3.4 S spark plugs and caps

[ollyw750]

Evening all,

I'm having problems with spark plugs and caps. I have fitted a new set of plug leads (with the lead carrier fitted alongside the plugs) and found that the Champion caps won't fit, as there is not enough space between the carrier and the plug for the cap to fit. Also, I have discovered that the impedance of one of the brand new caps was more than 5 times what it should be.

The other problem I have had is that the screw-on terminals keep coming loose. I have tightened them and added a small drop of thread-lock now.

Actually, I would prefer to fit NGK plugs without the screw-on terminals, and fit some plug caps with rubber seals at both ends, also preferably NGK, although I am open to suggestions.

My questions are as follows:

What is the best plug to fit?
What are the best plug caps to fit that are designed for the bare threaded terminal?

I'm not wedded to the idea of NGK, but I have found them to be the most reliable on various motorcycles I've had. I have also had issues with quality of Champion parts in the past.

Thanks in advance,

Oliver

[sweller]

I've also used NGK for many years on my bikes and I've also had problems with the Champion stuff (both plugs and caps)....

As you probably know it's a very simple operation to fit NGK caps to silicone leads. Just snip off the old plug cap and screw on the NGK caps. A smear of vaseline or WD40 helps get the rubber parts on the lead.

NGK will be the cheapest and most readily available - a quick google shows them at £2.10 (or £2.35 for black)
http://www.trialsbits.co.uk/product_inf ... cts_id=277

You could make up your own leads from scratch or use universal HT leads, but that doesn't help the screw on problem if you use the standard type push on caps.

I'd be concerned the thread lock would effect the conductivity of the plug. I've never had to use anything in 25 years of bikes, just a good tweak with a pair of pliers.

HTH

Simon

[Martec]

Hi,

As I'm not too concerned with looks (seriously not impressed with the screw on plug heads) I have used NGK plugs and a set of standard XJ6 leads (Black), as the distributor is a specially set up 45D distributor and so also has push on connectors.

Brian

[ollyw750]

Thanks chaps. So which plug brand is the best... and what is the model number, or code?

Cheers,

Oliver

[PeteB]

For a 3.4 or 3.8 , NGK BP5ES are the 'standard' spark plug. I also use NGK push-on plug lead caps, part no. LB05F, which come with rubber seals and fit directly to the threaded end of the plug.