What does the -L stand for in a spark plug code

[reknelb]

On the ngk site it says it means "half heat range". Anyone know what that means?

[Yamahondaman]

HUMMM ??? i do know that the "BP" Plug's are for the "kid's" bike's like the TRI-Zinger,BW-50 , PW-50 and so on FOR THE "PUTTING" around (so they don't foul), but the thing your talking about .... i dunno ... on the other hand if you get a plug that say's B8HS-10 ... That mean's that the GAP is BIGGER ...the "dash" -10 is that the gap is 35-40 instead of .028 thou gap

[kamik333]

If you are asking about NGK, I could not say but with Champion it mean that the threaded portion is 1/2" long. The heat range is how hot the plug burns. In regards to half a heat range, it probably means half an increment...as in low, low and a half, med, med and a half etc...

[reknelb]

so maybe its an 8 and a half plug? dr8es-L

[kamik333]

That sound about right. With NGK, bigger number means colder so that probably means that it is 1/2 a range colder...