Spark plug type ..
Standard heat range
....U.S., Canadian, Australia, Italy So. Africa..NGK DP7EA-9, ND X22EP-U9 (All other)..NGK DPR7EA-9, ND X22EPR-U9 ..
Optional heat range
....U.S., Canadian, Australia, Italy So. Africa..NGK DP8EA-9, ND X24EP-U9 (All other)..NGK DPR8EA-9, ND X24EPR-U9
Spark plug gap
0.8-0.9 mm (0.03- 0.04 in.)
Which NGK Plug? My book says DP7EA-9 or DP8EA-9 for US models.
The resistor spark plugs won't make a difference. You need to gap them correctly though.
Check for spark
: Gap your plugs! Remove a plug and put the wire back on. Hold the end of the plug to ground with something insulated, crank the engine and see if you have spark at the plug. Do this to all the plugs.
I should correct myself a little here. You could have wet plugs which would mean you are getting fuel to the cylinders but wet plugs could also tell you you are getting too much fuel to the cylinders also. This could cause your plugs to foul out and prevent you from getting spark. So if you have wet plugs clean them off and do the "spark plug test" to make sure the problem isn't electrical. Then once you know you have good spark you can eliminate that part of the problem and see that it's now a fuel problem. If you don't have spark and the plugs are wet you know that the fuel system is working and your problem now is electrical. Sorry I didn't make it more clear before.
NGK's are the way to go. NGK DP7EA-9 Thats what the book calls for. Gap is .8~.9mm or .032in~.036in I worked for Nissan for 10 years and stand behind the NGK plugs.
I recently installed champion plugs on my bike and it ran like crap. After only 20 miles on the Champion plugs, I replaced them with NGK plugs and the difference is amazing. DC
The advantage is (they claim) "Longer life, lower fuel consumption,smoother running,Improved ignition efficaintcy-giving enhanced power and acceleration" The part that matters really is the "improved ignition efficaincy" as iridium can "spark hotter" at a lower voltage. Given our feeble electrical system, anything that uses less power is good. The part number is 7803 at Advanced Auto. The plug is the DPR7IX9. KM
Worn plugs cause hard starting My spark plugs had about 13,000 miles on them and I was beginning to experience multiple tries to get the engine started, hot or cold. Figured it was time for new plugs. On Mike O's recommendation I installed new iridium spark plugs, gapped to .035'', anti sieze on the threads and torqued to 144 inch lbs (12 ft pounds). Now starts first time every time, hot or cold. Barely have to touch the start button. Thanks Mike, they really work. NGK DPR7EIX-9. About $10.00 each, but I think they will be worth it. The bike will probably fall apart before I have to change them again. Dennis in Maryland
I had the same experience with these last year, Dennis. Now I just have to barely breathe on the start button and she starts right up. I fugured they're well worth the slight extra cost. A lot of us spend way more than that on cosmetic upgrades and shiny chrome bits. I bought mine at Shade Tree for abt $8 ea. They should last longer, and I since I also keep detailed track of my gas mileage all the time, I also noticed an average increase of about 2 MPG after installing them See if you notice the same thing.... -Tim S.
I do think engines run better on them as they require so much less voltage to produce a better spark.
I priced Iridium NGK at all my mail order suppliers and finally bought them from Chaparral at $7 each last year.
OK, you guys talked me into it. I found them at Motorcycle Pro Shop for $7.31 plus shipping & handling. Might be a pretty good price if anyone else wants some.... http://tinyurl.com/b4pmu
Product ID: DPR7EIX-9 Product Name: NGK IRIDIUM SPARK PLUG Product Price: $7.31 Quantity: 4 SubTotal: $29.24 Shipping: $7.00(Regular Shipping) Handling: $2.00 State Tax: $0.00 Country Tax: $0.00 Grand Total: $38.24
Also try Sparkplugs.com
Just thought I'd mentioned this as it might save someone a few bucks. There was a discussion on the group a little while go about these plugs (DPR7EIX-9) and where to get them. The internet lowest price was around 7 bucks plus shipping. I decided to get some before the Gathering and thought I'd try locally to save the shipping. I looked on the net at the chains here locally (Autozone, O'Reilly's, and Advance Auto) and they were all around 10.xx or so. In talking to Dan Tadrick of the group he mentioned he had them and the part number is 7803. Well, if you search for DPR7EIX-9 at the Advance Auto site is comes back at 10.99. However if you put in just 7803, you get several things with the same part number, but one of them is the NGK plug for only 6.96. What's up with that? Anyway, I went to the local Advance store and it is the same plug. So if you happen to have an Advance store nearby (mostly east and some in the midwest), the price is as low as the internet without the shipping. (And yes I'm an accountant so maybe Freak is right about the beancounter part :-). John STL,MO
If you have a Sears Hardware store nearby, socket# 943330, 18mm, 6pt, 3/8" drive works great for all plug locations. If not, try Sears.com.