10w/40 vs 5w/40 oil??

[Daniel Johnston]

Hello I'm on my second gsxr motorcycle now and I have ran both bikes on 10w/40 grade oil.. I live in the UK so in the winter it's normally an average of 6° degrees when I start my engine.. There is usually that mild tap which I can hear from the top end my 2005 gsxr 600 and my current gen 2 hayabusa do it.. Has anyone used 5w/40 fully synthetic to lubricate the engine better around cold startup?

[dadofthree]

I havent, but imagine in those temps it would be the thing to do

[piratediverjefff]

I run 10w30 now(and have ran 5w30)full synthetic year round,doesn't get cold here(average low in Jan. around 33-35F)but will hit 100F+in Aug.(which I do my best not to get caught out in).You can run 5w30(or 40)without any negative issues.

[jellyrug]

I have been running 5W40 and do oil testing. So far, most of what I have tried gets knocked down to a 5W30 by the gearbox, after about 2,500 miles. I am on Silkolene now Silkolene - Fuchs.. Will be interesting to see if it thins as well after a couple of thousand miles, or if the viscosity polymer holds up.

[Ebusa]

I run 5w-40 Rotella full synthetic all the time no issues so far