NGK CR7E plugs

[TANWare]

Well the topic states the stock plug for our bikes. I am kind of dissapointed they didn't go with the CR7EIX though. The Iridium plugs have proven themselves over stock. So I've ordered mine............

[TANWare]

I should note, Taiwan has a spark plug but it isn't available here. VTA 3D now this looks like a plug.........

[TANWare]

I got my new plugs last night (NGK CR7EIX) and put it in this morning. What a pain to do the plug but is can be done without removing tupperware.

Impression once warmed up.

1.) Idle can now smoothly go down to 1,600 RPM.
2.) Power is much smoother from low RPM.
3.) Cruise at 25 MPH, apr. 3,500 RPM, is generally smoother, it did not feel like it wanted to stall before but at the throttle it was holding back.
4.) Acceleration form any roll speed is noticeably stronger at 50% throttle.
5.) Acceleration from a roll before seemed progressive, it started pulling but took 1/2 a second or so to build the pull, now it is immediate.
6.) I was not comfortable enough with the rolling acceleration at 50% throttle to ride in the speed lane on our local highway, now I have no hesitation in doing so.
7.) The sound is slightly throatier when accelerating, has more of that high performance sound.

Now there is no miracle here making the bike into a rolling rocket but it is amazing what a simple low cost change can do.

(IMHO) I attribute the change to our small combustion chamber. A normal plug can fire on any edge of the electrode and this then changes the plume profile inside the cylinder on every stroke. On a small chamber engine this makes for an even greater variance as the plume has less time and volume in the chamber to even out compared to larger cylinders. With the inconsistency the ECU and EFI are constently adjusting themselves for the worst case of the firing. This is probably also why those split fire or multi electrode plugs usually do nothing for these engines.

With the small electrode of the Iridium plug the spark location is fixed and therefore the plume is more consistent. This allows the ECU and EFI to keep the engine running more optimally for the relative RPM and throttle position. Hopefully in time this may result in even better gas mileage from having to get into the throttle less. Hopefully not worse mileage from having fun and getting into the throttle more...........

[juice]

I too noticed an improvement with the iridium plugs in my scooters , but some of the forum members insisted that it was not true . I am glad you were not only able to confirm the improvement and explain the reason so eloquently . Thanks .

[TANWare]

I think you really need an ECU and even EFI to truly benefit. Since others are timing and/or mixture locked for the worst case scenario, unless you go out of spec with those. Specifically tune them for the plug or you probably will see little to no difference at all.........

[streetdown]

What is the easy way to get to the spark plug? Under the seat?

[TANWare]

Easy I am not sure of. I took a ratchet wrench from underneath.

1.)   Place the bike on the center stand
2.)   Lie down to access underneath from the air cleaner side. Feet to the rear.
3.)   There is a forward plate underneath going to the rear swing arm where there is a gap before the swing arm. Use this area for access.
4.)   Pull of the plastic/rubber cap of the wire from the plug.
5.)   Use the ratchet wrench to loosen the plug.
6.)   Remove the ratchet and us the supplied spark plug wrench to spin out the plug.
7.)   The new plug needs the end cap removed to just show the threads.
8.)   Start the new plug by hand.
9.)   Use the supplied sparkplug wrench to spin in the new plug
10.)   Tighten with the ratchet wrench.
11.)   Replace the plastic/rubber end cap for the plug wire.

Now with the ratchet wrench you may one get 1-3 clicks or so at a time but that is enough to loosen the plug. Twist back and forth as you press the cap back on the plug, if you listen carefully you will hear it slightly click as it goes over the threads while it presses in.

Edit, this video best demonstrates what I mean by the spark can be anywhere on the plug and this naturally changes the plume profile.

[Undecided 300i rider]

It sounds like these plugs are getting the job done! I have a friend who thinks Bosch plugs are the best around. He tells me I should put in the Bosch plugs. What do you say Tanware?

[TANWare]

I have no real brand loyalty, though I have heard good about Bosch as well. It is more the materials but there can be between the brands quality issues. If bosch makes an Iridium I wouldn't hesitate either so long as you stay in the heat range......................

[Undecided 300i rider]

These are the Bosch hybrid Iridium/Platinum plugs:
http://www.amazon.com/Bosch-FGR8DQI-Platinum-Fusion-Spark/dp/B000PL2AZC

These are the Denso Iridium plugs:
http://www.amazon.com/Denso-IK20-Iridium-Spark-Plug/dp/B000M6UR82/ref=sr_1_1?s=automotive&ie=UTF8&qid=1305673407&sr=1-1

These are the Pulstar Iridium plugs:
http://www.amazon.com/Pulstar-be1i-Iridium-Pulse-Spark/dp/B003MOA25O/ref=sr_1_5?s=automotive&ie=UTF8&qid=1305673407&sr=1-5

It seems that there are quite a few manufacturers of these plugs.

[TANWare]

The Bosh or Denso should be fine. I have an issue with PulseStar. here goes aand will ry an keep as lay as possible. They use a high dischargecapacitor to for a lack of better term flahs a high voltge ark. There in lies issues;

1.) to let this flash off time needs to be spent charging the capacitor.
2.) since RPMs and the capacitor charge time doesn't the flash will occur at various timings off/after TDC.
3.) capacitors as they electronically wear out will hold less before the flah again varying timings off/after TDC

So essentially without a remap the plugs may do little to nothing or even be a detriment over a regular Iridium. even with a proper remap it may need remapping again as the capacitor wears.

Now the advertise a faster plume, which is great but again what is the benefit is the plume starts later from charging the capacitor?

[Adept]

I have changed the spark plug to CR7EIX.
Now I feel the different what you have talking about. (In hungarian we have a frase for this "the diffenrence is like sky and earth")

I felt before this hesitation between 4000 and 5000 rpm, now it is disappierd. The engine is smoother. Totally different feeling...

So thank everybody!! And let's buy IRIDIUM plug, just the best for our baby!!

[mnpugdog]

Putting mine in tomorrow.

[Vivo]

What doesn't matter much to a car... matters a lot to a small scooter engine.... fuel quality, spark plugs, battery size, tires, even the weight of the rider!  Before, I was a sceptic that all gasoline brands are the same as long as you get the right octane... However, after making lots of experiments on different gasoline brands, I found out that each perform differently from each other in my scooter...  One may not see a big difference between copper and iridium plugs in a car but a big difference in a scooter...

[Adept]

I always looking for the cheap modifications. Less money, much changing. Optimizing the system. The spark plug is like that. And the Dr. pulley rollers, the hot grips, etc... I won't buy a sport-exhaust for 500euros