Electrical problem

[SIKPUPY]

Wonder if anyone out there can help.


If I use the Earth to the CDI can I use it as a switching point without any adverse effects on the CDI?

Any info will be appreciated.

[Desmo]

A switching point?

[SIKPUPY]

As in to turn the bike on and off, without stuffing around with the ignition switch, kind of like an immobilizer but not really.

[Desmo]

It's generally bad practice to use an earth to control power to a unit.
I wouldn't.
Why not just cut a switch into the ignition wire?

[SIKPUPY]

It's generally bad practice to use an earth to control power to a unit.
I wouldn't.
Why not just cut a switch into the ignition wire?

I cant seem to work out the positive feed to the CDI otherwise I would use it.

I thought about using the feed to the coil but the other problem with that is the Coil runs off the CDI, am I going to be able to run a small relay off the feed to the coil without killing it?

[Desmo]

Just kill the coil +ve, should only be 12V.
I'm sure there are better ways though, like finding the +ve for the CDI.

[Nero Diablo]

I cant seem to work out the positive feed to the CDI otherwise I would use it.

I thought about using the feed to the coil but the other problem with that is the Coil runs off the CDI, am I going to be able to run a small relay off the feed to the coil without killing it?

A CDI generates its own power through its own windings in the cases generally a CDI is cut off buy shorting the unit to earth (this is what the ignition switch does). So breaking the connection to earth would actually stop the ignition switch from turning off the motor. The obious question why is the ignition switch is such a problem?

[SIKPUPY]

I didn't want to pull the whole bike apart to get to the ignition switch and wiring tonight as I kind of need all 3 of my learner bikes on the road in the morning. Was just an idea I had.

I sort of understand how a CDI works but I thought that it would of had a positive feed, looks like I was wrong. From what I can work out there is AC CDI's and a 12V DC CDI. I could do what I want to by shorting the CDI to earth but I was also trying to prevent it from turning over at the same time by using a relay to cut the starter feed as well.

I will just have to pull the front half of the bike apart when it is daylight and I have a few more hours to nut it out.

Thanks for the help.

[Nero Diablo]

I didn't want to pull the whole bike apart to get to the ignition switch and wiring tonight as I kind of need all 3 of my learner bikes on the road in the morning. Was just an idea I had.

I sort of understand how a CDI works but I thought that it would of had a positive feed, looks like I was wrong. From what I can work out there is AC CDI's and a 12V DC CDI. I could do what I want to by shorting the CDI to earth but I was also trying to prevent it from turning over at the same time by using a relay to cut the starter feed as well.

I will just have to pull the front half of the bike apart when it is daylight and I have a few more hours to nut it out.

Thanks for the help.

Not sure exactly what you are trying to do the CDI unit will only work if the motor turns ie it is independent of the battery so if you simply stop the starter feed the motor will not start unless someone bump starts it or kicks it if this is an option. If however you want to stop the motor then you need to short the CDI or coil (if it has one independent of the CDI) to earth to remove the ignition source otherwise the motor will continue to run until it runs out of fuel.

[darkfibre]

What sort of bike are we talking about. A lot of bikes stopped using CDI during the 80s although many people still call it CDI.
Generally CDI will pulse positive to the coil and ground one side of the coil. Later Electronic ignition (TCI) Supply power to the coil and switch the negative for spark.

Without knowing exactly what system you are dealing with, some of the above advice may not apply to you.

[SIKPUPY]

Its a Kymco.. They have new technology called CDI's. Beats having points and a dizzy They even have kick starts on them but I took them off.

I have nutted out what I am going to do but won't be getting back to it for a couple of weeks now.

Going to use a switch to earth the CDI so that the bike wont run, which I can use the same switch (DPDT)earth to shut off a small relay that will cut the feed to the starter motor relay. Means I can permanantly disable the bike and should be able to do it on call depending on the wireless remotes that I find.

[Desmo]

Its a Kymco..

kind of like an immobilizer but not really.

I don't think you really need to worry.....

[darkfibre]

CDI is not new technology.
I don't know where points came into the conversation.

Personally I don't like grounding a circuit that I don't understand the workings of.
For instance on my little FZR I know for a FACT that if I ground either side of the coil it WILL cause problems.

Can you source a wiring diagram? Then a definite answer can be given.

[filbert]

it's a cool idea if you immobilise a bike at random by remote you can prepare the rider for ducati or harley ownership, a useful service for a riding school -)

[SIKPUPY]

it's a cool idea if you immobilise a bike at random by remote you can prepare the rider for ducati or harley ownership, a useful service for a riding school -)

Hehe

Never thought of that, was just for an idea that I am toying with.

[HK31A]

most circuits are completed when grounded

[SP33D]

most circuits are completed when grounded

Thanks for the tip