Topic: CB500/550/350F/400F Ignition 'hopup' kit: how much interest?

[HondaMan]

The alternator-challenged smaller SOHC4 bikes CB350F/400F/500F/550F always struggle with low-battery issues when spark 'hop-up' stuff is attempted. I get LOTS of e-mail about the resulting problems, and those of you who have sent them know I pretty much answer the same way in most cases.

So...if I created a "kit" that would improve the spark without enslaving these alternators, where you could get the whole shebang in one box, would there be much interest? This 'kit' would consist of the following, if I can find the parts for a reasonable cost:

1. Hondaman Ignition module.
2. Dyna 3-ohm coils with copper-core spark wires.
3. Resistor Pack, 2-ohm value.
4. 10,000 ohm NGK plug caps, set of 4 (kinda hard to find...).
5. ND sparkplugs of the correct heat range for the bike.

This package would create the following specs:

Spark voltage of approximately 9700 volts (OEM is 7500 volts).
Spark duration of 1.25mS (OEM is 1.45mS).
Current draw of 2.50 amps (OEM is 2.6 amps).

The advantages are:
1. You would use a sparkplug gap of 0.030" to 0.032" (OEM is 0.024"-0.028"), resulting in a larger flamefront.
2. The coil's spark wires are replaceable.
3. This 'system' uses less power than even Honda's OEM setup.
4. This 'system' provides 25% more spark voltage and 20% more spark energy (mostly used for 'bragging rights' with your friends...).
5. The points last a VERY long time (and provide 100% backup if the Module fails), greatly reducing tuneup intervals.
6. Cold-bloodedness (on the post-1974 bikes) is greatly reduced.

Of course, you can use these same components yourself and get the same results (I will offer the 2.0 ohm Resistor Packs on my website shortly), the only advantage being possibly the one-box-fits-it approach.

It won't be cheap! The coils are expensive, for starters. I am considering a "group buy" from Dyna or ACCEL (if they will do it) if there might be enough interest? Right now, I don't know how much 'interest' might be in numbers, but will investigate after I see some feedback here for a while.

[Gman]

HMan,
I'd be interested.  I was planning on getting your ignition at some point anyway, so might as well upgrade the whole kit 'n caboodle at once.  I understand the difficulty of pinpointing an exact price due to trying to buy different components from different places, etc. but do you have a ballpark of what 'expensive' is?

Thanks, as always, for all you do for the community.

Cheers,
G

[Stilltime]

HM,

I may be interested as well.  About to tackle adjusting my ignition for the first time, and have considered an electronic ignition or possibly adding your transistorized units. 

Thanks,

Chris C.

[2ceebees]

Yep, count me in for more info as well.  Need to do a complete ignition system so this sounds like a good idea. 

[bbullitt]

I would be interested.  Would the kit work with 5ohm coils?  I just bought these coils, so I would need a kit without.  Or would the kit be pointless with the different ohm coil set up?

[bjbuchanan]

I would be interested.  Would the kit work with 5ohm coils?  I just bought these coils, so I would need a kit without.  Or would the kit be pointless with the different ohm coil set up?

You wouldn't need the coils or ballast resistor. You would just be getting fresh points wires plugs and his ignition. It would be like 120$ extra for no reason in your case because of having the coils

[Steve_K]

Count me in for a 550 kit.   Having a good ignition makes carbs work better!  Would the Dyna coils fit in the stock coil location?
Steve

[Doggie]

Count me in too. Like to update the next CB550F that i'm building to all the modern stuff.
                                              Doug

[Deltarider]

3. Resistor Pack, 2-ohm value.

Hondaman, I would suggest 1,5 Ω maximum for that resistor pack. The stock coils I still have always read 4,7 Ω on all 4 DMM's I have. Furthermore my bike (and wiring!) is 37 years old and between the thick battery + cableterminal and the coils I read 1,5 Ω already!
BTW, a question I asked before (and had no answer too): is the 1,5 Ω impedance in my (old) wiring and connectors as good as a resistor or do I miss something?

[HondaMan]

3. Resistor Pack, 2-ohm value.

Hondaman, I would suggest 1,5 Ω maximum for that resistor pack. The stock coils I still have always read 4,7 Ω on all 4 DMM's I have. Furthermore my bike (and wiring!) is 37 years old and between the thick battery + cableterminal and the coils I read 1,5 Ω already!
BTW, a question I asked before (and had no answer too): is the 1,5 Ω impedance in my (old) wiring and connectors as good as a resistor or do I miss something?

The main difference between the 1.5 ohms you are seeing in your bullet connectors and the 1.5 ohms of a (well-connected) Resistor Pack is: the connectors themselves exhibit a higher resistance under heavy current load than what you are measuring with a milliamp ohmmeter. The ohmmeter does not pass enough current to heat those connectors, and when they are running 'hot' they often drop even more voltage. This is why we see so many 500/550/400F/350F bikes with 9.5 volts at the coils. If the connectors are polished or renewed, and the Run/Off switch is cleaned up, this voltage can rise to almost 11.2 volts (from a 12.8 volt battery), which makes for a much happier bike. This makes possible the control of the 3-ohm coils within the bike's power budget: if we can get along with less spark voltage (but still more than OEM) and make enough spark duration in the process, it works out better overall.

