My '75 750F rolled over 108,000 miles today. It shifts smoother than ever and is still quiet. I'll be interested to see what the inside of yours looks like.
That's really cool! What kind(s) of oil do you use? Have you had the bike since new?
I've had the bike since July 4, 1977. I bought it with about 3,900 miles on it. I only started keeping maintenance records on it in 1988 when I got it out storage, where it sat for 6 years while I lived in the bush in Alaska. But I remember I used car oil, 10-40 in the winter, and 20-50 in the summer, changing every 1000 miles. I also remember using Belray oil a time or too, as well. My records show I used Pennzoil 1988-1990. I was living in Soldotna at the time, and I think that's what they had at the Pay'N'Save. Then in 1990 at 30,000 miles I started using Castrol, the records show mostly 20-50, changing every 1500 miles or so. In 1994 at 45,000 miles, I started using Honda HP4. I upped the change interval to 2000 miles, then 3000 miles with this oil. In 1998 at 62,000 miles, I started using BMW dino oil, mostly 20-50. I understand that oil is made by Spectro. Change interval with that oil was 3000-4000 for a while, but I do it at 3000 these days. I am still using the BMW oil, but am considering switching because the price has gotten ridiculous lately. It is good oil, though. I change the filter every other oil change. I use either Honda or Fram filters, whatever I have on hand. The bike does not use enough oil between changes to require topping off.
The farthest I've been into the engine was to replace the seals under the cam towers in 2002 at 82,000 miles. At that time, the cam looked good, with no scoring or pitting on the lobes. The rocker shafts had some slight visible wear, but still serviceable. The cam holder and caps had slight visible wear, too. I didn't measure the clearances, just put it back together.
I check the tappet clearances every 3,000 miles. I haven't had to adjust a clearance since 85,000 miles when a couple of them were a thou tight. I've always set the intake at .002 and the exhaust at .003.
This has been the most reliable motorcycle I have been acquainted with, and there's been quite a few. It puts my BMW to shame.
