jhall
BMWMOA #24809
I went to the archives, and found only 2010 and later are available. But I did find the attached, 1981 piece, written by Tom Cutter, which speaks to the ping/detonation/knock/pre-ignition (or whatever else we wanna call it) issues I described, and dual plugging as the fix. Read and enjoy, pay particular attention to pages 4-8. http://www.rubberchickenracinggarage.com/Downloads/TomCutterDualPlugIgnition.pdfYou mention that Nikasil was the answer. I'm curious...how was that a magic bullet? Is the elimination of the iron cylinder as sort of a blanket around the combustion what you're getting at? I do understand that the Nikasil bikes...as well as the Siebenrock top end kit I installed on my /7...should run a bit cooler. But there were other things going on with the 1981 models besides just the change in cylinders.
In the June 1998 Owners News, there was an index of articles. I checked that index and I don't find very much about pinging. I did find this entry:
Engine detonation 7.74.11, 1.76.15, 6.79.20, 7.79.13, 11.82.14, 1.83.12.18, 2.83.8
where x.yy.zz is x=month, yy=year, and zz=page. I only go back to the 1980s and haven't had the chance to look at those articles. But detonation and pinging are not the same, so I'm not sure what to say about the pinging issues you mention. My /7 must have been small valves...but that was never an issue. My Dad had a 1981 R100RT and I don't recall him mentioning pinging issues with his bike.
Here's the index listing for dual plugging:
Dual plugs 11.80.18, 12.80.20, 3.81.18, 5.81.28, 10.85.20, 6.87.71, 4.94.55 (hotter plug on bottom), 6.94.68.69
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