition
By: Jimr1999 Date: November 25, 2022, 2:13 am
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Nearly two months down the line and still no sign of the kit.
Good job I am busy putting a posh porch on the back of the
hacienda.
Just read that surface mail from Canada can take up to 84 days!
(Phileas Fogg seemed to do more and quicker!) - and then it has
to clear customs in the U.K. (possibly up to 2 weeks) ... I
expect the huskys are on strike at the moment as well for
improved chow and better conditions ;)
... As always, watch this space.
Jim
#Post#: 8042--------------------------------------------------
Re: CDI ignition
By: Jimr1999 Date: January 10, 2023, 9:22 am
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Well, three and a half months in the post and the Canadian
surface mail has finally provided the goods. All I have to do is
make it work. I have a battery terminal for a 12V Milwaukee
battery of about 3AH, the only other ingredient needed is the
battery which should be here in a week or so. When the system is
live, it blows a small transistor in the original coil. If I
need to put it back to normal it is a £10 part.
As always, watch this space
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