Topic: Spark plug caps/wires?

[longshanks]

I was about to buy some NGK spark plug resistor caps on Z1 enterprises when I saw the 7mm Dyna wires that have the caps built in. I think they're only a couple bucks more and you have to wire them up the the coils. Is this even possible? I thought the wires were not removable from the coils. Is there even a performance gain to be had over NGK?

[longshanks]

anyone?

[orange550]

The wires are not removable from stock coils. I tried those Z1 wires with Dyna coils they sucked. Arced thru the rubber caps to my head. Plus they have no resistance. I went with bulk coil wire and replacement NGK caps that match the originals, although they are 5 ohms resistance instead of 10. 10 no longer available.

[longshanks]

The wires are not removable from stock coils. I tried those Z1 wires with Dyna coils they sucked. Arced thru the rubber caps to my head. Plus they have no resistance. I went with bulk coil wire and replacement NGK caps that match the originals, although they are 5 ohms resistance instead of 10. 10 no longer available.

If you bought bulk coil wire how did you attach it to the coils?

[Duanob]

NGK makes wire splicers for plug wires. Google it you will find it.

[luap]

you can get the splicers at sirius con inc

[nancy]

You can remove wires from coils..you just need to perform malio-facial surgery on each coil to cut them open to expose the end, desolder, solder in HT wire. Cover up again with JBWELD, or whatever.
If your existing coil wires are hard and nasty - it is best to do it this way..or cut them close to the coil and splice in as mentioned.
Mark

[LesterPiglet]

I cut my leads close to the coil then screwed in a self tapper. Slipped over a piece of larger diameter tubing. I then cut the head of the self tapper and threaded on the new HT lead. Smeared on some silicone sealant and slipped the tubing over the join. Works perfect.

[orange550]

The wires are not removable from stock coils. I tried those Z1 wires with Dyna coils they sucked. Arced thru the rubber caps to my head. Plus they have no resistance. I went with bulk coil wire and replacement NGK caps that match the originals, although they are 5 ohms resistance instead of 10. 10 no longer available.

If you bought bulk coil wire how did you attach it to the coils?

I switched to Dyna coils. I also bought the wire kit with the soft molded-in caps. I was a little rough with one of the caps and created a very small tear in the rubber, but didn't notice right away. Bike was running poor, but I thought it was something else. I pulled over to mess with the carb idle screw and heard a 'ticking'. It was the plug arcing thru the boot into the head.

So I switched to bulk coil wire and the NGK caps. Plus this allowed me to run non-resistance plugs and keep the resistance only in the caps. Originally the 550 had 10 ohm caps, but they are not available anymore. The replacements are 5 ohm. One could add 5 ohm "R" plugs to get back to a total of 10, but I've read that it's better to keep your resistance all in one spot. The bike runs great, and plus I have the Dyna ignition, so maybe the extra voltage won't burn that as fast as it would points.

[longshanks]

Thanks for all the replies, I have a little bit of a rip in the insulation near some of the wire ends where the caps screw on and I was trying to figure out what to do. What are some performance options that people have tried and tested besides replacing the stock coils? (too expensive to replace I hear)

[TwoTired]

The wires are not removable from stock coils. I tried those Z1 wires with Dyna coils they sucked. Arced thru the rubber caps to my head. Plus they have no resistance. I went with bulk coil wire and replacement NGK caps that match the originals, although they are 5 ohms resistance instead of 10. 10 no longer available.

If you bought bulk coil wire how did you attach it to the coils?

I switched to Dyna coils. I also bought the wire kit with the soft molded-in caps. I was a little rough with one of the caps and created a very small tear in the rubber, but didn't notice right away. Bike was running poor, but I thought it was something else. I pulled over to mess with the carb idle screw and heard a 'ticking'. It was the plug arcing thru the boot into the head.

So I switched to bulk coil wire and the NGK caps. Plus this allowed me to run non-resistance plugs and keep the resistance only in the caps. Originally the 550 had 10 ohm caps, but they are not available anymore. The replacements are 5 ohm. One could add 5 ohm "R" plugs to get back to a total of 10, but I've read that it's better to keep your resistance all in one spot. The bike runs great, and plus I have the Dyna ignition, so maybe the extra voltage won't burn that as fast as it would points.

A note to the reader, the numbers presented are missing a K factor.  It's 5000 (or 5KΩ) rather the 5 ohms, and 10,000 or 10KΩ rather than 10 ohms.
Uh, yes, it makes a difference! 

Higher resistance does help to limit coil discharge heating and helps spark plug life.

Cheers,

[longshanks]

A note to the reader, the numbers presented are missing a K factor.  It's 5000 (or 5KΩ) rather the 5 ohms, and 10,000 or 10KΩ rather than 10 ohms.
Uh, yes, it makes a difference! 

