So What Plugs Do You Use ?

[old trials fanatic]

Sitting in the pub the other day talking bikes as you do the subject of spark plugs came up.

Now the manufacturers have all "recommended" a grade of spark plug but that usually takes into account lots of peramiters which may or may not be applicable to how we use our bikes today. Very few now use them flat out on the road between sections for example.

Now the old James seems best on an NGK BP5HS nothing like the manufacturers would have recommended.

So what do you find is the best plug to use?

This may be helpfull information to newbies to the wonderful world of twinshocks and Pre65 so dont keep it to yourself.

Are iridium plugs worth it ? didnt seem to be an improvement when i tried one but that was in the James and others may have found different.

[motovintage]

I like the irridium plugs, they foul less and last longer,

I did 200,000 miles in the Nissan on one set, they were barely worn.

I'm not sure a trials bike can benifit from irridium plug, I ran a NGK BR6EIVX in the montesa and never fouled, can't get those anymore, using a B6ES now, would rather have at least a BR6EG...oh well

[jon v8]

It may not be the exact answer you were looking for,but I use lots of NGK plugs in my Land Rover garage - the bulk of which are the BPR6ES.These are used in all the old Rover v8's.Its a basic,old fashioned plug that works very well - even with LPG.I dont think you can go far wrong with NGK,just find the right grade for your use.

Later ones were specced with a platinum tipped plug with a very wide gap,even though it is the same engine.All it did was give the coil packs and plug leads a hard time,often burning them out.My point of dribbling on about this is that you simply dont need high tech plugs,or big spark gaps - just a decent plug in good condition.What is far more important is how the spark is made,my 1970's Yamaha's still work well on their original points etc.What never ceases to amaze me is how well Bantams and the various Villiers 2 stroke engines now run with the electronic PVL or similar systems.

[nh014]

Identifying the "best" plug is a little like selecting the "best" twinshock. Standard NGK's are great, but I've had better results over the past couple of years using Champion PowerSport 8405 plugs in my 348 Cota's. Here is what Champion says about the PowerSport plugs.

"Champion PowerSport spark plugs are designed to deliver unmatched performance. These plugs are specifically engineered to increase power and reduce fouling in PWCs, snowmobiles, motorcycles and ATVs. These high performance plugs provide more power for quicker acceleration and less fouling providing faster throttle response. Champion's technology offers a variety of innovative features including the increased bore volume between the shell and the core nose to promote better scavenging of deposits that cause fouling. The Champion-developed Mag Suppressor controls damaging RFI (Radio Frequency Interference) without reducing ignition performance. Projecting the core nose past the shell results in reduced misfire and more stable combustion. The Champion exclusive copper core ground electrode runs over 200

[axulsuv]

I would have to say Iridium plugs in our old bikes can't be beat , They produce a better spark with less energy than standard plugs .

I'm personally fond on ND/ DENSO plugs over all others .(lots of years wrenching on toyotas , and have never seen a failed ND , without outside issues ...) NGK's work , But the ND iridium I put in fantic two years ago has shown no discernable wear and still fires first kick , hot or cold ... And has this perfect light tan shading ...

Glenn

[ausy300pro]

Another vote for the Nippon Denso iridium plugs from me, only plug I have ever fitted that did actually seem to make a performance difference (that was on a highly tuned race bike engine), but always perform well, and require less voltage for a good spark plus long lasting, only downside is the range is not as big as the NGK iridium plugs, NGK iridium being second choice, in the long run no difference in cost.