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conventional oil from synthetic

wudshp

New member
Is it bad to use conventional BMW oil after the bike has already been using synthetic. What are the ramifications if I already did this?
 
None. Read the labels of your oil bottles some time. You can mix and match synth, semi synth, dead dino juice, all with out issue. In effect what you have done is the same as using a semi-synth --- a blend of natural and synthetic oil.

Edit: I misread your post as asking if it was OK to mix, not change oils. Yeah, mix or change is OK.
 
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synthetic to conventional

I've done it on two bikes with no problem. Since I have to do 10 to 15 oil changes a year ( 3 bikes) I saved some money going back to conventional oil.
 
Engines do not care what kind of oil is being used. Synthetic works better in high temp operations, but as long as you watch the API Service grade required, you will not have problems. You can even mix synthetic and dinosaur oils if necessary. Do not stress over this.
 
If you want to scientifically determine when you can safely change oil, give Blackstone Labs a try:

I notice on their sample results that two tests are not done that I think would be good for considering the health of oil. That is TAN and TBN...total acid number and total base number. If one were to consider this sort of thing, it would make sense to first send in a sample of fresh oil. The fresh oil will show that the TBN is quite high...this is the base additives there to counteract the acids that build up. TAN should be essentially zero. Over time, TBN comes down and TAN goes up. Typically, the oil should be changed, among other indicators, when TBN and TAN equal each other.
 
The only engines I use synthetic in are lawn mower engines. First because I bought a Briggs and Stratton that required it and then because the only engines I ever wore out, rod bearing failure or smoke were mower engines.
What little cooling features they have built in are soon packed with debris making them run hotter.
They run at full throttle.
With the little oil they will hold it doesn't cost much.

My 2 cents.
 
Anybody think any new technology is going into conventional motor oils?

What do you suppose the split is as regards time/resources devoted to research at oil companies? Conventional maybe 20%, synthetic maybe 80%?

Porsche, BMW, and Mercedes and probably others only permit use of synthetics. They, plus Corvette and again probably others come from factory with synthetic. Suppose they're devoting any time to research on use of conventional oils in their products?

How is it possible to fantasize that BMW builds current motorcycles to 1956 standards?

How is it possible to fantasize conventional and synthetic are the same thing and the latter is simply a conspiracy?
 
I notice on their sample results that two tests are not done that I think would be good for considering the health of oil. That is TAN and TBN...total acid number and total base number. If one were to consider this sort of thing, it would make sense to first send in a sample of fresh oil. The fresh oil will show that the TBN is quite high...this is the base additives there to counteract the acids that build up. TAN should be essentially zero. Over time, TBN comes down and TAN goes up. Typically, the oil should be changed, among other indicators, when TBN and TAN equal each other.

TBN/TAN can be requested for a slight extra fee - it's the "extended use" option.. They have been very cooperative with some oddball requests I've asked.. like testing a brand new sample of some BMW specific oil (for M-cars, Castrol TWS 10W-60) to get an idea of the initial properties of the oil (it's good enough that I'm using it in my R1200R.. ZDDP % exceeds BMW motorcycle oil numbers..) They did that test for me for free since they also were interested in the numbers.

Blackstone is a good resource - recommended..
 
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The prepaid service plan I bought my my R1200R recently expired so I did my own oil change. I used full synthetic and the dealer had been using a blend. I could tell an amazing difference in smoothness, quietness, and running temperature. It hurt to spend $64 on 4 liters of Motorex, but it was worth it.

:lurk
 
The prepaid service plan I bought my my R1200R recently expired so I did my own oil change. I used full synthetic and the dealer had been using a blend. I could tell an amazing difference in smoothness, quietness, and running temperature. It hurt to spend $64 on 4 liters of Motorex, but it was worth it.

I've tried synthetic in cars and trucks with V8, V6 and I4 engines as well as an airhead, oilhead and K-bike over a lot of years. I couldn't tell a darn bit of difference except the teen-age airhead and K-bike developed seepage around old and hardened seals. Changing back to conventional oil corrected the seepage problem.
 
The prepaid service plan I bought my my R1200R recently expired so I did my own oil change. I used full synthetic and the dealer had been using a blend. I could tell an amazing difference in smoothness, quietness, and running temperature. It hurt to spend $64 on 4 liters of Motorex, but it was worth it.

"Observer effects are rooted in the universal human tendency to interpret data in a manner consistent with one?s expectations. This tendency is particularly likely to distort the results of a scientific test when the underlying data are ambiguous and the scientist is exposed to domain-irrelevant information that engages emotions or desires"

Isn't that just the cat's meow?
 
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