Higher resistance does help to limit coil discharge heating and helps spark plug life.

Cheers,

Just picked up some new NGK 5kohms resistor caps today! 

[bollingball]

I think these are the ones you are talking about. I cut those end caps off and screwed the 5K NGK caps on. I did notice that the outside diameter of the wire was a tad bit smaller so be carfull to center it up with the screw point on the new caps. Mine have been working good with no leaks.
click on photo to enlarge.

Ken

[LesterPiglet]

Those splices are a lot chunkier than my homemade effort.

[bollingball]

That is true Lester I had to stagger them a little. I also packed them with dielectric grease. The tank covers it all up. 20-30 minutes and back on the road. I might go back next winter and solder and shrink. May change to coils with plug in wires.

Ken

[Bodi]

For Dyna coils you can just buy bulk metal core wire and four standard "distributor" terminals and caps for the coil ends. Then get the 5K NGK caps - two straight and two angled - and put it all together. A bit of dielectric grease on the coil end caps helps them slide on and stay water tight, same with the NGK cap wire boots.
With stock coils, you can cut close to the coil (2"?) and use the NGK splices or you can solder them, cover with silicon seal to about the cable diameter, and heatshrink over that. Soldering this wire is not usually easy, you should get plumbing type soldering paste to help clean the copper during heating so the solder will flow onto the metal. Use 100% isopropyl and a tooth brush to remove the paste remaining afterward - silicon sealant will not stick to it. I use a crimp connector (just the bare metal tube cut off a crimp terminal) and crimp the wire stubs together before soldering, the wires are really hard to twist together securely before soldering and the crimp holds them together then the soldering makes a really good connection. Using the crimp the gap in the cable insulation can be 1/4" or so, for twisting the wire ends together it will probably be 1/2" or more.

[chrisnoel]

The NGK 5K caps are the bee's knees.  If I'm fixing a motorcycle up the fist thing I check into is the plug cap condition.  For electronic factory ignition motorcycles I stick with the 7mm solid core wire available from most dealers and I buy it in 6ft lengths.  If I'm looking to save the original caps I test them with and Ohm meeter and pitch them if the exceed 9K ohms.  Tested the caps on my friends CB650 and found all four to be just above 5K so were calling them good.  Original coils hold up better than most would think and replacing the wires will often bring the high side windings back into specs.  If enough original lead is left triming 1/4" off of the end once in a year will do the same.   

[TwoTired]

If enough original lead is left triming 1/4" off of the end once in a year will do the same.

You shouldn't need to trim them once a year.  And doing so will quickly make the wires too short.
The cap has a screw-in contact with the wire core of the lead where spark current flows.  If that connection gets corrosion or becomes loose, the spark will arc at that connection.  This arc heat melts and softens the wire insulation (turning it to goo), so that the arcing and deterioration gets worse.
To keep the cap-to-wire connection tight and the wire end sound, you do have to cut off any length that has the insulation next to the core soft or loose.  Dab some dielectric or silicone grease or the wire end to abate corrosion.  Make certain the "screw" that is inside the cap is clean and shiny, and screw that into the wire end just until it becomes tight and no more.  Over-torquing will auger out/soften wire insulation and leave it as loose as before, inviting more arcing at that point and early failure.

Cheers,

[Duanob]

Say wuh? 1/4" a year x 35 or so years? You wouldn't have but a couple inches of wire plug wires left. 1/4" every ten years if the bike is running properly.

[kpier883]

I kind of like the ones that are on some other models including my '82 KZ1000 and my CBX.  The wire is more easily replaced and/or maintained.  I have not been able to determine whether the resistance is the same yet.  Also have not tried to install one on the 750 to see if it fits.  PO installed dyna coils, so it hasn't been a problem.

[Terry in Australia]

I bought new Dyna 3 Ohm coils and Dyna 7mm copper cored leads (and a decent crimping tool) for my Suzuki GS1000 from Z1 recently. The original crappy coils weren't worth farting about with IMO, for around 150 bucks why would you bother messing around with 30 or 40 year old coils anyway?

I'd replaced the OEM Suzuki ignition with a NOS Martek 440 but the bike was still a baastard to start, and to get it to run on all 4 cylinders I'd have to spray starting fluid into the airbox and pull the plug caps away from the plugs to create a better arc until the engine was warmed up, it was crap.

After installing the new Dyna coils and leads it is like night and day. I can leave the bike for a week and start it instantly without any choke on a warm day, or with a little choke on a cold one. It fires up on all 4 cylinders and will settle into a smooth idle of around 800 RPM right away, and as it warms up, the idle will move up to just under 1000. Great stuff, I'd thought about selling this bike for awhile now, but now that it's finally running so well, it's a keeper! Cheers, Terry.