Quick Q on oil and engine temp.

[Nightster6]

So i changed my oil today, put in Shell Rotella T6 Synthetic 5W-40. Now I got 5W-40 because it was the only one i coulod find in full sythetic at my local Walmart. After changing it, I let it idle in the driveway for bout 5 mins then took it for a spin around the block. When i got back and put it in the garage i noticed the fans were on and it was sitting at 4 bars on the temp gauge. Its 35 degrees outside so im thinkin this is a bit wierd. Is this because i went with too low of a winter viscosity? Any advice if i should leave it or change it to something else?

 

[nicholas.craft]

As for changing it that is up to you? In my opinion I would. The only reason I say that is (I am no mechanic by far) the manual says not to go below a 10w for the first number. I did a bunch of research on here and believe some might run 5W, but I always just follow the manual. Winter I am going to be using 10-40 and summer 20-40.

 

[PhotoAl]

I use that oil and have ridden many times in 35 degree weather - it was 38 today when I rode to work. At those temps the only time I see above 2 bars is when sitting in traffic for a while. I have put over 16,000 miles on my FZ6 in the last two years with Rotella synthetic T6 and am very happy with it. All that said the temp behavior is concerning.

 

[Amorousnerdium]

I changed my oil today to the Rotella T6 as well. Swapped to the SuperTech oil filter also. Pretty much same thing as you, did the oil change, let it run a few minutes, then went for a ride.

However, I seem to gave the opposite results... Previously my temp stayed at four bars consistently. However, after changing over today, my temp stays at about two bars, every so often hitting three. Also noticed that my gear engagement is so much cleaner, no ca-chunk, and the engine even sounded smoother.

Not sure if it was the T6, the SuperTech filter, or both. Went with the T6 because of the reviews I read everywhere about it. Same with the SuperTech, that and it is longer than the stock (ie more filter area) and uses a much better filter medium than stock. So, too many variables there to narrow it down to which one lowered the temp...

Edit - forgot to mention it was closer to 70 degrees here today.

 

[bjorn240]

With all due respect, there's nothing happening here, you were just paying attention to the gauges more than usual.

- Oil viscosity and coolant temperature have effectively nothing to do with one another.
- Coolant temp is modulated by thermostat
- Engines don't reject much heat through the oil
- Lower viscosity oil would actually transfer heat better, not worse
- You've not controlled any variables in your "experiment"
- Dash temp gauges are pretty inexact in any case

Basically, I think the bike got warmer sitting in your driveway and didn't cool down on a short (slow?) trip around the block. If you really think the coolant temp is abnormally high, it has a cause other than different oil -- something like running an extremely lean condition (unlikely), having no oil at all in the motor (unlikely), having a coolant leak, etc. But the oil is not the culprit here.

 

[pchbreeze]

what bjorn said sounds right. see the temp gauge without stop and go traffic to gauge true engine temp relative to ambient temperature.

oil viscosity wont have that significant an effect, to answer your question...not that drastic.

 

[616ah]

I would be more concerned about thin viscosity oil not providing protection you need long term rather than causing an engine temperature problem. Oil that is too thin can't (in my mind) provide the viscosity wedge or cushon in high presure situations (transmission gears) and is more easily squeezed out of bearings under load. Also oils offering a wide range viscosity tend to become even thinner as they wear if I remember correctly...

While synthetic offers fantastic heat resistance qualities and other things - I myself would prefer a "lesser" oil (semi synt, etc) of a correct viscosity.

The temp gauge does rise fairly high before the fan turns on - as other members indicate, what are the chances you didn't get going fast enough or long enough for enough cooling air flow... to cool?

My 2c.

 

[cookies]

i use full synthetic, NO idea of the weight the local yamaha dealership did it for me but i always get about 3 bars, and 4 pretty often too, i see two bars when im on the freeway cruising at about 70mph or so :\ i guess it just depends on how long / fast you are riding. but im pretty sure it's normal.

 

[Razer]

I had this happen when I changed my oil. As soon as the oil filter warmed up and everything was flowing the temp dropped, and the oil light went off.