Silicon ht lead: good or bad?

G'Day gents,

Has anyone tried silicone ht leads? I wonder if they might compliment electronic ignition and be an improvement on the traditional copper ht lead? I'm just fitting my Sparx 3 phase and 'resisted' supressor caps and beginning to wonder why I am mixing bang up to date with pre war ignition technology with traitional copper ht lead...

Love to hear what you reckon!

The silicone refers to the high temp "rubber" used for insulation. They are available with your choice of conductors. copper, graphite impregnated string or helical wound stainless wire. The helical wire is best if your ignition system will put up with the small amount of RFI generated by them. The graphite stuff is the quietest electrically but can be a bit fragile when shaken. Most electronic ignitions or voltage regulators will not put up with the large amount of RFI from solid copper core wires. Jim

Silicone is GREAT for high temp resistance.. (like near exhaust headers on car/truck engines), but the silicone has poor abrasion resistance, tears easily. A great solution to melted wires on headers/manifolds like small block Chevies with headers). It's a non issue on the bike engine. So, it's not an upgrade, IMHO.

Yes I use silicone. I also have recently worked on 2 bikes where they used 8mm instead of the correct 7mm. One of the better wires I have used is a black rubber coated/silicone filled, stranded wire. looks very plain but is technically awesome for abrasion resistance with the flexibility and dielectric qualities I like.

I use them too. It really isn't needed for the high temp resistance but it is hard to buy a good quality wire anymore that is not silicone.
Magnacore and Taylor are hard to beat. Jim

Traditional hot rod spark plug leads is this stuff I used on my Combats. Just good copper core so plugs or boots can supply the R factor as needed. Anal knowing vintage racers would store new leads in bags of rice in freezer and only pull out before a race for driest least leakage leads back when. Fat tires and fat wires look clunky on Cdo to me.

http://www.triple-c.com/Products_and_Ac ... RE&pID=375

When I fitted my Sparx 3 phase alternator and the matching Sparx regulator rectifier last year I had a real problem which I traced to the graphite leads that I had acquired, and then attached NGK 5000 ohm caps to. See my thread on this site - I can't remember the name - something with "Sparx" in it. It ultimately transpired that the resistance that was built into the modern graphite lead, when coupled with the resistance in the cap, was too much with the result that the regulator did not put out enough current to run the lights and charge the battery, as well as firing the plugs.

When, after consultation with Tri-Cor, I changed to copper ignition leads with the NGK caps the problem was resolved. That change was easier said than done; I bought the bike with graphite or silicon leads, which I replaced with a set that was supplied to me by Norvil or Andover was also not copper and resisted, and in Auckland I tried about 7 different potential suppliers before I was able to find one who could sell me copper lead.

It may be that the leads you are looking at can be used without resister caps; but it may be prudent to test them for the level of resistance before committing to them

Timely thread, I started fitting a Sparx 3-phase tonight too...

"I also have recently worked on 2 bikes where they used 8mm instead of the correct 7mm. "

Dave, I wasn't aware that 8mm was not correct - is there a resistance or suppression problem with 8mm wires?
(yep, that's what's on the bike now!)

"It may be that the leads you are looking at can be used without resister caps"

That would be great, the 8mm wires I'm running are graphite suppressed; purchased because I'm running a Tri-Spark. At the time I installed it, the 'common knowledge' was that electronic ignitions needed resistor plugs, or resistor caps, or resistor wires - but not a combination of them. So, now I'm wondering if I wrongly equated "suppressed" wires as being the same as "resistor" wires? And, would the "suppressed" wires be adequate to protect the Sparx Powerbox (and the Tri-Spark) without using resistor caps?

Thanks for any input on this one, electrickery is just not my thing.

7-8-10 or 12 mm doesn't make any difference electically . The big ones just don't fit so well with stock coils or common plug ends.

Since bigger is better :roll: somebody is probably got 14mm wires on the drawing board now.

As long as it don't short or leak much voltage then any more insulation is just for looks or heat. Its the conductor that matters most and that can get like the hi end audio controversy on what the best cable is, hehe and how anyone can tell. 8 mm is good in Commando's for its vibration abrasion on edges reserves over 7mm.
I had to rotate my old bumble bee leads twice now d/t headsteady grooving.
Trixie's set are a ticking time bomb I'd better attend to soon too.

