| Most "NGK"s are copies, not original items from the NGK factory. They can have the wrong heat rating and leak out pressure. This pic shows the fake one I bought that had "painted" metal that flaked off a little on the ground electrode. After riding with it 2 miles it showed no deposits on any of it, probably because it got too hot to allow them, that and the fact that the painted metal prevented deposits. The true one (iridium) on the left shows normal deposits. But many of them just have a yellow/gold colored metal that isn't painted.  On my video about this topic I said it was probable that all the fake copies were different than their heat range # indicated. Well, I just measured the distance from the threaded body end to where the ceramic contacts the metal and found that the copies were significantly longer. I had cut a strip of thin plastic from a plastic drinking bottle 5mm wide and 35mm long and inserted it into the plug body to measure distance A. I used a black marker to mark the plastic even with the end of the plug body. Here's the results below. The fake NGK's all had distances more than the genuine NGKs which means they will all run hotter and possibly cause auto-ignition. The longer the distance is that the ceramic is exposed to the combustion heat/pressure, the more heat they absorb.   NGK's website gave this list of authorized dealers but my last order of NGK plugs from AutoZone was fulfilled with non-genuine NGK's. Dennis Kirk isn't on their approved list and I've also bought fake NGK's from them. I wish we could just buy directly from NGK online but they only sell through distributors. Take note: www.ngk.com is not the NGK factory site and although they are authorized distributors they sell fakes. https://ngksparkplugs.com/ is the official NGK site.  Here's the listed prices for a NGK BR8HS #4322: Summit Racing $2.99, Advance Auto Parts $3.99, O'Reilly Auto Parts $4.49, NAPA $4.29 Here's the listed prices for a Denso IWF24 #5380 (sub for NGK #BR8HIX) : O'Reilly Auto Parts $9.99, NAPA $13.99 SHIPPING: NAPA wants $28 for shipping. Advance wants $9. Places that sold me fake NGK's: ngk.com, Autozone, Summit Racing, Dennis Kirk NGK code chart: click here Things are getting worse economically and some of these distributors are opting for NGK copies to save a few bucks. I just tested some plugs I got from Summit Racing and the only clues that they are copies is the golden color, their longer ceramic cones, and that they cause little blips of the engine cutting out while accelerating (possibly when the dynamic compression is the most).  I asked NGK sellers on EBAY where they bought their NGK's from and three of them said "Niterra North America" which is NGK in USA. But one of them, foreigndomesticautoparts (https://www.ebay.com/usr/foreigndomesticautoparts), replied "We get our spark plugs from NGK USA direct. Unfortunately NGK does not make the spark plugs 100% in Japan any longer. Our current inventory is "Assembled in Thailand, Parts Made in Japan". I'm sure the "Japan parts" are the remaining parts from the Japanese location which has shut down. Once it runs out it will probably be 100% made in Thailand or somewhere else." In April 2023, the company rebranded from NGK Spark Plug Co., Ltd. to Niterra Co., Ltd., reflecting a broader focus beyond spark plugs. In March 2023 NGK Spark Plug Co, headquartered in Nagoya Japan, announced plans to discontinue the manufacture and sale of certain insulator products at it China site in Handa City due to declining demand and increased competition. I know in 3rd world countries the sale of motorcycles has reduced in favor of electric scooters. This is probably the reason for the lack of demand, that and the fact the global economy is still declining after the pandemic lockdowns (which is a whole other story in itself. They were intentionally mandated to cause economic harm. The globalists want a reduced population and reduced consumption of Earths resources, especially petroleum because at the same usage rate of 2019 we only have one decade more of decent gas prices due to its availability declining.) Why I'm Rejecting NGK: 1. the main NGK factory in Japan has shut down and so as the NGK distributors run out of original plugs they will sell copycat plugs which is already happening. 2. My last three purchases of NGK plugs have been shitty copycat plugs and I'm tired of wasting my money. 3. I've found good replacements with Champion and Autolite.  