2013 RMZ 250 - Another Spark Plug Query

[BOLT SPEEDMAN]

So frustrated. I ordered a couple of new plugs for my bike and went to switch one out last night. I ordered CR8EIA-10's as that's what the factory plug is, but when I pulled the old plug out it was a CR8EIB-10. No biggie I thought. Until I pulled the A-10 out of the box and saw it appeared to be "without a top". The top looks threaded, like many of you may know, instead of having a knob for the plug cap to snug or pop over. (images below) Of course I wonder how could my plug cap snap onto this new top when the B-10 top is much larger? I tried it out and the plug cap fits loose on the top. Of course there is the retainer bracket that holds the plug cap and keeps it from coming out of the engine, but WTF??  

Does my bike have the incorrect coil assembly and plug cap on it or did I not push it onto the new plug well enough? Any help would be greatly appreciated.

Edited March 30, 2017 by Bolt Speedman

[nucular]

I'm not familiar with these particular plugs but can you unscrew the top from your old plug and put it on the new one? Any plug I have ever bought that was similar to the B plug pictured above just had a threaded on cap.

[BOLT SPEEDMAN]

I gently tried that last night but the top wouldn't come off of the B-10 plug without applying force that could damage the head of it, and I didn't want to mangle a plug that I might have to use this weekend.  :\ 

[nucular]

Have an old plug laying around that has a removable one?

[BOLT SPEEDMAN]

I will check when I get home this evening. I would mainly like to know if anyone knows the why? I'm sure they don't sell the A-10s the way they are so you can screw your own top on. I've also read threads about people having the opposite problem: Having an A-10 in their bike, buying a B-10 and it not fitting into their plug cap because it's too big. I would really like to know if there is a difference in plug cap and coil assemblies between years models, like 12-13 or 13-14? It's really got me scratching my head. 

[BOLT SPEEDMAN]

2 hours ago, nucular said:

Have an old plug laying around that has a removable one?

@nucular I was able to dig a plug up that had a removable top that screwed right onto the new CR8EIA-10. I didn't have time on the lunch break to fire her up but I imagine it should work fine. I just wonder what the difference is in plug caps between those that fit standard plug tops and those that just fit the threaded tops. As in, is it a model variance or aftermarket versus stock?

[nucular]

Probably model variance if I had to guess