Spark plug caps

[Rossvickicampbell]

Guys - what spark plug cap do I need - resistor or non resistor, slip onto plug cap or slip onto thread type???

ta

Rossco

[matcho mick]

yes,

[Rossvickicampbell]

yeah - good on ya MM    Very interesting reading I have seen - and now confusing.  I have been told that the older classic bikes don't need resistor type plugs - and therefore resistor type caps.  However PVL (which my bike has) have specific instructions re digital or analog PVLs and recommend plugs to suit - how do I know which one I have?

[alexbrown64]

I think i can help you there as i had the same problem... here is an email i sent to Penton who sell the PVL..
 
From: Website Contact
Sent: Tuesday, August 04, 2015 3:45 AM
To: [email protected]
Subject: Penton Website Inquiry
 
Message: Hi, i have the digital PVL for a 83' YZ125. I have the resistor cap installed but also run an Iridium resistor plug (BR9EIX) as its near impossible to get a non-resistor thin wire Iridium. My question is: Do i go back to a non-resistor cap when using a resistor plug with my digital system, or keep using the resistor cap with resistor plug. Regards, Alex Brown

Hello Alex,
 
Thank you for contacting us.  You want to use a non resistor cap.
 
Regards,
Bj Penton
Penton Racing Products
(440) 989-4474

[Rossvickicampbell]

thanks Alex - how do I know which PVL I have installed - 74 YZ360?  Also interesting as I do some more chasing that the plug cap I had installed is rated by NGK as a 5 K ohm resistor one (was on the bike) - so maybe for this weekend just replace with an LB05F which is a later type, fits and is also a 5 K ohm

And keep chasing a non resistor type as have non resistor plug and told no need on my bike - but what difference if any will a resistor plug do - no harm to performance?

thanks

Rossco

[micko]

This might help,
Power Sport Manufacturers are required to meet noise suppression standards throughout the world.  Spark Plugs alone do not provide enough noise suppression therefore resistor covers were introduced. NGK Resistor Covers are designed to reduce “Electro Magnetic Interference” and “Radio Frequency Interference” which can interfere with electronic ignition components causing misfires and poor engine performance.

[LWC82PE]

Non resistor cap

www.ngk.com/product.aspx?zpid=20083

[Rossvickicampbell]

thanks guys - managed to find 2 of the LZFH in all of Perth today so will have one tomorrow 

[alexbrown64]

thanks Alex - how do I know which PVL I have installed - 74 YZ360?  Also interesting as I do some more chasing that the plug cap I had installed is rated by NGK as a 5 K ohm resistor one (was on the bike) - so maybe for this weekend just replace with an LB05F which is a later type, fits and is also a 5 K ohm

And keep chasing a non resistor type as have non resistor plug and told no need on my bike - but what difference if any will a resistor plug do - no harm to performance?

thanks

Rossco

Rossco,

Looks like there is only the analogue PVL for your machine, which is 70186 http://www.pentonracingproducts.com/downloads/penton-parts-list.pdf
This does require a non resistor cap.. http://www.pentonracingproducts.com/downloads/PVL_Mounting_Instructions.pdf

The digital PVL needs a resistor as micko states, but not in the plug and cap.  Most plugs are resistor type now, especially the iridium ones, so in order to get a good spark, you need to run the non resistor cap.  I also have to buy a non resistor cap as the one PVL sent is a resistor type and i am already running a resistor iridium plug on my digital PVL.
I used the plug LWC posted up and searched on ebay.. http://www.ebay.com.au/itm/NGK-LZFH-SPARK-PLUG-CAP-Non-Resistor-Type-10-12-14-mm-Plug-/321737495358?hash=item4ae90c933e
and ordered that one as i am offshore at the moment and it should be waiting for me when i get back.

Cheers,
Alex

[chrisdespo]

way back in the eigties a customer had purchased a GPZ1100 the first release in australia fuel injection by Bosch fitted std with resistance plug caps the same as Z1 and z1000. the bike was sitting outside the pub and some scumbag pinched the two outside caps. no std caps in stock fitted a set of red Champion caps Bike ran like a Dog with one leg, took two caps off an old 900 and fitted problem solved has always stuck in my mind. i often check the resistance in caps on multi cylinder bikes and have even found a few crook ones on the older trail bikes with way too much resistance, it pays to check these things from time to time. from memory if you screw the plug connector out the little resistor is marked with an OHM rating sometimes even a dirty connection in the cap can cause real problems.