5W-40 or 10W-60 for 2007 1100?

Here is a really basic question which I should know myself - but I don't.  I wanted to top up my bike with a tiny bit of engine oil,  and I was sure that I had read somewhere that the bike needed 10W-60.  Just to be certain before I drove off to the local motorbike-store I re-read my (hardcopy) manual and to my surprise it says to use 5W-40.  I then checked the GRiSO 1100 Workshop Manual which also says to use 5W-40.  Then I found that 2007 Owner's Manual advises 10W-60.  Now what?    (or does it not make any difference?)

Owner's Manual 2006:

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Owner's Manual 2007:

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Workshop Manual:

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Bioman how cold is it where you are? Unless you ride the Arctic Circle , and lookin at your location you bloody well may, or some other similar climate the 10W60 is the stuff to use. Here in Australia we are blessed both with the climate and with an Australian oil company that makes damn good stuff. Penrite ten tenths premium 10w60 fully synth. I use this in both my 1100 and 1200. Youd reckon the factory would have a temperature /viscosity chart in the manuals Can you ask the Importer? What does the web site of your oil manufacturer say ? Cheers

Thanks Charlie. I'll go for the 10W60 then (as I try to stay away from the Arctic Circle as much as possible).  
That is, if I can find the stuff: my nearest local motorbike dealer (Honda/KTM) didn't have it and (as usual) was not too eager to try to get it.  I will order it online.

Unlike the 1200's the 1100's aren't very fussy. Just use a high quality full synthetic and don't fill it over half way up the stick. As Charlie says a good 10/60 is fine but don't die in a ditch over it.

Pete

Thanks Pete!  

This morning I called my MG dealer in Chilliwack and they will ship the right stuff today for a very reasonable price. Excellent service!

As you've discovered: Italian documentation is more of an advisory concept than a reference source.
Kinda like their traffic signs.....

You probably already know this, but look at the listed fastener torque values sideways as well, and double-check them on here, or elsewhere.

I think this is what they mean by 'character'.

jeremyb wrote:

As you've discovered: Italian documentation is more of an advisory concept than a reference source.
Kinda like their traffic signs.....

You probably already know this, but look at the listed fastener torque values sideways as well, and double-check them on here, or elsewhere.

I think this is what they mean by 'character'.

i think its what you would call... fucking stupid............

why would the 1100 be less fussy as to its oil Pete? valve train ?

Yes, pushrod and tappet system used on the 1100 has been around for ever but the major consideration is the cooling function. The oil that passes through the galleries around the exhaust valves and is fired up under the piston crowns will get bloody hot, really bloody hot! Lower quality oils won't take the heat.

It's one of the 8V ironies. While they are generally grossly over-cooled the oil in certain parts of the engine is pushed to the limits of its endurance.

Pete

10w60, SG rated.
The SG is and "old" specification but seems to be important for Guzzi engine longevity.

hi...your questions have just one solution: GRiSO 1100 needed 10W-60 (motul is the best).
the manual is different because it's OLD. 10W-60 it s the specification that MOTO GUZZI it self gives to the official store right now!! ( i m sure about this from dealers who write in other italian web site)

see ya

My red 06 1100 goes very well on 10w 60 fully synthetic.
That's what I was told to pop in it.
Caoi

Thats the gear Wardy

The difference in operational use between 5W and 10W is probably a mute point given 10W is spec'd to crank (CCS test)at -25C and pump (MRV TP-1) at -30C. The higher the high end spec, the better the high temperature KV and high temperature/high shear viscosity (HTHS is important in cam area !) - hence SAE 60 gives very good protection at normal operating condition. But to get down to 5W from 10W with same additive package ie varnish/deposit/wear protection you need to put in lighter base oils & directionally more volatile light ends that end up back in the inlet system (google NOACK). Another interesting angle is that for the same additive package a 5W40 oil will have to contain more viscosity modifier (that's rubber/polymer to me or you) compared to a 10W40 oil. In general polymer molecules will shear under stress - especially in multi-plate clutches & integrated gearboxes - so a 5W40 is more prone to lose high temperature viscosity over time/life.....

Thanks everybody, for your insight and knowledge! 10W60 is the correct answer indeed. My MG dealer has sent me a bottle of the finest: the real Agip/Eni. GRiSO loves it!

Guzzi shop in my neck of the woods often uses Mobil-1 20W-50. It's much easier to find, anyway.