Copper core or silicone HT leads?
- ErlingW
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Copper core or silicone HT leads?
06 Oct 2026 23:08
Hello everyone!
I've just completed the installation of a Dynatek ignition system and coils, on my 1976 Z650, and everything went real easy. Except for the very weak spark!
Battery is good, ignition is on time. I was advised to use silicone HT spark plug leads, but now I'm not so sure anymore if they are the correct to use..
I will try the relay solution - so to eliminate any voltage drop from the starter button or kill switch, today.
What do You guys think - are the silicone leads any good on this bike?
I've just completed the installation of a Dynatek ignition system and coils, on my 1976 Z650, and everything went real easy. Except for the very weak spark!
Battery is good, ignition is on time. I was advised to use silicone HT spark plug leads, but now I'm not so sure anymore if they are the correct to use..
I will try the relay solution - so to eliminate any voltage drop from the starter button or kill switch, today.
What do You guys think - are the silicone leads any good on this bike?
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- kimchella
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Re: Copper core or silicone HT leads?
06 Oct 2026 23:49
Hi, I have used silicone leads with Dyna ignition and the wired George relay set up. Starts on first press of the start button, great spark and runs extremely well. Definitely recommend wired George relay set up as you will get correct power to your coils.
Rich.
Rich.
KZ650B1 frame number 225
New Zealand
New Zealand
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- Warren3200gt
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Re: Copper core or silicone HT leads?
07 Oct 2026 00:15 - 07 Oct 2026 00:19
Copper multi strand core ht and wired george relay mod to eliminate voltage drop from the 50 yo loom and swiltches.
Last edit: 07 Oct 2026 00:19 by Warren3200gt.
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- zed1015
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Re: Copper core or silicone HT leads?
07 Oct 2026 02:31 - 07 Oct 2026 02:33
Doesn't matter what bike the Dyna is on, silicone leads will work just fine.
They are all i use on my 5 zeds with no issues and have very strong sparks even without that Wired George malarky..
I presume you are using the correct 3 to 5 ohm Dyna coils.
They are all i use on my 5 zeds with no issues and have very strong sparks even without that Wired George malarky..
I presume you are using the correct 3 to 5 ohm Dyna coils.
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- Nessism
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Re: Copper core or silicone HT leads?
07 Oct 2026 04:50
The OEM wires are 7mm copper core, with 5k ohm resistor caps. You can use automotive-type suppressor HT leads instead, but be sure to use a non-resistor cap, or remove the resistor inside the cap and replace it with a slug of copper.
Ed
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- ckahleer
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Re: Copper core or silicone HT leads?
07 Oct 2026 04:58
Before installing a relay, run a wire straight from the battery to the coils and see if you get stronger spark. If not, a relay won't help.
Note: Once the bike is started this way, you will have to disconnect the wire to shut it off.
Note: Once the bike is started this way, you will have to disconnect the wire to shut it off.
97 ZL600
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Re: Copper core or silicone HT leads?
07 Oct 2026 07:54 - 07 Oct 2026 07:54
Thanks for the reply! I just bought a new wiring harness, so I'm hoping that would perform better than the old one.
I also am a fan of copper core leads, but since I already have the silicone ones fitted, I might as well try the relay option first.
I also am a fan of copper core leads, but since I already have the silicone ones fitted, I might as well try the relay option first.
Last edit: 07 Oct 2026 07:54 by ErlingW.
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Re: Copper core or silicone HT leads?
07 Oct 2026 07:56
Yes, I have the 3 ohm coils.
Thanks for the reply!
Thanks for the reply!
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- Nessism
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Re: Copper core or silicone HT leads?
07 Oct 2026 09:41What is a "silicone" HT lead? The car type with a suppressor (resistor) core?Thanks for the reply! I just bought a new wiring harness, so I'm hoping that would perform better than the old one.
I also am a fan of copper core leads, but since I already have the silicone ones fitted, I might as well try the relay option first.
Again, only one resistor element allowed. Either use a resistor cap, resistor plug, or resistor HT lead. Don't use more than one, such as supressor wires and resistor plugs, etc.
Ed
Carb O-ring Kits : www.kzrider.com/forum/14-vendor-forum/62...rburetor-o-ring-kits
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1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
Carb O-ring Kits : www.kzrider.com/forum/14-vendor-forum/62...rburetor-o-ring-kits
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
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- zed1015
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Re: Copper core or silicone HT leads?
07 Oct 2026 12:22Silicone HT leads are simply leads with the outer sheath made of silicone which has a higher resistance to heat and chemicals etc compared to rubber and commonly associated with fiberglass impregnated carbon cores but are also available with copper or steel wire cores dependant on the intended application,.What is a "silicone" HT lead? The car type with a suppressor (resistor) core?
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- Wookie58
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Re: Copper core or silicone HT leads?
07 Oct 2026 13:12
My Taylor leads have the fiberglass/carbon cores
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Re: Copper core or silicone HT leads?
07 Oct 2026 14:46Those sound like the suppressor type, with resistance.My Taylor leads have the fiberglass/carbon cores
Ed
Carb O-ring Kits : www.kzrider.com/forum/14-vendor-forum/62...rburetor-o-ring-kits
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
Carb O-ring Kits : www.kzrider.com/forum/14-vendor-forum/62...rburetor-o-ring-kits
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
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