ZDDP VS CATALYTIC CONVERTOR

[motorbob]

In view of the higher ZDDP anti-wear additives in older oil formulations recommended by BMW (SF or better)what can be the effect of this additive on our catalyst equipped RTs.

[T__]

motorbob, depends on a lot of factors.. If none of the ZDDP additive goes down the tail pipe then no harm no foul.. In real life some does though..

 

I would imagine that just like on automobiles given enough time & enough miles it would have some effect from maybe just a little to maybe a little more..

 

The problem with the ZDDP type additive is that very thing that makes it work so good (coating the metal parts with a protective coating) also coats the catalytic converter element & 02 pallet reducing their efficiency..

 

I can’t speak for BMW engineering but my guess is they just aren’t that concerned with the converter efficiency in long term high mileage usage as they don’t warranty the emission system on motorcycles anywhere near as long as they have to on a modern automobile..

 

I would imagine eventually they (BMW) will become more concerned with oil additives if they have to start warranting the emission system for longer miles or years & it starts costing THEM money to replace emission control parts..

 

 

Twisty

 

[Paul Mihalka]

Does any state in the USA do emission testing on motorcycles like they do on cars? california?

[Harry_Wilshusen]

Not in MO

 

I imagine CA will be first

 

Harry

 

 

 

[motorbob]

Twisty,

Good point about long term. Would the engine run as well with a contaminated catalyst ?

[Joe Frickin' Friday]

Twisty,

Good point about long term. Would the engine run as well with a contaminated catalyst ?

 

Engine will run fine, regardless of cat condition; it'll just put more NOx/CO/HC emissions out the tailpipe. However, the O2 sensor might be contaminated sooner than one would like, and that will affect engine function.

 

Look to high-mileage R1100/R1150/K1200 bikes to see what might happen. The good news is that I haven't heard of many of them with O2 sensor issues.

[Satguy]

I worked at a BMW M/C dealership for a while.

 

We checked several higher mileage R and K bikes with the fancy (and jurassic) BMW GT-1 computer looking to solve driveability problems and never found any with bad O2 sensors.

 

The GT-1 has a function that plots the output of the O2 sensor vs. time on the screen, so you could actually watch in real time what it was doing.

 

I don't recall changing any O2 sensors or cats. with the exception of a couple that were damaged by crashes etc.

[T__]

Bob, with no post cat 02 sensor,, if the cat was just contaminated a little & not actually plugged then no runability problems would be detectable.. I would imagine it would still even pass most state emission inspections as the cat usually still works just not quite as effectively as a new one..

 

Now if the 02 sensor(s) get coated & become lazy then you would see some degradation in engine operation..

 

Remember cats (catalytic converters) have been around a long time & nobody worried about the engine oil additives (ie ZZD content) until fairly recently.. About the time the emission warranty was mandated to a longer duration..

 

The other thing is: most 15w50 or 20w50 engine oil doesn’t fall under the more common requirements for late model automotive emission usage (very few if any late model cars & trucks require 15 or 20w50 engine oil) so those (15/20w50 oil’s) predominately still come with better anti wear additives as their usage isn’t intended for late model emission era cars & trucks..

 

Twisty

 

[92232]

Arizona does. Every year.....not every other year as they do cars.

[motorbob]

Its true that cats have been around for many years when oils had a higher ZDDP content. I never heard of problems.

So I won't worry about it and just keep on riding. Our riding season here in Eastern Canada is just starting.

Thanks for your replies.