T.C. said:

Timely thread, I started fitting a Sparx 3-phase tonight too...

"I also have recently worked on 2 bikes where they used 8mm instead of the correct 7mm. "

Dave, I wasn't aware that 8mm was not correct - is there a resistance or suppression problem with 8mm wires?
(yep, that's what's on the bike now!)

"It may be that the leads you are looking at can be used without resister caps"

That would be great, the 8mm wires I'm running are graphite suppressed; purchased because I'm running a Tri-Spark. At the time I installed it, the 'common knowledge' was that electronic ignitions needed resistor plugs, or resistor caps, or resistor wires - but not a combination of them. So, now I'm wondering if I wrongly equated "suppressed" wires as being the same as "resistor" wires? And, would the "suppressed" wires be adequate to protect the Sparx Powerbox (and the Tri-Spark) without using resistor caps?

Thanks for any input on this one, electrickery is just not my thing.

Click to expand...

As stated... if you have NON 7mm..... how do you fit it in the coil? The bike came to me after a "professional" shop installed 8mm and didn't fit the coil wire fitting that clips inside the coil...yeah just stripped the wire bent it back and shoved it in. coil boot was sloppy . ROTFLMAO
personally ...I don't care for carbon impregnated fiberglass strands on a constantly shaking commando. life can be short and then troubles start. check them every season with an ohm meter....If required, I'd use resistor caps and copper wires.
At the 02 rally I diagnosed a bad resistor wire for a guy that had evaded detection for ?years?. I jamed a plug lead from the junk box onto his bike and said "go try it". He came back from the ride with ear to ear shite eatin grin.

A shade tree like me would likely razor blade and bench grinder the 8mm to 7mm then use 7 mm boots and terminal with some RTV for grins. Kind of hard to find but here's a site with just terminals for sale.

http://www.kingsbornewires.com/category ... goryId=102

hobot said:

A shade tree like me would likely razor blade and bench grinder the 8mm to 7mm then use 7 mm boots and terminal with some RTV for grins. Kind of hard to find but here's a site with just terminals for sale.

http://www.kingsbornewires.com/category ... goryId=102

Click to expand...

Steve
Why not just buy the original 7mm sized material?
Not all that hard to find. It is even in kingsborne.
I got my last bunch of 7mm supplies at one of those exotic supply stores ....NAPA.
I think 8mm is just more available, since that was the last common wire before they went to the "coil on plug" avenue.
They even list the hotrod 7mm rajah stuff at oil furnace suppliers, though they would have to order and bring it in from the warehouse. I found that stuff while working on my oil burner. :mrgreen:

Dave I'm responding to the subject line inquire, I've no need/desire for 8 mm on my Commandos. Both Trixie and Ms Peel get copper core like the bumble bee. Trixie with points gets plugs of what ever will fire and not foul while Peel gets R plugs in cooler heat range with fine terminals like the 4 prong Platinums or cut back electrode, indexed, hook electrode kind. Dang reminds me I'm on last legs of last set of yellar/back leads, ugh, better act on it before shorted aways away.

I have been using the Magnacore KV85 plug wires on my Norton for several years. I had a set custom made to my spec. by Magnacor after trying to find the old stand by plug wire "Packard 440" which seems to be unobtainable now. The Magnacore wires started out redish and now have faded to mostly orange but otherwise look like new. Works with a Boyer, I think they cost like $34.00

7mm Packard 440 Spark Plug Wire
Still made like it was 50 years ago. This is a classic spark plug wire with a copper core. Sold by the foot @ $2.50
http://enginebarn.myshopify.com/product ... -plug-wire

What's so great about the Packard 440 wire?
I just bought some hypalon 7mm copper core wire at the auto parts store for .47 cents a foot.

Well no one would look twice at your cost cutting plain Jane leads is why.

hobot said:

Well no one would look twice at your cost cutting plain Jane leads is why.

Click to expand...

what does that mean?

what makes the Packard 440 wire worth 5 times the price of what I bought?
is there a difference?