What a difference a set of plugs can make

Discussion in 'GS Boxers' started by roadapple, Sep 18, 2013.

  1. roadapple

    roadapple Curve carver

    Joined:
    Nov 28, 2005
    Oddometer:
    146
    Location:
    Central Ohio
    I replaced my original OEM Bosch plugs on my 06 R12GS last week along with a new air cleaner element. The bike has 23k miles on it (yeah, I hear the boos and hisses) -- I have two bikes that get equal time. Before doing the change, I didn't think the bike was running as good as it should -- not bad I thought, but not idling as smoothly as I remembered and maybe a bit more sluggish on acceleration. After I browsed some spark plug threads, I decided to try the NGK DCPR8EIX iridiums. Supposedly the OEM plugs are made to last a long time and supposedly 23K miles is within their lifespan. The OEM's looked pretty good coming out -- a light toasty tan color. Long story short, I'm amazed at the difference in the way the bike runs now. I honestly don't think the bike has performed as well even when it was new -- the idle is flawless and the acceleration is more brisk. Maybe new OEM plugs would have made the same difference -- who knows? What I do know is that I'll be changing plugs more often in the future. The iridiums need changing more often but it's a small price to pay for such a noticeable difference.
    #1
  2. STUFF2C

    STUFF2C We Ain't Left Yet!!

    Joined:
    Aug 12, 2004
    Oddometer:
    3,210
    Location:
    O-lando
    Maybe after 50k miles I need to consider changing mine. thanks for the tip!n reminder:lol3
    #2
  3. genka

    genka SUV hater

    Joined:
    Mar 25, 2010
    Oddometer:
    1,671
    Location:
    Baltimore, MD
    I replaced mine at about 40k, and didn't notice any difference. Regular spark plug maintenance was very important on the old bikes with points ignition. Modern electronic ignition systems can compensate for wider gap or fouled electrodes. You probably experience a placebo effect.
    #3
  4. JetSpeed

    JetSpeed Naviator

    Joined:
    Nov 28, 2007
    Oddometer:
    6,745
    Location:
    Coronado, CA - KNZY
    I had never specifically looked into how long Iridium spark plugs last until I read this, I had just assumed that they last about as long (or longer) as Platinum plugs which is around 100k miles in automotive applications.
    Found out that isn't necessarily the case, some Iridium plugs are designed to last over 100k miles and others just 30 thousand, which would be much less in the GS motor.
    Thanks for that.
    #4
  5. def

    def Ginger th wonder dog

    Joined:
    Feb 28, 2004
    Oddometer:
    13,591
    Location:
    The woods and mountains of Alabama
    Maybe some of the improvement was the filter?
    #5
  6. johnd04

    johnd04 Been here awhile

    Joined:
    May 3, 2004
    Oddometer:
    264
    Location:
    Burlington, Vermont
    Where do people buy their plugs?
    #6
  7. JetSpeed

    JetSpeed Naviator

    Joined:
    Nov 28, 2007
    Oddometer:
    6,745
    Location:
    Coronado, CA - KNZY

    Same place they buy everything else:
    Costco or Ebay.
    #7
  8. roadapple

    roadapple Curve carver

    Joined:
    Nov 28, 2005
    Oddometer:
    146
    Location:
    Central Ohio
    Could have been, unfortunately not a controlled test. I bought the plugs on ebay, one of the least expensive listings with buy it now -- $7.50 each including shipping.
    #8
  9. roadapple

    roadapple Curve carver

    Joined:
    Nov 28, 2005
    Oddometer:
    146
    Location:
    Central Ohio
    No. Definitely not placebo effect, the bike is running noticeably better. But as stated, the new air filter may be the reason -- or a combination of the two.
    #9
  10. def

    def Ginger th wonder dog

    Joined:
    Feb 28, 2004
    Oddometer:
    13,591
    Location:
    The woods and mountains of Alabama
    Why don't you re-install the old plugs and see what happens. Spark plugs are like oil...most of us change waaaaaaay too often and then imagine some miraculous performance gain. Me? I have never seen any gain other than easier starting when installing new spark plugs.

