At risk of being admonished here for not properly maintaining my Airhead, will post this. I already posted it on Facebook's 'BMW Airheads', but will put it here also, since not everyone is on FB: Just gotta brag about the minimal valve recession on my current 1995 R100RT Classic. I am aware of BMW's factory suggested maintenance intervals, including 5000 mile valve adjustments. But after 275,000 miles on six different Airheads since 1981, I can discern when the valves need adjusting. Since this RT did not display any symptoms of closing valves since the last adjustment, last year, I continued to ride it just to see how far it would go. But after 11,400 miles, symptoms never did present, so yesterday I checked them anyway. To my dismay all four were EXACTLY as I had set them before. I also checked rocker arm end play, and all were .002" to .003". So I installed new plugs and buttoned it back up, and plan to check the valves again in another 10,000 miles. This mono shock, by far, has the least exhaust valve recession of any Airhead I've owned (76 R90/6, 78 R100/7, 79 R65, 79 R100RT, 82 R100RT). The 79 and 82 RTs were the worst, at only 2000-3000 miles before exhaust valves would hammer themselves closed (even after sending them to Ron Long). The other three would easily go the factory specified 5000 miles between adjustments. This mono shock reminds me of checking my Goldwing's valves after 95,000, which were all within spec. No reason BMW could not get it right either, and they finally did.
I bought this RT about 30 months ago, at 25,000 miles and it now has 70,000. So far, I have enjoyed very mile and hoping for many more trouble free miles to come.
Congrats..... I guess !!
I'd be interested in learning about the fuel and engine oil you're using. Either the valve system is experiencing no wear (I hope) at all, or the valves are recessing at the same rate as the cam face and lifters are wearing.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Thanks for your thoughts.
For gas, whatever 87 octane concoction is at the pump. I do avoid Thornton gas on the east coast, and Arco on the west coast, due to bad experiences decades ago. Otherwise, no brand preference.
For oil, Castrol 20W50 GTX; I prefer GTX Classic with higher zinc content (supposedly), but can't always find it, so sometimes settle for regular GTX. I did find GTX Classic on sale at Walmart last month, $19.95 per 5 quart bottle, so bought several. I also add ZDDP at each oil change, not that I'm aware of scientific proof it does anything, but put in the 'can't hurt' category. The brand I use says 1 bottle treats up to 6 quarts, so I use 1/2 bottle.
I change oil every 5000 miles, and filter every other oil change, at 10,000 miles. Oil consumption is still around 1 pint per 3000 miles. I maintain oil level at about 1/4" below the full mark.
For valve clearances, I set the intakes to snug .006" (.007" is 'no-go' with the gauge), and the exhausts to snug .010" (.011" no-go). I am aware this is .002" above spec, but it's a carryover from days of old with some twin shock Airheads, when the exhaust hammered closed way too soon, so the extra .002" helped extend adjustments a little.
Average RPM, on interstates, is 4250 to 5000 RPM, which is 70-80 MPH. On other roads, probably 3000 to 5000, as I like to use downshift to assist with braking. I usually upshift around 4500-5500 under most any condition.
As mechanics, you and I both know the likelihood of valve recession and cam wear happening at identical rates is almost nonexistent. Goldwing, and even Harley avoided excess recession long ago, so I see no reason why Airheads couldn't do it too, and it appears they finally did with the mono shock's motor. Just sorry it took them so long. This 95 RT is like a breath of fresh air, so I just had to post here and brag about it!
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