Coil Mod for bikes without points...will it work??

Coil Mod for bikes WITHOUT points

Will it work on my 1984 vf700??

 

it should, all your really doing is replacing the old wiring to the coils with a new circuit, im not sure you'd see all that much of a benefit, but hey the wiring is 25 years old, im sure it has more resistance than fresh wire
on my 83 1100F supersport, using coils from a cbr was an easy swap and def. throws a much higher voltage spark now. i just scored a set of f3 coils/wires that should perk up my 85 700

 

.............and the advantage gained with this trick is WHAT ??

 

less resistance to the coils = more power to the plug i guess.
putting cbr coils on my 11f was just a low buck upgrade to get a dyna/accel level of spark...and molded plug ends

 

The mod will work as it takes out of the game the voltage drops in various places from wires, contacts and switches. You can measure the voltage at the coils before modding then run a cable from battery to the coil and measure again. I reckon the voltage difference will be more than 0.5 volts which makes the mod worth the effort.
Advantages are higher primary voltage in coil resulting in higher secondary high tension voltage.
Better spark especially in starting.

 

my thoughts exactly which seems to make it a no brainer on a 26yr old bike...thanks for the input

 

How do i know if i need bigger sparks ?? My bike runs too strong already .

 

You can check the spark length. As a rule of thumb it should be more than 15 mm on air pressure.
You don't have to do a thing if your bike runs fine and you are happy with it; as a matter of fact the gain would be minimal with bikes that don't experience ignition problems.
On the other hand there are people that change the standard plugs with special type in order to improve fuel burning. Those would probably benefit from the mod.

 

I spoke with an old hot rodder friend of mine and this is how he summed it up...a hotter spark, in turn burning the fuel better and getting better combustion and better gas mileage and a little more power and less emissions.

 

That's assuming the bike has enough compression and/or not enough spark already

 

You could probably get the same effect by indexing the plugs, and that's cheaper, yes?

 

Hard to understand why one spark that lasts only a millisecond would be "better" than another...........

IF it ignites fuel, it's a good spark, and makes no difference whether the spark was 30 KV or 100KV.

Higher voltage (not hotter) sparks are needed for modified, high compression engines usually used in drag racing; the more compression, the greater the voltage needed to fire.

 

I agree there's no difference with the values mentioned above but you are closer to reality if you count on 15~18 KV.
This might be reduced in less than 10KV when engine starts and battery voltage goes down to 7~8 volts.
Every little voltage gain in primary of the coil is an advantage even if it just provides a headroom for ignition degradation .