COPS?

oz1961 · Jan 28, 2022

I have a 1995 vmax I am bringing back to life. I am considering changing over to COPS. I see some with resistors and some not. Do some vmax’s need resistors and some not? Looking at what is best for my bike. Thanks and ride safe

VMAXXIMUM · Jan 28, 2022

Generally speaking the consensus seems to be that you should run resistors with the stock ecu or risk premature failure. If you are using an aftermarket ecu like the Ignitech unit, you do not need resistors because it compensates for the reduced resistance.

oz1961 · Jan 28, 2022

VMAXXIMUM said:
Generally speaking the consensus seems to be that you should run resistors with the stock ecu or risk premature failure. If you are using an aftermarket ecu like the Ignitech unit, you do not need resistors because it compensates for the reduced resistance.

As far as I am aware it’s completely stock so thank you for your advice. I’m still torn which way to go. New coils and leads or COPS

Fire-medic · Jan 28, 2022

What year is your bike (yes, I see a 1995)? The 1985-'89 bikes use a CDI which is more-susceptible to issues after using COP's. The best way to go with COP's is to match the coil resistance to what the CDI expects to receive. The 1990-'07 bikes' CDI seems to be less sensitive to the resistance, but for best results, match the coils to what the bike wants to see.

You want more power from your coils, buy DYNA 3 ohm coils. You will have to do some fabricating to mount them, but they are hotter than COP's. Not cheap though.

The main advantage of using COP's is the ease of switching a defective one out. They do not offer a performance boost over the OEM coils. Honestly, if your coils are performing OK, I'd leave 'em alone, ensure the connectors and leads are intact, not corroded, and inspect the high-tension leads are shiny-bright, and not green with oxidation/corrosion. If they are cut the lead back about 1/4" and see if that gives you shiny wires to screw-into the coil tower. If you decide to replace any high-tension wire, ensure that the wire is the same diameter as OEM, and remove the 'wedding-band' (called an 'olive') on the OEM wire, which acts like a compression fitting when the fluted thimble-looking threaded plastic nut is tightened.

Dyna Igntion Coils Set - Single Output - 3ohm Single Plug/Single Fire | Dynatek (dynaonline.com)

MaxMidnight · Jan 29, 2022

I would start by going over the OE system first and establish what condition it's in. If serviceable then run with that while you bring the rest of the bike up to scratch.
If however you need to spend some money on it then CoP's would be worth considering.

In terms of bang for buck, if I had $660 to spend it wouldn't be on the Dynatek coils - I doubt that you would notice a significant difference and the money saved by going CoP's could be spent elsewhere on the refurbishment.