Copper core "HTLEAD" is old school proper HT Lead. The silicone lead 92042 is I believe a variation on ye olde carbon string suppressor lead, it works well while the conductor lasts, but it has a tendency to burn out and can suffer from damp; on cars that use this it is intended to be replaced every few years as a service part.
Personally I would not go with the iridium plug because the electrode area is so small, it doesn't seem to self-clean well. I have had problems with the iridium sooting up. Initial sooting up was caused by a faulty HT cap but the iridium refused to clean itself, a normal plug soon sorted it out. Personally I would use the normal NGK plug, which is very good.
Forum
For Royal Enfield owners and enthusiasts
- Wed Nov 02, 2016 8:10 pm
#63798
Iridium and other precious metal tip spark plugs have superior ability to fire a spark across a wider gap, and to be less likely to suffer from minor fouling issues when an incorrect heat range plug has been fitted. Typically for most Bullets, when fitting a precious metal plug, 1 step hotter is preferred.
The ability to fire a spark across a wider gap makes it better suited when mixture strengths are not overly rich. Where as many owner modified Bullets are often jetted too rich on the Main; hence increased potential for fouling issues and the seeming need to run a hotter plug...
If you are still running points etc, use a solid copper HT lead
The ability to fire a spark across a wider gap makes it better suited when mixture strengths are not overly rich. Where as many owner modified Bullets are often jetted too rich on the Main; hence increased potential for fouling issues and the seeming need to run a hotter plug...
If you are still running points etc, use a solid copper HT lead
- Wed Nov 02, 2016 9:08 pm
#63799
I fitted an iridium plug years before the doom laden naysayers came on the scene to tell me I was wasting my money. If it so direly bad I wonder why 7 years later it is still going strong?
Copper cable for me the other stuff is crap.
Copper cable for me the other stuff is crap.
- Thu Nov 03, 2016 5:58 am
#63802
Some manufacturers state on the box to not alter the gap, dragging a gapping wire or feeler gauge across the iridium tip can damage (sprawl) the surface, resulting misfiring and a shorter life. It is sometimes possible to purchase plugs set for a particular engine, it pays to look around for them.
- Sat Nov 05, 2016 1:21 pm
#63819
If you fit a (NGK) R-suffix, R for resistive, plug (suppressor plug) then you want a non-suppressor HT cap. If it is a non-resistive plug then you want a suppressor HT cap. Copper wire HT lead is non-suppressor. Carbon-string is suppressor HT lead (and pretty useless).
There is a reason for using a suppressor in the HT system and it is not just to reduce radio interference. It is a "LR" circuit, the HT coil is a coil "L", the resistance of the suppressor "R" alters the time constant resulting is a 'tighter' spark.
The iridium did not cause sooting up on my bike, that was another cause, but I am not alone in having had issues with the iridium. If you look at the iridium electrode, it is the size of a pin head. When a plug gets dirty the spark has to find a clean spot to spark from, they are supposed to get hot enough to self clean; once they fail to find a clean spot they start missing, lose heat and cannot self-clean, a larger electrode increases the probability of finding a clean spot and thus keep running. You may get many many years from an iridium, the same may be said for a normal plug. Some Bullets are somewhat prone to sooting (hence the Twinspark). Just a caveat, YMMV
If you run the motor hard, race it, it gets hot, so you need a 'cold' plug (bigger NGK number). If you run the engine gently you may want a 'hot' plug i.e. so its electrode nose runs hotter and thus self-cleans. I'm running my C5 on BPR5ES which seems to be half a step hotter than the standard '6'
https://www.ngk.de/fileadmin/Dokumente/ ... ode_en.pdf
BPR6ES - The "B" is 14mm, "P" is projected insulator, "R" is resistive, "6" is the heat, "E" is 19mm reach, "S" is copper electrode.
This is for the 500cc EFI (NB), the earlier 500 Bullet takes a B8ES, Do Note the lack of the P for projected nose.
BTW the BPR5ES is for a 1 litre Vauxhall Nova (long gone but I still had a NOS set), the BPR6ES is generally sold for lawnmowers. They are close in heat (half a step?) but the construction/appearance of the "5" is much better than the "6" (go figure).
There is a reason for using a suppressor in the HT system and it is not just to reduce radio interference. It is a "LR" circuit, the HT coil is a coil "L", the resistance of the suppressor "R" alters the time constant resulting is a 'tighter' spark.
The iridium did not cause sooting up on my bike, that was another cause, but I am not alone in having had issues with the iridium. If you look at the iridium electrode, it is the size of a pin head. When a plug gets dirty the spark has to find a clean spot to spark from, they are supposed to get hot enough to self clean; once they fail to find a clean spot they start missing, lose heat and cannot self-clean, a larger electrode increases the probability of finding a clean spot and thus keep running. You may get many many years from an iridium, the same may be said for a normal plug. Some Bullets are somewhat prone to sooting (hence the Twinspark). Just a caveat, YMMV
If you run the motor hard, race it, it gets hot, so you need a 'cold' plug (bigger NGK number). If you run the engine gently you may want a 'hot' plug i.e. so its electrode nose runs hotter and thus self-cleans. I'm running my C5 on BPR5ES which seems to be half a step hotter than the standard '6'
https://www.ngk.de/fileadmin/Dokumente/ ... ode_en.pdf
BPR6ES - The "B" is 14mm, "P" is projected insulator, "R" is resistive, "6" is the heat, "E" is 19mm reach, "S" is copper electrode.
This is for the 500cc EFI (NB), the earlier 500 Bullet takes a B8ES, Do Note the lack of the P for projected nose.
BTW the BPR5ES is for a 1 litre Vauxhall Nova (long gone but I still had a NOS set), the BPR6ES is generally sold for lawnmowers. They are close in heat (half a step?) but the construction/appearance of the "5" is much better than the "6" (go figure).
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