ralfyguy wrote on 10/27/08 at 06:29:52:

Upper 20's        

Chart says -10 C or -14 F , so you  are within the limits,  but  getting real close.

I have 20W-50 Mobil 1 in mine.  I also have an oil pressure gauge.  Last week I went on a Charity ride and it was 32 F.  At start-up, the oil pressure came up in about same amount of time.  It was running a little high and took a little longer to get down to a level where I could ride and not peg the gauge.

T Mack

  That should be ok,Its not going to hurt anything

Cold starts and oil thickness are a matter of opinion and temperature.  I run 5w40 Rotella full synthetic now as it gets moving quickly and easily when the bike first starts up, getting up to the cam bearings and keeping everything slipping nicely and not grinding.

The synthetic oil really doesn't change thickness much as it warms up -- the weight it presents once warmed up is pretty much the same as it is cold.  The old SAE standard for oil thickness however was based on single weight dino oils way back at the start of the century and they thinned out considerably between cold mornings and a warmed up engine (driving the need for multi weight dino oils that were developed in the 50s & 60s).  New synthetics are much better oils ....

So, with Rotella 5w40 synthetic I crank with a very mobile easy to move oil and once warmed up good I have "running weight oil" -- actually these are actually the same thickness all the time and that suits me just fine.  The bike acts like it is warming up quicker than it did with thicker dino oils which is also a good thing on these colder mornings.

Rotella is good oil, lots of them good diesel additives to keep your tappets and cam chain happy.

That has almost nothing to do with "pressure" anymore. To me it's a miracle, that not more engines die from that.

OOPS, noticed I didn't answer all of your questions,   My oil pressure gauge is 60 psig.    

At the 40 deg F outside temp's the start-up pressure is around 40 psig.  A rev to around 2000 rpms will take to 60 psig.  

So the concern at cold temps (bitter cold for you southerners)  is too thick an oil and the pump not being able to push it up to the head.  Or in my case too high a pressure popping the tube off the oil presssure line (NOTE: "trust me", remember to tighten the hose clamps on the test port fitting before rev'ing a cold engine after installing stuff....  and the answer is 5 feet  & about a pint ...   ).

Now, in the 30 to 40 deg F range,  most oils are fairly viscous so at 40 psig it will easily get to the head & cam.   NO worries.  If you where in Barrow Alaska , 20W-50 or 10W-40 might be a different story....

IMO I would not use 20W50 if temps are getting that low. I would go with 10W40 which according to the owners manual is good for -4 degrees F to 104+ degrees. I run Amsoil MCF 10W40 Synthetic http://www.lubedealer.com/1lube/FeaturedProductsView.aspx and I live in central Florida where temps seldom dip to freezing but often rise into the high 90s. I have total faith in Amsoil synthetics and realise that synthetics cool internal engine parts and dissipate heat much better than crude oil.
    Rotella is a good lubricant but it is made for diesels and our motorcycles have at least one mechanical design that diesels dont. The transmission and the engine share the same oil. Amsoil MCF has the same additives to prevent cam and camchain wear but also has anti-shear additives and actually carries a GL1 gear lube rating.

                                         Gazoo www.lubedealer.com/1lube  

Bill, I am not sure to be honest. I have never heard of Klotz until the last year. Maybe they just like to pick on the big guys. I am not saying it isnt a good lubricant. We are a small company too. I will try to find out and get back to you. Gazoo www.lubedealer.com/1lube