This is a review of the Dyna ignition for the '94 and later Honda Magna. I purchased and installed mine in August '03 for my '99 Magna.
Overview
The Dyna ignition for the Magna is Dyna part # D3K1-5. It is available from many on-line motorcycle parts suppliers. I purchased mine for $265 including tax & shipping from Metro Custom Cruisers. It consists of a small aluminum box that replaces the stock ignition control module (ICM). Dave Dodge did the dyno curve testing for this unit.
Installation
Installation is straight forward. You unplug and remove the ICM, and install and plug in the Dyna. Then you set the two knobs on the Dyna to select which advance curve and your rev limit. This simple install should take 10 minutes but it actually took me 45 minutes. That's because the Dyna is a little bigger than the stock ICM, which was a tight fit to begin with. On top of this, one must partially remove the battery box to perform the install, and the bolts for the battery box are hard to reach. Overall it's quite easy, just a little tedious. The end result, however, is a neat and perfect fit.
First Impressions
The fit and finish is excellent, better than stock. It comes in an anodized aluminum case (the stock unit is plastic). It has two knobs, one for the rev limit, the other for the advance curve. It is trivially easy to set up. It worked perfectly the very first time.
Tuning
You have to know a little about bikes to know which advance curve is best. Stock bikes have lean carburetion which will ping if advanced so there is not much benefit to the Dyna. However, it does have 3 timing curves to support this configuration. Bikes with jet+shim kits with aftermarket exhaust can take a little more timing advance, and can keep making power to slightly higher RPM, so Dyna can provide improved power and torque. Curve #4 is best for these bikes. This curve has a little more advance from 1500 to 4000 RPM, and holds full timing from 9000 RPM to redline (the stock ICM pulls 5* of timing from 9000 on up; the Dyna does not). Thus it provides a little more low end torque and a boost to top end power than you can feel in the seat of your pants. Curves 5-10 are for bikes with more extensive mods (cams, compression, etc.).
On top of the benefits of the advance curve, the Dyna puts out a bigger, fatter pulse to the coil. This should eliminate intermittent misfires, especially at high RPM.
Redline can be set anywhere from 9500 to 12000 RPM in 500 RPM increments.
I find a good rev limit is 11000 RPM; for max acceleration I shift when the tach reads 11000 which is actually about 10500 RPM. The stock valves begin to float around 10500 RPM. But since the stock ICM pulls 5* of timing at 9000, the Dyna gives extra top end power from 9000 to 10500. This does not seem like much on paper, but it really makes a difference. Plus the slightly higher redline enables you to run 15/40 gearing without sacrificing speed in gears. You can actually run up to 15/43 gearing to really take advantage of the higher redline and the stock chain will still fit with 15/43 sprockets.
NOTE: As mentioned above, the Dyna doesn't do much unless the bike already has jetted carbs. Aftermarket exhaust is also a plus as the improved flow helps the engine breathe at the higher revs.
Caveats
The Dyna made my tach read about 500 RPM higher. Strangely, the error is not a percentage, but a constant 500 RPM throughout the tach range. For example, if you set the rev limit to 10000 RPM, when it kicks in the tach will be reading 10500 RPM. This is annoying but in my opinion is just a reminder that the Dyna is putting out a bigger, fatter pulse to the coil.
One more item worthy of mention is that the Dyna makes cold starts a little touchy. You have to get the choke just right for a cold start else the engine will die. On cold starts with the Dyna, the bike likes to be lean for the initial catch but immediately after the catch it wants a richer mixture. This is not a big deal... just something to keep in mind.
The Final Word
If your bike already has jetted carbs & aftermarket exhaust,
the Dyna ignition is a good mod for improved torque & power.
It is a true bolt-on mod that is easy to perform.
I switched to 15/40 gearing to take advantage of the higher redline.
The improvement to low end torque is slight, hard to feel.
The improvement to top end power is enough to notice.
Overall, it's a good mod if you don't mind the tach issue (and I don't).