Having hard time putting NGK CR8EIX

[kfc.android]

So I ordered NGK CR8EIX to replace stock CR7E
(Why? Many people in Taiwan used CR8E/IX for better long distance performance)

It was nice and easy until I want to put the cap/connector(?) to the top of CR8EIX.
According to the photo below, in terms of tip, there's a big difference between stock CR7E and CR8EIX
I applied several hard pushes but the cap just won't click onto the plug. (I tried that with CR7E and is was sooo easy)

Is that means I should forget about CR8EIX and go back to CR7E?
Wonder would I face the same problem if I go with CR7EIX?
Is this ever happen to you for those who used/using CR7EIX?

Any help will be greatly appreciated.
Thanks!

[kfc.android]

Here's the photo of the "cap/connector" I mentioned

[tortoise]

[ophelia]

Unscrew the bullet top part off. Might need some pliers if it's really on there.

[Adept]

What is the difference between CR7 and CR8?

[kfc.android]

Unscrew the bullet top part off. Might need some pliers if it's really on there.

Dang, didn't know it was that easy 
Thanks a lot for your help! 

[kfc.android]

What is the difference between CR7 and CR8?

From what I read: 8 has higher cold index than 7

Quote:
A hotter plug will keep more of the combustion temp. Meaning if you could touch the part of the plug that is in the engine it would be hotter. It has nothing to do with how hot the spark is. Which is what most people believe. One of the reasons for the different heat range of plugs is, if the plug keeps too much heat it will ignite the air/fuel mixture before the ignition sends spark to the plug, the same way any hot spot in the combustion chamber will. This is bad for an engine. So the manufacturer puts a plug in that will not do this but will also be hot enough to keep from fouling easy. There are other factors but these are the main ones.
http://www.suzukicentral.com/forums/17-maintenance-repairs-tuning/47981-spark-plug-types.html

[BettinANDlosing]

Just curious, Is this for your dt300? I don't think that bike takes the cr7hsa.

[BettinANDlosing]

http://atlanticz.ca/zclub/techtips/plugs/ngksparkplug1.jpg
Everyone should download and save this chart!!!

[kfc.android]

http://atlanticz.ca/zclub/techtips/plugs/ngksparkplug1.jpg
Everyone should download and save this chart!!!

That's a really useful chart

I have listed plugs could be used on our bike just for everyone's reference:
Stock Plug: NGK CR7E

NGK Iridium: CR7EIX;     DENSO Iridium: IU22

Higher cold index
NGK Iridium: CR8EIX;     DENSO Iridium: IU24

[sklnzl]

In my knowledge ,I had come across sometime ago,In order to swap your spark plug to a higher or lower number rating ,you should first check your stock spark plug first ,i.e if the color of the tip is white then you should move to a colder plug i.e higher number,and if the tip is black then you should move to a lower number that is hotter plug.Please rectify if I am wrong .

[kfc.android]

In my knowledge ,I had come across sometime ago,In order to swap your spark plug to a higher or lower number rating ,you should first check your stock spark plug first ,i.e if the color of the tip is white then you should move to a colder plug i.e higher number,and if the tip is black then you should move to a lower number that is hotter plug.Please rectify if I am wrong .

Totally agree with you.
I inspected the tip of stock CR7E used for 5.3K miles.
It was on the lean side (White tip) so I decided to go for higher number as many people experienced in Taiwan.
I will probably do a valve adjustment pretty soon and inspect the burn after that. Might have to switch back to lower number but so far so good

[Philly]

Here's an interesting test on the NGK iridium plugs.

[zombie]

In my knowledge ,I had come across sometime ago,In order to swap your spark plug to a higher or lower number rating ,you should first check your stock spark plug first ,i.e if the color of the tip is white then you should move to a colder plug i.e higher number,and if the tip is black then you should move to a lower number that is hotter plug.Please rectify if I am wrong .

You are correct. The ONLY time to change heat ranges is when the plugs condition dictates it. The condition of the plug is a direct reflection of the fuel/air/compression inside the cylinder.