Topic: Anyone running dyna ignition and dyna coils on their cb..?

[dergs713]

Finishing up my 75' cb550 build.  Are these really worth the money to convert to? Or should I just ride the good ol' points and aftermarket ignition coils.  New to this so anything would help, thanks!   

130 for the ignition..(point replacement)
130 for the new coils

Matt

[bollingball]

Are the coils you have bad? I still use points but many don't.
What is the ohm rating of the coils you are looking at?

Ken

[2manycbs]

I put them on mine 1975 550.  Coils have to be 3.0 ohm for the system.  They recommend resistance terminals on the plug caps also.  I got the whole system on ebay with wires for like 250 or so.  You can bump the plug gap up quite a bit, like to .040 per the dynatek specs.  I am very happy with them.  Set them once and you're done.  The ignition is stronger and you don't get any point bounce at higher rpm.  They have great tech support, you call and talk to a real person.  I would really recommend them if you need to replace your points anyway.

[crackerbat]

yep, runnin dyna + 3ohm coils on my 76 750f.. 1 less thing to monkey around with all the time.

[jcupit01]

Love my Dyna coils and wires on my 75 CB550k.  Got the 3ohm and kept the stock points, just retimed them.  Runs strong.

[Gordon]

You do not have to run 3ohm coils with a Dyna-S ignition.  You didn't specify which Dyna ignition you're talking about, though.  I run Dyna 5 ohm coils on my 750 with a Dyna-S, and stock Honda coils on my 550 with a Dyna-S. 

[madmtnmotors]

With the smaller bikes (and smaller charging systems) I'm pretty sure the 5 ohm coils (whether Dyna or OEM/stock) are recommended. I like to use the search at the upper right for better results. The search on the left ("Google custom search" under the header at the top left) seems more difficult to wade through the results. Anyway, there are some very good posts by Hondaman that lay down ignition recommendations for most models.

[KRONUS0100]

my 76 750F runs the green 3 ohm dyna coils and the dyna-s....with a resistor pack from Hondaman.  Bikes runs good and strong.  Dynatek has good customer service.

[WarwickE36]

Had 5ohm Dyna coils with Dyna-S ignition on my 74 550. Loved it.  Never gave me one bit of a problem.

[chickenman_26]

I put them on mine 1975 550.  Coils have to be 3.0 ohm for the system. 

The coils have to be a minimum of 3 ohms (more is okay) to prevent damage to the Dyna S system. I went with the 3-ohm coils but wish I'd gone with the 5-ohm for reduced current draw. I didn't realize at the time just how weak the CB500/550 charging system is. Now I have to use a 45-watt bulb in my halogen headlamp to reduce the drain on the battery at idle and slow speeds. If you're still using points, they'll last longer with the 5-ohm coils.


Stu

[Xnavylfr]

Just 1 question for my own knoledge!!

If you run DYNA S and you said minimum of 3 ohm coils and you ran 5 ohm wouldn't that put a load on the system and cause it to burn out?
In the same sense if you use 3 ohm with resistor plug caps aren't you adding to the total resistor of the system???


Xnavylfr(CHUCK)

[Eydugstr]

dergs713 - I run 5 ohm dyna coils and dyna on a CB750, no problems.  A lot of folks go to a 3 ohm coil and use Hondaman's resistor pack.  But seeing as your bike is a 550, what i'd recommend is one of Hondaman's transistorized ignitions (http://forums.sohc4.net/index.php?topic=67543.0).  Less power draw, less chance of frying a handlebar switch.

[heffay]

my dyna S failed... went back to points, all is right in the world again.

[vames]

1) Some people run stock points and like it.

2) Some people run stock points with Hondaman box and like it.

3) Some people run Dyna-S with stock coils and like it.

4) Some people run Dyna-S with Dyna 5-ohm coils and like it.

5) Some people run Dyna-S with 3-ohm coils and barely charge their battery.

6) Some people run Pamco with stock or Pamco coils and like it.

7) All of the above will make a SOHC4 run well and be very fun to drive.

8 ) Any of the above might fail at some time in the future or be complicated to set up, and those people won't like what they chose.

9 ) Lots of people on this board will get very nasty with each other, arguing for one over the other and feeling insulted if people don't validate their feelings.

