The verdict: Dyna , HEI mod, or stock ignition

So I have a 79 KZ750 and wanting to change out the points to electronic ignition. I have read several posts in regards to using Lou's HEI mod ( home.comcast.net/~loudgpz/GPZweb/Ignitio...heiModForPoints.html ) but, they seem to be very old posts. Since it's 2011 and technology has evolved. Is the HEI mod still the preferred method over all other options. I can buy the Dyna S 2-2 for about $130 which isn't bad, but compared to the HEI mod at $30 total, trying to find the value in the extra $100. I would also like to know if anyone is using the Dyna electronic ignition...how is it at idle? I have read that it sucks the life out of the charging system but, then again, old post-old dyna system. Basically I would like some "up to date" info.

Thanks Guys

Dyna is a good replacement for points. It would be the next step. As far as the progression would stand in ignition quality/technology it would be in this ascending order. 1-points, 2-Dyna, 3-OE Kawasaki electronic ignition, 4-Lou's HEI GM ignition. There are other ignitions that would be better but they are in the multiple hundreds of $.

otakar wrote: Dyna is a good replacement for points. It would be the next step. As far as the progression would stand in ignition quality/technology it would be in this ascending order. 1-points, 2-Dyna, 3-OE Kawasaki electronic ignition, 4-Lou's HEI GM ignition. There are other ignitions that would be better but they are in the multiple hundreds of $.

I'm curious as to why OE is better than dyna? Not at all trying to say it that it isn't, I have OE on one of my bikes and was going to swap for the dyna off my wrecked bike when I read that OE was better somewhere on this site. (glad I decided to look it up) I have wondered what the difference was though and when I saw your post i thought maybe you could shed some light on the subject otakar.

I will give you my opinion. The Dyna requires more power. A Dyna doesn't like power spikes very much.

A bad regulator can fry a Dyna.

I have been running Dyna for 12 years. No complaints.

Dyna is a lot easier to find than stock unit.Roy

As far as why OEM is better than Dyna, do a search on KZR and see how many have Dyna S ignition systems and have lost one side (two cylinders).

I don't know anyone that has put a Dyna S on a 750 twin, and don't know how well it would work.

Most people use the electronic ignition off the KZ440 or 82-83 KZ750 twins to convert.
I've used both with no problems.

The OP doesn't specifically ID it as a 750 twin, but the only 79 750 is a twin.

Then you have this company in England, making a CDI for the Z1000's:
www.electrexworld.co.uk/stk-310-stator-kit-11356-0.html

Sorry, my bike is a 750 twin. Any thoughts on the HEI mod? Seems cheap and easy to make.

oldschoolbobber wrote: Sorry, my bike is a 750 twin. Any thoughts on the HEI mod? Seems cheap and easy to make.

Like I can't spot a 750 twin quarter mile away :laugh:

There's two ways of using the HEI module, one is build a igniter using the stock electronic ignition advancer and pickup, the other way is to use it in a transistorized ignition with points.

Like I said in an earlier post, most people use 81 and new KZ440, or 82-83 KZ750 twin, electronic ignitions to convert the 76-80 750 twins to electronic ignition.

The HEI stuff was designed and published by our very own Loudhvx, a genius with electrons.

I have the electronic ignition advancer and pickup out of a 440 if you decide to go that way.

Here's my 79 750 twin, slightly modified

vcd,a proxy perhaps. :huh:

nice bike steel,

leon

Steell, very nice bike. Looks to be in great shape! I'm guessing with the tank bag..you've put some miles on her? I always get distracted for some reason when I read your posts. I wonder if it's the avatar, lol?!? I have the parts to do the HEI mod using the points. Probably would just do the "basic" setup since I don't have a lot of room to hide things. I have found a stock Kawi electronic ignition off an 82' pretty cheap. Correct me if I'm wrong...82' was a 4 cylinder only? Which direction would you go...HEI...stock elec. ign.? Anyway, here's a pic of my bike:

82 KZ750M is a 750 twin, 82 KZ750H, KZ750E, and a couple others as well, are fours.

Sweet bike! If that was mine, I'd ditch the battery and go kick only.

There are several benefits to the Kawasaki electronic ignition over the Dyna S.

First is reliability. The Dyna S mounts it's electronics on the engine near the crankshaft. Heat and vibration are not friendly to electronics. The Kaw system mounts the electronics in a box on the frame.

Second, is efficiency. The Dyna S uses a very long, fixed dwell angle. This means at lower RPMs, the coils are getting full-current for way longer than they need to, and none of the extra current corresponds to any extra spark energy. All of the excess is just wasted as heat in the coils. As a side effect, this extra heat actually increases the coil's DC resistance slightly which actually reduces the current slightly and results in slightly less spark energy. The Kaw system varies the dwell angle using the natural effect of variable reluctors. Very clever. This means it saves power at lower RPMs and still has good dwell at higher RPMs (when the correct coils are used).

Third, the Dyna S system uses power anytime the ignition switch is on. With the factory electronic system, there is no coil current until the crankshaft is actually turning. People have cooked coils by leaving the ignition switch on, accidently, with the Dyna S.

However, as Otto said, the Dyna S is still a very good system and may even be cheaper than converting a points system to the factory electronic ignition, when all is said and done. The Dyna S can use the points coils, so if the points coils are good, there is some cost savings there. (The factory electronic system would require different coils than a points system.)

Dyna also has a very good history of replacing defective units.

The HEI module is just a replacement for the factory module in the factory system. It works basically the same, but the dwell variance is increased a little more to make it more efficient. It is also less susceptible to crosstalk between pickups that the factory system sufferes from slightly (it is noticed as little pops or puffs at idle, not really a factor to worry about).

Since you are on a twin, for which there is no offered Dyna S system, you would have to cobble one out from a 4-cylinder version. As Steell said, you can use the pickups and rotor from a 440 or later 750 twin, to make a factory system. This is what I would do. The extra efficiency is what makes it possible to ditch the battery.

The crank on a 4-cylinder bike turns the opposite way, so you can't use the advancer/rotor from a 4-cyl bike. The Pickup plate appears different too, but functions the same electrically.

The points coil will not work well for the factory electronic ignition, so you'd need one of those too. The dyna gray 2.2 ohm coil is what you'd want if you are buying new.

If you are just using the points to trigger the HEI system, then make sure the points are clean. Pitting and/or dirt introduces randomness into the dwell and timing.