Here's the NGK code breakdown so you'll know what specs to look for in a different brand:   DENSO iridium spark plugs commonly available: #22 heat range, 13mm thread reach Denso 5379 (W22FS-U) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 1/2" (13mm) thread reach, hex size 21mm (13/16"), Heat range: 22 (equal to NGK's 7), U groove at ground electrode, O'Reilly $10 Denso 5383 (IUF22) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 1/2" (13mm) thread reach, hex size 5/8" (16mm), Heat range: 22 (equal to NGK's 7), O'Reilly $10 #22 heat range, >13mm thread reach Denso 5327 (IT22) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, .7" (18mm) thread reach, hex size 5/8" (16mm), Heat range: 22 (equal to NGK's 7), O'Reilly $9.50 Denso 5310 (IK22) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 5/8" (16mm), Heat range: 22 (equal to NGK's 7), O'Reilly $11.50 Denso 3419 (#22) Iridium, 5000 ohm resistance, 1.1mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 5/8" (16mm), Heat range: 22, platinum chip ground electrode (equal to NGK's 7), O'Reilly $12.99 Denso 5348 (IK22G) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 5/8" (16mm), Heat range: 22, U groove at ground electrode (equal to NGK's 7), O'Reilly $9.50 Denso 5313 (IQ22) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 5/8" (16mm), Heat range: 22, U groove at ground electrode (equal to NGK's 7), O'Reilly $9.50 Denso 5361 (IU22) Iridium, 5000 ohm resistance, .9mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 5/8" (16mm), Heat range: 22, U groove at ground electrode (equal to NGK's 7), O'Reilly $9.50 Denso 3372 (#22) Iridium, 5000 ohm resistance, 1.1mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 5/8" (16mm), Heat range: 22, platinum chip ground electrode (equal to NGK's 7), O'Reilly $16 #22 heat range, >19mm thread reach Denso 5340 (ITV22) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 1" (25mm) thread reach, hex size 5/8" (16mm), Heat range: 22, U groove at ground electrode (equal to NGK's 7), O'Reilly $10.50 Denso 5345 (IKH22) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 1.06" (27mm) thread reach, hex size 5/8" (16mm), Heat range: 22, U groove at ground electrode (equal to NGK's 7), O'Reilly $10.50 #24 heat range Denso 5380 (IWF24) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 1/2" (13mm) thread reach, hex size 13/16" (21mm), Heat range: 24, U groove at ground electrode (equal to NGK's 8), O'Reilly $10 Denso 5316 (IW24) Iridium, 5000 ohm resistance, .7mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 13/16" (21mm), Heat range: 24, U groove at ground electrode (equal to NGK's 8), O'Reilly $9.50 Denso 5341 (ITV24) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 1" (26.5mm) thread reach, hex size 5/8" (16mm), Heat range: 24, U groove at ground electrode (equal to NGK's 8), O'Reilly $12 #27 heat range Denso 5329 (IT27) Iridium, 5000 ohm resistance, .6mm electrode gap, 14mm thread dia, .7" (18mm) thread reach, hex size 5/8" (16mm), Heat range: 27, U groove at ground electrode (equal to NGK's 9), O'Reilly $10.50 Denso 5347 (IKH27) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 1.04" (26.5mm) thread reach, hex size 5/8" (16mm), Heat range: 27, U groove at ground electrode (equal to NGK's 9), O'Reilly $15 Denso 5363 (IU27) Iridium, 5000 ohm resistance, .9mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 5/8" (16mm), Heat range: 27, U groove at ground electrode (equal to NGK's 9), O'Reilly $10 #29 heat range Denso 5318 (IW29) Iridium, 5000 ohm resistance, .7mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 13/16" (21mm), Heat range: 29, U groove at ground electrode (equal to NGK's 9.5), O'Reilly $17 #31 heat range Denso 5319 (IW31) Iridium, 5000 ohm resistance, .7mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 13/16" (21mm), Heat range: 31, U groove at ground electrode (equal to NGK's 10), O'Reilly $17 Denso 5323 (IQ31) Iridium, 5000 ohm resistance, .8mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 5/8" (16mm), Heat range: 31, U groove at ground electrode (equal to NGK's 10), O'Reilly $17 Denso 5364 (IU31) Iridium, 5000 ohm resistance, .9mm electrode gap, 14mm thread dia, 3/4" (19mm) thread reach, hex size 5/8" (16mm), Heat range: 31, U groove at ground electrode (equal to NGK's 10), O'Reilly $17 Also another brand to consider is Champion:  Another plug brand to try is Brisk.  So far I've found that Champion is tthe best over Autolite and Denso. I can't find the Bosch plug I need in the USA and I haven't tried a Brisk yet. My Youtube videos on this subject: Part 1, Part 2, Part 3 |