There's actually several reasons to use the 2 ohms with the 3.0 ohm coils on these Mid-Fours. One of the reasons is to reduce the current to something these bikes can manage, but the other is to extend the spark duration by slowing the primary discharge rate, so as to dampen the magnetic breakdown rate of the spark coil side. The Dyna coils have short discharge sparks (to find a very wide array of bikes in a general form), but the OEM coils had very long ones. Slowing the magnetic field collapse also extends the discharge time. It reduces the spark voltage a little, but anything more than a solid 7500 volts is wasted unless the plug gap is also opened or the compression ratio is changed upward. The 3-ohm coils make 25kV at 12.8v unrestricted feed into a .045" gap plug, but the geometry of the chamber only benefits (on these smaller bikes) from a gap up to .035" because that is the depth of the "rich" layer of the stratified charge they make. Hence the approach...

These stratified-charge engines are designed to appreciate the extra burn flamefront that is created by the longer discharge (ESPECIALLY the 750 and the 350F), particularly above 5000 RPM where most of them operate.

I've long wanted to make a 'kit' like this, and have installed these bits and pieces in a haphazard way on some of these bikes. But, I think a comprehensive package would help a lot of folks out? And of course, it provides a way to allow for spark wire changes.

[kghost]

Cool stuff mark. I already have the ignition on my 400.

Might need one someday for the 350

[Brandedone88]

I am extremely interested as I have had starting problems relating to the poor spark,etc.  If it can be had at a reasonable price, you can make a good profit.

[Kurt V]

My 400F runs very well on the stock ignition. Would I see any improvement using your proposed kit?

[alacrity]

I love the ignition kit I got from you that is on my 72cb500k1. I sourced all the other stuff elsewhere (dyna coils, etc). 

I'd be interested in the timesaver / all in one kit for the 77 cb550k that is my next project.  Thanks.

[Tews19]

I may be interested depending on the overall cost. I will continue to follow this thread.

Sent from my SAMSUNG-SGH-I337 using Tapatalk 2

[jason41987]

heres my question.. you already have all the components available, really all youre doing is selling them all as a group for the kit, since youre really not making anything new and the individual components would sell anyway... my question is why NOT offer a kit to those who need it all?.. makes sense, and if i didnt already have about half those components already, id probably have purchased it too

[Lostboy Steve]

Let's talk cost. I am fine with my stock ignition but I guess it couldn't hurt performance having a hotter burn. I liek that you keep the points.

[englishwheeler]

I would be interested too. My customer wants to update the ignition system on my bike he bought from me. Let me know when you get the kit squared away.

[HondaMan]

heres my question.. you already have all the components available, really all youre doing is selling them all as a group for the kit, since youre really not making anything new and the individual components would sell anyway... my question is why NOT offer a kit to those who need it all?.. makes sense, and if i didnt already have about half those components already, id probably have purchased it too

Well, what I have now is just the 1.0 ohm Resistor Pack for the 3.0 ohm coils for the 750 (which some have also used on the 500/550), and the Transistor Ignition. The situation is: I get about 4-8 e-mails for every Resistor Pack I make because I have to explain why the other parts are also needed, and have to ask about their coils, plug caps, and whether they have a Dyna. Boyer, or whatever ignition already. I end up with so much e-mail that I often have a hard time keeping up with it. After all that is done, the ones with the 500/550 bikes still end up with marginal charging systems (especially if the headlight is a hi-wattage halogen). So, I am hoping to improve on the overall situation, in a single package?

I'd even consider having an H4 headlight with the 35w/35w bulb in a version of the kit. This would actually IMPROVE the charging systems for a change, and it could then be extended to the 350F/400F bikes, too.

It's going to boil down to the cost of those [expensive] Dyna coils, in the end.

[Steve_K]

An H4 bulb included with the kit would make it a very good buy for me.

Gee, all I would need now are the GOOD points for my project.  Have you a source for those, Mark?

I have the ignition and your fuse blocks on my 750 and they work very well. 

I can't wait to up grade my 550.

Steve

[InTheStreet]

I might be interested in about a year.  My two concerns are the availability of the spark plug caps (what happens when I need new ones down the road?) and the cost of the system. 

[Sparked]

I would be interested as well for my 350f. I've patched the coil wires too many times as it is, and was looking in getting the HM ignition soon anyways.

[jason41987]

specifically which dyna coils are you referring to?.. im actually in need of a set of replacement coils.. was thinking of picking up new coils of yet to be determined resistance, 3ohm with resistor pack or 5ohm, and was planning to add the hondaman ignition module later... i think my caps are 5k though... wonder if the internal resistors could be swapped out?

what id really want to know though is an estimated price for such a kit?

[SF]

Im in! I need to replace every thing for my 550 project. I think this would save me alot of time. would this kit be good with a big boar kit?

[jason41987]

i already have the 3ohm dyna coils... how much for the suggested 2ohm resistor pack?