RESIST OR NON-RESIST THAT IS THE QUESTION

[Adamc]

My bike is a 1980 US import at heart. It runs electronic TCI ignition which I understands need a resistor plug or plug cap (not both).
I checked the INSTALLED plugs which are NGK BP7ES (Non-Resistor type)
I therefor assume the Plug Caps are resistor type which are NGK, but carry no markings. How can I check they are / are not resistor plugs?

I need to know as the Moto Gadget kit need a resistor ignition.

 

[willis]

If they are NGK caps they should have lightly laser printed code on them in gold. Non resistors ar LZFH. Resistor type are LB05F

 

[atom4488]

Ohmmeter wouldn't lie either!

 

[Grewth]

I'd be more inclined to trust a good ohm meter too.
There's loads of fake NGK stuff floating around, I wouldn't particularly trust what the writing says

 

[Adamc]

Ohmmeter wouldn't lie either!

I have such a tool (two in fact) but apart from continuity testing (Beeeep).....No idea how they work!

 

[jpdevol]

I have such a tool (two in fact) but apart from continuity testing (Beeeep).....No idea how they work!

The meter you have, if digital, may be a Klein or a version similar. So to get the beep means it's typically on Ohms x1. To advance the function to another Ohm setting, press the "SEL" button. For plug caps Ohm x20K. One probe in each end of cap..

 

[atom4488]

I have such a tool (two in fact) but apart from continuity testing (Beeeep).....No idea how they work!

Adam, not sure if you are pulling our leg or not...from what I have seen so far, you seem more than competent. If not, I'm sure basic ohmmeter checks can be added to your skill set readily. This coming from a guy whose weak suit, by far, is anything electrical/electronic!

 

[Grewth]

Just out of interest, what happens if you run the system with non resistor plugs and caps ?
I presume it will kill the TCI ignitor box.
But instantly or over a period of time ?

 

[Adamc]

The meter you have, if digital, may be a Klein or a version similar. So to get the beep means it's typically on Ohms x1. To advance the function to another Ohm setting, press the "SEL" button. For plug caps Ohm x20K. One probe in each end of cap..

View attachment 225468

Thanks JP.

 

[Adamc]

Adam, not sure if you are pulling our leg or not...from what I have seen so far, you seem more than competent. If not, I'm sure basic ohmmeter checks can be added to your skill set readily. This coming from a guy whose weak suit, by far, is anything electrical/electronic!

With you on your last sentence @atom4488. But always willing to learn. Pulled plug off wire and a little metal ‘blob’ flew off the top as the wire came away, bugger! Seems to be a thin glass tube with wire core down the centre. So I guess it’s a resistor type plug as described on NKG site.
Put meter probes on each end of cap @20 I think and got 5.46 reading.
No markings on plug a dark red type.

Would it be best to get two new non resistor caps, and use resistor plugs which I already have bought?

 

[Adamc]

Just out of interest, what happens if you run the system with non resistor plugs and caps ?
I presume it will kill the TCI ignitor box.
But instantly or over a period of time ?

Good question @Grewth. As I understand resistor plugs give weaker spark than non types. So running both items with resistors may well give almost no spark(?). Therefore running both items with no resistors may well fry delicate electronics I suppose.

 

[jpdevol]

Yep. Non-resistor plugs are gonna be a thing of the past so a change to non-resistor caps seems prudent.

When D8EA's are gone the 750 Honda guys are gonna crap as those caps are "special"

 

[Adamc]

Yep. Non-resistor plugs are gonna be a thing of the past so a change to non-resistor caps seems prudent.

When D8EA's are gone the 750 Honda guys are gonna crap as those caps are "special"

Good advice JP, thanks again.

 

[peterg]

BPR7ES (resistor) plugs and LZFH (non-resistor) caps is the combo you need.

 

[Adamc]

BPR7ES (resistor) plugs and LZFH (non-resistor) caps is the combo you need.

Thanks @peterg already have those plugs, now look for the caps.
Ta Ads.

 

[mike in idaho]

Good question @Grewth. As I understand resistor plugs give weaker spark than non types. So running both items with resistors may well give almost no spark(?). Therefore running both items with no resistors may well fry delicate electronics I suppose.

Actually, if the coil is up to the task power wise, adding resistance will force the voltage to build up higher to jump the spark plug gap. Up to the limits of the coil output, that extra voltage will create a hotter spark, get past that point and you will start having misfires.
Earlier plug caps had a removable center that can be unscrewed and the resistor removed, to be replaced with a piece of brass tube or solid copper wire.