Cheap CDI

That style of CDI is not compatible with the HT system.

It is part of a typical 3 piece motorcycle system:

1. Stator with trigger coil.
2. CDI box.
3. Ignition coil.

HT engines do not have a trigger coil.

The trigger coil would send it's signal to pin #2 on the diagram that you shared with us.
 
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Ok great. This is the kind of response I need. I know the ignition coil will work, but I bought the CDI on an impulse because of the price. It was half the price of a replacement stock CDI, so how could I pass it up? Now that being said, I would like to set up a better ignition system with timing advance and retard curves, etc. that will also smooth out the vibrations at high RPMs (Basically emulating/replicating Jaguar's system) because I'm getting shook apart at WOT. I would like to run at my top speed without fear of losing every nut and bolt on my bike. Is there a reliable (read "cheap") CDI that will work with our engines and the CR80 ignition coil that doesn't cost $75 for minor performance gains? Can this CDI I have in this thread be modified in a way that could work with the HT engines? I think research and development is key, and I very much appreciate the continued input. Help me guys!
 
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I've read that it's best to mount the engine as solidly to the frame as possible. I slid a piece of innertube between the mounts and the frame. If this is causing the vibration, I'll remove them. It was said that if using rubber mounts, the studs can break. When I go to full throttle, I get a severe "buzzing" vibration in the handle bars to a point where I have to let off the throttle. I'm wondering if it could be another factor like the vibrations of the headlight and battery box assemblies. The upgraded CDI/coil combo is said to alleviate these vibrations at high RPMs. That is/was my goal for this whole project. I guess maybe I'll just have to live with cruising at 27mph when I know I can go, and have been, over 30mph. It just seems like something is going to "buzz" apart or the engine is going to explode when I get up to top speed. I know I'm new to this, but there has got to be some kind of happy medium for this "chinese super bicycle happy time" engine.
 
Thanks. I've seen that thread before, but haven't looked at it in a few days. I see Rohmel has made a few. I'm really interested in trying one out.
 
The tricky part is the flywheel on a motorcycle has a separate magnet for the trigger coil, offset from the magnets that excite the alternator coils.
The trigger magnet position is precision timed to the crankshaft.

Usually the alternator magnets are on the inside diameter of the flywheel and the trigger magnet is on the outside of the flywheel. All coils involved are positioned respectively to the magnet positions.
 
Thank you. I checked the tracking stats and should be receiving both the ignition coil and cdi module today. I will try this set up first, post my results, and then attempt to make one of your cdi's.
 
Sorry, I was out of town all weekend. I received both the ignition coil and CID unit, but I haven't had a chance to connect it. I'll try to wire it up tonight, but I probably won't get an opportunity to fire it up until tomorrow (very quiet neighborhood at night). If it doesn't work, I'll trash it (CDI) and build my own.
 
Good idea. But it looks to be filled with the same black epoxy as the stock CDI. Maybe I can chisel it out... but first I'll see if it works, of course.
 
UPDATE:
Bad news. While removing the plastic plug casing to expose more of the pins to solder jumpers to, I accidentally snapped off a pin. Since the whole thing is filled with epoxy, it's impossible to even dig it away to expose enough of the pin to solder to. This might be a good sign to follow more experienced people's work on these...
 
Do you have a dremel tool so you can grind away at enough of the epoxy so you can solder a lead onto what was running to the pin?

Good luck
rc
 
I tried that. Then I started nipping away at the case itself and found nothing. It was a lost cause and a waste of $6 on my part. I couldn't find the wiring harness I needed as soon as I wanted it and rushed things. I hate ruining things that could have been something. Oh well, c'est la vie...
 
I don't have any of that lying around unfortunately. Maybe I'll keep chipping and gnawing away at it until I find something recognizable. I'll definitely have to excavate the components.
 
Ok. Round 2. I decided to give it another try before I build my own CDI. I bought a cheap racing CDI that looks almost identical to the JN Motors unit. How do I hook this up? I'll be using a CR80 iginition coil with it as well. It has 5 wires which are all red and black...Any help?
 

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Ok thanks. So the orange and black go to the positive and negative (respectively)on the coil, the black wire on the left in the pic is ground? and the other 2 go to the black and blue wires from the engine? Obviously I'm guessing here...
 
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