Re: Spark Plugs; report on BKR 7 EIX (8)

["Steve Makohin" <wateredg@xxxxxxxxxxxx>]

Hello Ben,

Ben Barkow wrote <dr.ben@xxxxxxxxx>


> Multiple-electrode spark plugs...I'd recommend the Autolite
> plugs or maybe the trick platinums or  iridiums. But for sure,
> not multi-electrode plugs.

I am NOT a mechanic nor an engine tuner. The following info was conveyed to 
me by someone who is a mechanic, and more importantly, who is a skilled 
engine tuner (John Parker of Budd's BMW, and of John Parker Racing fame).

When my '00 and '01 R1100S surged, John explained the following to me:

 o Oilheads are tuned to run lean

 o A centralized spark in *logically* the ideal location

 o Similar issues have been noted in the F series (surging, rough running)

 o In many cases, proper tuning will resolve the issue, but it will
    return as the bike goes out of tune.

 o He has had great success with non-stock spark plugs, specifically...

 o Spark plugs with a projected tip place the ignition source a little
    deeper into the cylinder, and in many cases, this little difference
    can make all the difference in the world.

 o Additionally, Parker experimented with heat ranges and found...

 o There is no "magic bullet" for Oilheads surging and rough running.
    Different models may behave differently, and a solution that works
    for one bike, may not work that well for an apparent twin (same
    model, same year) because of a host of minor variations (such as
    an 02 sensor sending a signal that's a few milivolts off from its
    "twin", etc) that add up to a significant difference.

 o If you're patient, resourceful, skilled, and you have time on
    your hands, then by all means, experiment and have fun. But for guys
    like me, John Parker's "fix" for my bike was well worth it. I believe
    it was something like CAD$130 for the labor, leaving the bike
    with him for the day to experiment with it, and CAD$9 for the
    two spark plugs (cheaper than BMW parts).

- -Steve Makohin
 '01 R1100S/ABS
 Oakville, Ontario, Canada 

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