    As for oil, the only thing I ever saw from an oil change was my lawn mower sounded a bit quieter after I put the used Mobil1 15w-50 from my boxer into it.
    #10
  11. Gruesome

    Gruesome Alter Heizer

    Joined:
    Apr 28, 2007
    Oddometer:
    1,234
    Location:
    Chicago
    From what I know, modern electronic ignition vehicles don't use up spark plugs unless something's wrong with them. My Nissan Altima ran just fine on its first set of spark plugs for 300,000 miles. Never got a valve adjustment either. I did change the oil though every 5,000 to 7,500 miles.
    #11
  12. roadapple

    roadapple Curve carver

    Joined:
    Nov 28, 2005
    Oddometer:
    146
    Location:
    Central Ohio
    Yes, that would be the way to check it out, but I've got waaaaaaaay too many irons in the fire to reinstall old plugs and air cleaner separately and repeat with new ones. All I know for sure is the bike is running better and I'm happy with that. It's also possible that just one of my old plugs may have had a problem.
    #12
  13. NinjaRider

    NinjaRider Been here awhile

    Joined:
    Feb 11, 2007
    Oddometer:
    134
    Location:
    Southern N.H.
    Just changed the plugs on my '08 GSA. The bike has just under 69K on it and
    the plugs about 23.5K miles.

    I wasn't in any hurry to change out the plugs, but the bike seemed to be
    a bit down on top-end power and the idle was a little rough. I had just
    checked the valves, rocker arm clearances and balanced the TBs at 66K,
    so I didn't think those were the culprits.

    I ordered a new set of plugs ( NGK DCPR8EKP ) and installed them. These are
    the same plugs I had in the bike. The electrodes on the old plugs looked
    somewhat worn and the left secondary plug looked darker brown than the
    other three plugs and slightly oily when I removed it. After replacing all the
    plugs and connecting the wires, I ran the engine with one plug disconnected
    at a time and all 4 seemed to be firing.

    Like ROADAPPLE, I noticed an immediate smoother idle and a noticeable
    power difference. The shifting has also been smoother. I am riding down to
    TN from NH and back ( two-up ) at the end of the week. At this point, I think
    the plug change is going to pay off.
    #13
  14. JetSpeed

    JetSpeed Naviator

    Joined:
    Nov 28, 2007
    Oddometer:
    6,745
    Location:
    Coronado, CA - KNZY

    No way!
    You can see from the previous posts that it's a waste of time to change your engine oil or spark plugs.
    It's got to be all in your head.
    #14
  15. Gruesome

    Gruesome Alter Heizer

    Joined:
    Apr 28, 2007
    Oddometer:
    1,234
    Location:
    Chicago
    ...but it's never too late to brush up on your reading skills.
    I said I did change my oil.

    BMWs probably also need valve adjustment once in a while. For the Nissan on the other hand there is no factory specified valve adjustment interval.
    #15
  16. KoolBreeze

    KoolBreeze Been here awhile

    Joined:
    Jan 21, 2007
    Oddometer:
    608
    Location:
    lower west side USofA
    Some people wouldn't notice much of a difference in MANY THINGS while others imagine differences. and while I can't say there was or was not in a variety of instances... I noticed a difference when changing spark plugs in mine, as I also have when performing valve adjustments. so far no real noticeable changes for oil. transmission fluid, slightly... and not really for the better, just "different".

    but yea... back to topic. spark plugs can make a difference. those that say other wise, eh don't bother changing yours then. save a buck and buy a sixer, enjoy.

    :1drink
    #16
  17. Disco Dean

    Disco Dean Long timer

    Joined:
    Jul 17, 2007
    Oddometer:
    1,386
    Location:
    The Great White North
    Plugs are cheap and easy on a gs. Also a good excuse to look around. Each time a plug sparks it wears out a bit so it will run better. How much???? Who knows. But for my money a new set of plugs each year is a no brainier. I put 30k a year on.
    #17
  18. JetSpeed

    JetSpeed Naviator

    Joined:
    Nov 28, 2007
    Oddometer:
    6,745
    Location:
    Coronado, CA - KNZY
    I wasn't talking about your post, maybe you should take some of your own advice and try reading the post by def.
    #18
  19. Mr. Canoehead

    Mr. Canoehead Taste Gunnels!

    Joined:
    Apr 16, 2007
    Oddometer:
    2,198
    Location:
    Calgary, Too far to the mountains and too cold
    One reason to change the plugs is that they get corroded and then the damn stick coils stick (no pun intended). I had a hell of a time getting my coils out (even using the handy BMW tool) this weekend and I'll be pulling the coils and re-greasing them annually from now on.
    #19
  20. def

    def Ginger th wonder dog

    Joined:
    Feb 28, 2004
    Oddometer:
    13,591
    Location:
    The woods and mountains of Alabama
    #20