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Discussion Starter #1
At the risk of starting something that has the possibility to escalate beyond control, I received some interesting results from oil analyzes on my motorcycles. The two R1100S’s was used for 12 months with Castrol GTX 20W50 during which period each covered about 1,400 miles. The BMW 20W50 oil in the K1200LT was 24 months old and covered 2,300 miles. All three engines had lower than average levels of wear indicator metals, the R1100S’s typically below 5ppm, the K1200LT also below 5ppm except Fe (iron) that showed 9ppm. All three engines appear to be in excellent condition. The slightly higher level of iron could be ascribed to the low mileage of the K1200LT (only about 4,000 miles).

The GTX samples both showed twice the calcium content of the BMW oil, 2400ppm vs. 1200ppm. The BMW oil however also had about 500ppm magnesium. Both of these metals are indicators of detergent/dispersant additives, the combined total of the BMW sample which can probably be considered similar although 30% less than that of GTX.

The GTX samples both had about 160ppm of molybdenum, a so-called emergency lubricant for when the oil film fails. The BMW sample showed only 5ppm molybdenum.

The phosphorus and zinc content of the BMW sample were both about 10% lower than the GTX samples.

The above is probably only of academic interest, although the slightly higher levels of calcium, zinc, phosphorus and molybdenum of the GTX samples provides makes me sleep a little easier.

The biggest difference relates to the TBN number and the viscosity. The GTX samples had TBN numbers of 7.9 and 8.0, considerably higher than the 4.3 of the BMW sample which seem to indicate that the GTX still had significantly more usable life left then the BMW oil. Whether the 900 mile/12month difference in service interval had a significant impact on the TBN number is hard to say.

As for viscosity the GTX samples were 14.09 and 15.21 respectively (cSt @ 100oC), whereas the BMW oil was 13.4. The specified range for 20W50 oil is 16.3-21.9cSt. All three oils therefore sheared and lost some viscosity, with the BMW oil doing worst. Again, the longer service interval may have something to do with this.

So, what does this prove? Since I am a firm believer in value for money, these results indicate that I get similar protection from GTX than from the BMW oil, at lower cost. I realize the price difference per oil change is probably only $20, but for three motorcycles this becomes $60, nearly enough to pay for the oil analyzes!

Although I run synthetic oil in my motor vehicles with an oil service interval of typically 7,500 miles, I firmly believe there is no advantage in using synthetic oils in the motorcycles due to the low service intervals. I’ll be running all three motorcycles on GTX for the next 12 months and plan to conduct another round of oil analyzes next year this time.

I’ve also dissected a BMW oil filter with a view of comparing it to the Bosch 72161. From what I’ve seen thus far I’ll be saving even more money, but we’ll have to wait a year to be sure.
 

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Wow, you are into some serious s#%& with this oil business. I just taste it, and if it's too yucky I put in some more Wal Mart reclaimed oil. Seriously though, I have been using Motul full synthetic since 20k on my LT, 65k now, would like to know how that stacks up. It's pretty spendy, but nothin's too good for my baby!
 

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Thank you for posting this info. I use Castrol 20W50 4T because it meets the BMW specs. And it's less than $5 per quart. And I don't have to go to my dealer.

If you go to the Castrol web site you will see that the 4T product retains much of the formulation that the US EPA forced oil manufacturers to remove from their auto oils in order to meet emission standards. Because the qty of oil sold for motorcycles is but a fraction of what they sell for cars they were allowed to keep the additives in place.

Loren
 

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Interesting but only 2,300 miles in 24 months is borderline neglect of a fine machine meant to be ridden. :p
 

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Discussion Starter #5
I totally agree but there are extenuating circumstances. The LT only had 1,900 miles when I bought it over Labor Day weekend this year. It had covered less than 100 miles since it was last serviced in October 2008. However, since Labor Day I've added more than 2,300 miles and plan to further address this situation next year with trips to Charlotte NC and Boise ID!

With the R1100S I decided not to ride when the temperature gets below my age, but with the LT I can go at least 5degF lower without any special clothing! Tomorrow may be the last suitable riding day for 2010 here in Kansas City and I'll make good use of that.
 

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I've been doing oil analysis with my truck and boat for years, and it's been interesting for sure. I've found absolutely no difference in the results with the cheapest or most expensive oils. The synthetics do clearly stand up better to long-term use (10k change interval) as measured by the tests that show the oil's quality at that mileage, but the wear on the motor really doesn't change at all. This is supported by the fact that the head engineer at the oil test facility says the very same thing--his company sees zero difference between oil brand results when it comes to engine wear. For me, that settles the debate completely. I run synthetic (Shell Rotella) for the longer change interval, and nothing more.
 

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andres said:
I totally agree but there are extenuating circumstances. The LT only had 1,900 miles when I bought it over Labor Day weekend this year. It had covered less than 100 miles since it was last serviced in October 2008. However, since Labor Day I've added more than 2,300 miles and plan to further address this situation next year with trips to Charlotte NC and Boise ID!
Great! Will see you in Boise for sure. On your way to Charlotte, if you get close to North AL be sure and stop by.
 
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