Swapping a B8HS plug for a resistor type plug?

Any body ever swap a non resistor type NGK B8HS plug for a resistor type? Having trouble with my speedo computer feeding back from electrical noise when I fire my bike.

Any Advise on this? I have a kitted 74cc engine.

Cheers!

Re: Swapping a B8HS plug for a resistor type plug?

You could do that or switch plug caps for a resistor type . Those are the 2 easiest swaps . Each , plug or cap , will add about 5k resistance to your system .

You might also consider installing something in line to the speedo to help quiet that noise .Edited 1 time(s). Last edit at 12/01/17 09:48PM by pdcomm.

Re: Swapping a B8HS plug for a resistor type plug?

Thanks for the reply! I installed a switch inline with the speedo in hopes of adding resistance. I also added a plug cap with 5K resistance. But still having electrical feedback when firing the bike. If I were to swap to a plug with a resistor, which one would best match the engine performance of the NGK B8HS?

Anything to watch out for when changing plugs? My engine runs like a dream right now with the B8HS non resistor type plug...

Cheers!

Re: Swapping a B8HS plug for a resistor type plug?

How is your speedo signal wire routed ?

If it is routed right next to a power wire from the magneto , it might be picking up interference .

And , is your speedo grounded ?

I doubt a switch will provide much resistance/filtering .

Re: Swapping a B8HS plug for a resistor type plug?

yeah one resistor or the other, don't add them up.

i'd mess with wire routing first, second you could try a carbon core spark plug wire but they do weird things with ignitons that aren't meant to use them sometimes.

Re: Swapping a B8HS plug for a resistor type plug?

The Speedo power wire is routed through an on/off switch and then to the headlight so that it gets power from my cdi. It is grounded to the headlight ground, bypassing the on/off switch.

The switch seems to help with interference. It doesn't always feedback, but when it does it is right after firing the bike. After the bike has been running for a while it won't feedback from electrical noise.

I'm more curious though to see if using a BR8HS plug in place of a B8HS would affect the kitted setup of my engine?

Thanks!Edited 1 time(s). Last edit at 12/05/17 03:01PM by capobeachvintagemopedclub.

Re: Swapping a B8HS plug for a resistor type plug?

Thanks for the advice! I already have a boot with 5K resistance and an on/off switch inline with the speedo power routing. So it sounds like swapping my B8HS plug for a BR8HS is not the best idea for performance of the engine and reliability.

Re: Swapping a B8HS plug for a resistor type plug?

I used to think it matters, but after talking with different people on it, it seems that it doesnt.

Re: Swapping a B8HS plug for a resistor type plug?

> Siezed Again Wrote:

> -------------------------------------------------------

> I used to think it matters, but after talking with different people on

> it, it seems that it doesnt.

It matters a lot , if your electrical system is marginal / weak .

Even if you have a very strong system , why tax it more than needed ?

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