spark plug and engine temp

Discussion in 'General Questions' started by coyote888, May 11, 2015.

  1. coyote888

    coyote888 Member

    so i use a champion H10C which (the cart didnt give a specific number) was at the mid range of the hot / cold plug scale. i baught this plug because it was the only thing tractor supply had that fit the bike as the stock plug came broken. the top of the plug is longer but the threaded part is identical to the plug that came with my 48cc. would getting a hear range lower help cool the engine as it runs at aprox 350 at its hottest point in the upper cylinder (after riding WOT), not the head surprisingly. (IR thermometer used so it takes the average temp of about a 1 inch diameter area) if you think it would help at all please name a plug to look for. not just the brand but the actual plug. all the codes on them might as well be Chinese to me. the bike doesnt seem to be running too lean, just pulled the plug and it was a little gray but leaned hard towards being the right color opposed to the whitish too lean color. the needle is raised all the way.

    600ft above sea level. 50-80 ambient temp in the last couple weeks.

    100% stock other than the champion plug.

    i know that was kinda long but i wanted to get all the details in.

  2. Slogger

    Slogger Member

    I got this from somewhere I can't remember, but here's a compatible plug list:

    NGK B6HS, B5HS, B7HS (The 7 would be the coldest)
    Champion L86C
    Champion CJ7Y low profile
    Autolite 425
    ND W2OFS_U
    Bosch W9EO

    I like the NGK plugs best, I've always ran them in all my motorcycles and now my motorbike.
  3. KCvale

    KCvale Motorized Bicycle Vendor

    I put these in all my 2-stroke engines when they come in as a replacement for the stock junk.

    NGK 5955 (BPR7HIX) Iridium spark plug. $8.

    The 7 is the temp rating.
    7 should be good for your location.
    To dissipate more engine heat use a higher number like 8, to keep the engine hotter a lower number like 6.
    Basically run the engine as cold as you can before it starts fouling plugs because it's not hot enough to burn those deposits off.
    Last edited: May 12, 2015
  4. coyote888

    coyote888 Member

    Thanks! I got the NGK b7hs and it's running cooler. Around 320 at a half mile of WOT after a 4 mile ride. Do ring normal riding it hovers around 300. I would like it to be cooler, but it did help ( : thanks
  5. Slogger

    Slogger Member

    You have a ball of fire popping in there. 300 sounds reasonable.
  6. KCvale

    KCvale Motorized Bicycle Vendor

    Throw in an 8 to cool it down even more, has them.