Warm up different after oil change?

[seedanpaint]

I changed my oil to find that I must have had a little water, from condensation, in my oil. I found foamy marshallowy oil under the filter cap. Since my oil change, my warm up idle speed has changed. Before oil change, I would back off the choke pretty quickly, it would rev up to 4K with full choke after a few seconds, cut back to 1/2 and it would warm up pretty quick. After oil change, full choke revs up to 2K and sits for a while now.

Anybody think of reasons why the warm up has changes, or it is indicative of any problems?

I've ridden all winter, been colder here this year, mornings when I leave for work have been in the 20's and colder. 08, I am stock except for Yosh slip-on and jetting changes.

Any thoughts?
Thanks!
Dan

[mikedabike64]

I switched from rotella to amsoil 1040, on my pregen so I went from 5w to 10w. same thing here also it takes longer for the oil light to initially go back off at full cold.
but after warm up its ok. perhaps thicker oil viscosity at start up is to blame.
old oil loses viscosity and thins out compared to new oil.
also in cold shorter rides the engine "sweats" which might be the cause of the condensation on your cap. you might need to take the long way home

[seedanpaint]

Originally Posted by mike h

I switched from rotella to amsoil 1040, on my pregen so I went from 5w to 10w. same thing here also it takes longer for the oil light to initially go back off at full cold.
but after warm up its ok. perhaps thicker oil viscosity at start up is to blame.
old oil loses viscosity and thins out compared to new oil.
also in cold shorter rides the engine "sweats" which might be the cause of the condensation on your cap. you might need to take the long way home

+1 on the long way home, always try to! If I could get up earlier in the morning, I'd take the long way to work too!

That's kind what I was thinking about viscosity, I'll see what it does as the oil gets older.

Thanks Mike!