My motorcycle is a BMW R65 ´79 . I bought her a couple years ago with 60000 miles and since then I added another 20000. The first year I used mineral oil 20W-50 SG and changed it every 1500 miles (most of them city riding in stop and go conditions). The last year I decided to go with synthetic blend oil specially for motorcycles but I couldn’t find the 20W-50 so I went for 15W-50 SG and I changed it every 2000 miles.
Still I have doubts if this was the best option.
The choice of the synthetic blend was due to the fact that it would be better for the high temperatures of an air-cooled engine in an environment such as Athens – Greece. The fact that it was 15W-50 instead of 20W-50 had the advantage of the oil getting faster to those critical points of the engine at the warming up period where the wear mostly occurs (or I at least that was my impression!).On the other hand this type of oil is to be used in temperatures until 30º and not close to 40º(these high temperatures are quite common here this time of the year).
However the last few months I find myself riding the motorcycle at quite high rpm in hot weather for extended periods of time and I am thinking that it might be worth looking in the market a bit harder for a synthetic blend at 20W-50.
To be a bit more specific the limit of the tacho of my R65 is at 8000rpm and I ride (not always but quite frequent) between 5500 and 6000rpm. I cover around 2000 miles every month or so and half of this mileage is done in the city in slow traffic conditions. Am I killing the engine, or I am worrying without reason? Which interval would you recommend for changing a synthetic blend under these conditions? Would be better to go back to dino oil and keep the changes even more frequent?
Thank you for your patience,
Stavros
Still I have doubts if this was the best option.
The choice of the synthetic blend was due to the fact that it would be better for the high temperatures of an air-cooled engine in an environment such as Athens – Greece. The fact that it was 15W-50 instead of 20W-50 had the advantage of the oil getting faster to those critical points of the engine at the warming up period where the wear mostly occurs (or I at least that was my impression!).On the other hand this type of oil is to be used in temperatures until 30º and not close to 40º(these high temperatures are quite common here this time of the year).
However the last few months I find myself riding the motorcycle at quite high rpm in hot weather for extended periods of time and I am thinking that it might be worth looking in the market a bit harder for a synthetic blend at 20W-50.
To be a bit more specific the limit of the tacho of my R65 is at 8000rpm and I ride (not always but quite frequent) between 5500 and 6000rpm. I cover around 2000 miles every month or so and half of this mileage is done in the city in slow traffic conditions. Am I killing the engine, or I am worrying without reason? Which interval would you recommend for changing a synthetic blend under these conditions? Would be better to go back to dino oil and keep the changes even more frequent?
Thank you for your patience,
Stavros