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Discussion Starter #1
I notice on most cam trigger CDI setups (atc, xr200, etc) there tends to be a magnet on the trigger. Whereas on most crank setups there tends to be just a square edged protrusion on the flywheel. Is this due to advances in technology or is the cam not spinning fast enough at starting for an internally magnetized hall effect sensor to generate the required trigger voltage from a simple protrusion on the trigger?

Building the items to put a crank trigger pickup onto say a sideport xl engine in the stock point location shouldn't be too hard. With a CDI that has an internal advance curve, the trigger could be nothing more than a sleeve with the protrusion milled into it. No mechanical advance needed. But if I required a magnet it becomes a slightly more challenging build. Not the end of the world though as I can now build the sleeve from aluminum and epoxy the magnet in place. (I also realize some stator work is in order for the XL mentioned above)

Thoughts? I am considering the fabrication of a small test setup to try this using a DC cdi box (because I can power it from a bench supply) and different pickups.
 

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Not sure what mag these came out of but this should be a good start. I was going to try out a hall effects setup on the CL175 just for kicks.
The 5 volt pulse is perfect for rouiting to programable chip for ignition curve, I think this is designed for 3 to 5 ohm coils, more research on that might be needed. Hall sensor is the mag type and 4 point star is reluctor.

Programmable Ignition System For Cars article:

http://www.vespalabs.org/@api/deki/files/479/=kc5442_Programmable_High_Energy_Ignition_System.pdf
 

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Look at the thing for sale on mikesxs it is very simple and uses magnets set in a simple flywheel with nothing to stop vibration from destroying components over time like a little silicone or epoxy. it is just a trigger though, electronics not wheel. All the parts for this would be very cheep. I think if I look I have a diagram for building this type of trigger somewhere but the type I had was to be set in epoxy for protection from vibration.

 

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Discussion Starter #5

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Rotating magnet like a DYNA makes sparks at zero rpm. Rotating reluctor (machined slab of metal) needs more revs to trigger and harder to statically time.

We used a couple of Suzuki systems but needed to crank teh motor to see if it sparked. Changed to a dyna and problem solved. No doubt there are better static timing systems, but for my apps ( simple race bikes - Honda CB77/160/175 , GT750 Suzook etc) Dyna is simple and effective, but no advance curve on a DYNA S.. You could slide a DYNA S rotor over your mechanical advance/retard and it one module from a GL1000 system which drop straigh in to a CB175/160/200 and may fit yours.

Or go with something like an Ignitech fully programmable with magnetic pick up and machined reluctor - as long as you can work out if the leading or trailing edge triggers it.
 

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Discussion Starter #7
quote:Originally posted by Teazer

Rotating magnet like a DYNA makes sparks at zero rpm. Rotating reluctor (machined slab of metal) needs more revs to trigger and harder to statically time.
This was precisely what I expected. Kicking a rotating reluctor to life would be pretty much impossible. A flying magnet setup shouldn't be too hard to machine up.

I have used the ignitech products before. I really like those.

This setup is for a few old thumpers that me and my dad own.

Edit: I consistently typo magnet.
 

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I was informed that the circuits were in connection with a write up on this product. Looks interesting.

http://www.jaycar.com.au/productView.asp?ID=KC5442

Programmable High Energy Ignition System

Refer Silicon Chip
This is Silicon Chip's most advanced and versatile ignition system yet and can be used on both two & four stroke engines. The system can be used simply to intercept and modify the factory ignition timing or turned into a stand alone ignition system with remapped timing, electronic coil control and anti-knock sensing. The unit will trigger from a range of sources including points, Hall effect sensors, optical sensors, or the 5 volt signal from the car's ECU. Timing can be mapped against engine load and RPM and adjusted in step as small as 0.5°. Requires KC5386 and WC7502 with all pins connected.

Features:
> Timing retard & advance over a wide range
> Suitable for single coil systems
> Dwell adjustment
> Single or dual mapping ranges
> Two de-bounce settings
> Max & min RPM adjustment
> Suits 1 to 12 cylinder four stroke engines and 1 to 6 cylinder two stroke engines
> Optional knock sensing & correction
 

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Discussion Starter #9
Yeah. I could probably bang out a programmable setup on a cortex M0 or something in a few hours.

That link looks like a good bang for the buck if shipping didn't kill me.

On an unrelated note....isn't someone making a piezo injector that doesn't require
 

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Just replaced photos with PDF of the 3 articles about the unit I did not read but think it may contain all the info to build the units + mobile programmer.
 

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Discussion Starter #11
sweet. thanks for the pdf link.
 
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