Modern Buddy

I recently did a 6k mile service on my ss220i and changed the engine oil and CVT oil. At first the bike seemed to run much smoother but then on one of my highway runs(where I run flat out for a good 5-10 miles) the bike acted very strange. It was not getting the speed it normally does and had some stumbling. I think I also saw some smoke. When I arrived at my destination I noticed oil on the back wheel/tire and a couple of drips from the rear of the transmission case.

I had replaced the CVT oil with full synthetic 75W/140 oil(as the manual said to use 140W oil). I asked my dealer about the issue and he said the following:

"Another fine example of why I don’t closely follow the service intervals and recommended fluids... I would suggest a 75-90 gear oil. Redline makes an amazing fluid, but really any 75-90 will work. The 140 is way too thick for practical use. The gear oil is usually stated as a gl-3 fluid, but gl-3 has been superseded by gl-4, and gl-5 as of several years ago. GL-5 is what you will likely find at any auto parts store, and is what we sell and use in our service department. As far as the engine oil, I would recommend any thing from a 5-30 to a 10-40. Synthetic is a cheap upgrade for either, but not necessary."

I will be switching to 75/90 Redline. I hope this helps others...

How much oil did you put in the gearbox? Reason I ask is because your description of the problem sounds like simptoms of an overfilled gearbox.

I put in as much as specified in the manual(110ml). I guess it could be too much?

Well, thats the correct amount. Not sure where the oil on the rear tire is coming from then. 140wt oil does seem kinda thick though. Can't remember what I used.

After you asked I figured it would be worth it to check the amount since it is so easily changed. I used a graduated cylinder this time. The amount which came out? 150ml!!! Way overfilled. Thanks so much for your suggestion. I hope nothing was damaged in the 100 or so miles I have driven it overfilled... The manual does say SAE 85/140. I am using 75/140 and will change to 75/90 when I get it.

There shouldn't be any damage. The excess oil usually just blows out through the vent hole (on to your tire).

Exactly what my mechanic said. Thanks...