[heffay]

8  ) Any of the above might fail at some time in the future or be complicated to set up, and those people won't like what they chose.

don't forget fail at the most inopportune time and strand you somewhere... at least points can be adjusted when they "fail", which is typically just "out of adjustment"

i'm gonna try hondaman's when i get the dough

[CycleRanger]

3) Some people run Dyna-S with stock coils and like it.

9 ) Lots of people on this board will get very nasty with each other, arguing for one over the other and feeling insulted if people don't validate their feelings.

Validate meeeee!  Please please validaaaaate meeeee!

Or else....

 

[vames]

don't forget fail at the most inopportune time and strand you somewhere... at least points can be adjusted when they "fail", which is typically just "out of adjustment"

i'm gonna try hondaman's when i get the dough

forgot.

7.5) Some people believe that every points failure can be fixed out on the road using chewing gum, a pocket knife, or whatever else is available.

[heffay]

not sure how "typically" is "every" ... I see what you did there

[BobbyR]

When all my cars had points we carried a spare set of points and condenser. The rubbing blocks would break off or condenser fail and fuse the points. Everything can work and everything can fail.

[Markcb750]

S**t happens, to everyone and everything.

When S**t does happen service is key to a good relationship.

Dyna Service sucks.

Just an observation.

[TwoTired]

Just 1 question for my own knoledge!!

If you run DYNA S and you said minimum of 3 ohm coils and you ran 5 ohm wouldn't that put a load on the system and cause it to burn out?
In the same sense if you use 3 ohm with resistor plug caps aren't you adding to the total resistor of the system???

That's actually two questions...   

The 3 and 5 ohms refers to the primary resistance of the coils.  To make a higher output, the coils can be wound with a different turns ratio.  Less turns on the primary increase the ratio and can provide a higher output voltage given the same input voltage.  Less windings equates to lower resistance as the length of wire used in the coil is shorter.

The primary is what is switched on and off by points or the dyna.  A lower ohm resistance increases the load on the switch (and the power supply/system, via ohms law.  I = V/R ; Where I is the current (amps), V is the Voltage and R is the resistance in a DC circuit.  If we make V a constant, plugging in different values of R (3 and 5)  Will show just how much increased current will flow in the circuit . 12/3 = 4 Amps  and 12/5 = 2.4 Amps (only when the switch  or contact points are closed, of course).

I suspect you have the concept of resistance backwards.  Zero Ohms is a direct short.  Where high ohms or infinity is accepted as a very low (infinitesimal) current flow.


The plug caps serve a totally different function.  But, while the spark channel is active, the resistors reduce the peak current and elongate the spark event through conservation of energy.  Without the resistors little restraint of the spark current occurs, the event is intense but over in a very very short period of time.    With resistors, the event occurs at the same voltage, but the current drain is slowed by the resistance to flow and the event duration is extended.

 AC circuits have different and more complex behavior than DC circuits.  And, coils clearly operate in the AC domain by virtue of the switched input and pulsed output operation.  Training for AC circuits comes after training of DC circuits in any teaching curriculum I'm familiar with.

Cheers,

[dergs713]

Wow A lot to choose from I see.  I really appreciate it all guys, I "was" just going to pick up the dyna coils from LOWRIDERS BY SUMMERS.  Guy seems very knowledgeable.  It dosnt state whether they are 5 ohms or 3 though.... and the Ignition Pack is the Dyna S.

 The bike is goin to be my main mode of transportation 50+miles a day.  (Trying to stay away from my 11mpg wrangler, with gas being 4.50 in chicago...) Im hoping it will be all good, if I put everything together right.  I also need to extend the spark plug wires due to the coils being places under my seat. 

Remember the bike is being stripped down. Just brake lights headlight etc.. blinkers later..

Should I go with a 5ohm or a 3ohm..?  also Can I do one before the other without frying anything...?

Thanks to all!

Matt

[dergs713]

Also are they the same for 750's and 550's. Im new to the Bike world. 

Bike again is a 1975 cb550four

Matt

[Eydugstr]

I'd play it safe and stick with the 5 ohm coil.

[CoachDoc]

I'd play it safe and stick with the 5 ohm coil.

Agreed. Read Hondaman on ignition systems to become enlightened, and for a 550 stick with a 5 ohm coil set.