spark plug
 

I just got a 2018 BSR DB41H 250 with 801 miles. Does anyone know what the correct OEM spark plug is? These usually come with a Torch plug and this has an NGK #4929 (DPR8EA-9). The plug is shot and shouldn't look like it does for only 801 miles. The previous owner may have replaced it with the wrong type.

I always upgrade to NGK and I would like to know what the OEM plug is so I can properly cross reference it.

Thanks.

Ngk DPR8EIX-9 Iridium plug https://amzn.to/48YSe0N

Thanks, but an iridium plug was never OEM on this Chinese bike. And I am not convinced the DPR8EA-9 I found in there is correct. I am more inclined to believe that DR8EA is the correct plug for two reasons. 0.9mm is too big of a gap for this application, and I don't think a protrusion is warranted either. I may be wrong but I am going on experience with many other scooter and small engine bikes.

If I knew what plug was OEM (I suspect Torch D8TC) then I can choose the correct NGK.

DPR8EA-9 - "P" is for protrusion (the electrode extends out further, "9" is for a pre-gap of 0.9mm. "IX" in place of "A" denotes an iridium plug.

update
 

So I got definitive answer on the OEM spark plug. It is a Torch D8TC, or D8RTC for the resistor option. The NGK direct equivalent is D8EA (#2120), or DR8EA (#7162) for a resistor plug. The gap should be 0.6mm-0.7mm.

NGK DPR8EA-9 (#4929), or the iridium version of that plug DPR8EIX-9 (#2202), is an incorrect application. The longer reach and wider gap are outside of spec.

Best advice is to use the recommended plug or its direct equivalent and change it every year. Many people are misled by iridium and the benefits of a premium plug. There is no real performance gain with a premium plug in such a low-tech, low-performing vehicle. Any time you change your spark plug the ride will feel better. Upgrading from Torch to NGK is enough to make a difference. In the long run your bike will be better off. A single DR8EA is less than $4.

I hope this helps someone else.

I replaced the Torch original on my 250 China bike with an NGK D8EA. It felt like I'd added a supercharger...

Well don't tell any of my bikes, I've been running that plug on my Hawk since 2016. Still the same plug with not a single issue. It burns nice and clean. I've ran the same plug on all my other China bikes and so have many others.

I too have the NGK iridium plugs in my CG engines. They work just fine. Seems to help my quad engine start better in extreme cold.

I bought a spare NGK D8EA iridium spark plug many moons ago, and finally got around to picking up a gapper. Lo and behold, it's spot-on 0.7mm out of the box, just like Matt at CSC said they usually are. Pulled the old one and it was over 0.9mm. Now the new one instantly fires up like never before. I was always a little annoyed that it would chk-chk-chk-chk-chk-chk-VROOM, and now even at 34 degrees out from a dead cold, it goes chkVROOM! Super happy.

From the Templar 250 Resource Guide:

"Spark plug: Torch D8TC (oem), NGK D8EA (copper), NGK DPREIX-9 (iridium) GAP: 0.6-0.8mm (.024-.031")"


Question for those running the iridium plug, did you re-gap the plug? .9mm is a pretty big gap for a little motorcycle coil.

I list the longer iridium plug because it's already been tested and found not to cause interference issues despite extending further into the combustion chamber than OEM but I do wonder who was the first brave/ignorant soul to install one and did they hand crank the engine first or just start it up?

Personally I went with the NGK D8EA direct replacement for the OEM Torch. So far so good but if I have any issues I may try the iridium. Back in the day I used to run palladium fine-wire electrode plugs in my 2-stroke moto-x bikes because they didn't foul like copper plugs did.

I've been running the same DPR8EIX-9 ngk plug since 2018. I never once touched the gap. I am still using it even after swapping heads. Engine has no misfires or power issues. Keep in mind this is a bike with a cam, ported head, and a decked jug with a .8mm squish gap and a flat top piston (reads, much higher than stock compression). No spark blowout issues.

The advantage of Iridium is it's durability. It will probably outlast the rest of the bike. The other advantage is that the tip being so small on the Iridium plug means the spark has a smaller area from which to jump from, giving it a more concentrated and consistent arc that can jump a wider gap, which is why it works. I would not run a .9mm gap on a copper core plug personally, and likelydrop down to a .6-.7mm gap.

I'm a huge fan of fine wire electrode plugs. I ran platinum until iridium came out. I may eventually put iridium in my Templar but thought I'd stick with copper for now, the plug was only $3 and I always carry a spare anyway.

I just looked it up and I was wrong about something. I misremembered the gap that "-9" indicates. I thought it was 0.044"rather than 0.035". I wouldn't run a 0.44" gap in these bikes but 0.035" should be just fine. My bad memory.

NGK no way,Champion plugs for me.Run ngk in my 86 250r three wheeler,would last 3 weeks, Champion would last for years.

I believe the -9, is the heat range.