Plug Caps

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Coyote
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Plug Caps

Post by Coyote »

Does anyone have the part number for the Suzuki non resistor plug caps? These are not shown on any fiche I can find. I am thinking about replacing the high tension leads as well. Any recommendations?
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Re: Plug Caps

Post by oldjapanesebikes »

I think the NGK part number is LZFH.
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Re: Plug Caps

Post by diamondj »

There's still one style of the NGKs that you can take apart and remove the resistor from. I did this on my GS1000 and replaced the resistors with the same length and diameter of thick copper rod from the local hobby shop.

I'll have to see if I still have the boxes for the plug caps.

Jim
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Re: Plug Caps

Post by oldjapanesebikes »

diamondj wrote:There's still one style of the NGKs that you can take apart and remove the resistor from. I did this on my GS1000 and replaced the resistors with the same length and diameter of thick copper rod from the local hobby shop.

I'll have to see if I still have the boxes for the plug caps.

Jim
Yep - you can do that with the LB05F and LB05FP. The '05' is a 5K ohm resister which is about a cm long. Over in the 'Electric' thread I think Allan showed one of these in pieces. The hoods decode as L for 90 degree elbow, B for 14mm diameter thread, F for the threaded post (no nut), the the P for having a waterproof cover.
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Re: Plug Caps

Post by Coyote »

I just bought 3 of the LB05F caps. They DO NOT have any slots on the copper and can not be disassembled. Bummer! The whole reason for buying these was to get rid of the resistor. Back to square one. Jim, did you find the boxes?

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Re: Plug Caps

Post by Blokhead »

The resistor in yours is in the other end. That little toothed washer is what holds it all together.

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Re: Plug Caps

Post by Coyote »

Actually Jim, the number should be on the caps. Least wise it is on these I just bought.
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Re: Plug Caps

Post by jabcb »

As oldjapanesebikes said, NGK has a non-resistor plug cap. Its the LZFH.
For more info see: http://www.ngksparkplugs.com/docs/Resistor_Covers.pdf
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Re: Plug Caps

Post by oldjapanesebikes »

I have had those NGK caps apart before - the resister is in line with the high tension lead. Perhaps they have changed the design but I don't recall it being a problem. And I just noticed Blokhead has posted a photo which looks like I remember it. :up: :up:

And just out of curiosity, why do you want non-resister caps anyway ? 8) If you are running electronic ignition, then you need some resistance, plus it keeps you on friendly terms with the neighbours as it won't mess up their TV and radio reception every time you drive by. 8)
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Re: Plug Caps

Post by Coyote »

OK. Someone will have to explain the benefit of a resistor in the HT leads. This some how seems counter productive to me.
As far as RFI, all TV signals are now digital, so the lack of resistors won't cause interference. Most modern radios are shielded against outside interference as well.
Doesn't the resistor reduce the voltage getting to the plug?
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Re: Plug Caps

Post by tz375 »

As I understood it, RF noise is bad for electronics such as Digital dash and CDI etc, but with suppressed cables and/or resistor plugs, surely you don't need resistor caps as well.

What combinations work or alternatively should be avoided. I have a dyna ignition, carbon filament leads (suppressed), Resistor caps and resistor Iridium plugs and I'm sure that two out of three could be removed.
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Re: Plug Caps

Post by oldjapanesebikes »

tz375 wrote:As I understood it, RF noise is bad for electronics such as Digital dash and CDI etc, but with suppressed cables and/or resistor plugs, surely you don't need resistor caps as well.
I suspect you are correct. 8)
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Re: Plug Caps

Post by diamondj »

The NGK plug caps I used on my GS1000 are VB05F. These have the screw slot on the plug end that allows you to remove the resistor and replace it with a piece of solid copper tube from the local hobby shop.

I'm running the 8.8mm Accel suppression wires and a Dyna ignition and the spark was a bit fatter and more intense when I swapped out the resistors.

Hope this helps!

Jim
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Re: Plug Caps

Post by tz375 »

Thanks Jim,
Mine are new and have the screw out plug connector. I unscrewed one and the screw in part came out with a short sporing. I can hear the resistor moving around but does it come out through the plug end as well?
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Re: Plug Caps

Post by diamondj »

tz375 wrote:Thanks Jim,
Mine are new and have the screw out plug connector. I unscrewed one and the screw in part came out with a short sporing. I can hear the resistor moving around but does it come out through the plug end as well?
Hey Tzer,

The resistor should have followed the spring dropping out of the plug cap. Try giving it a tap on the palm of your hand....

Jim
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