The book says Yamalube 4 10W30 or 20W40, but no mention of type. Yam do mineral, semi-synth & full synth. and unfortunately, their prices are rather "imaginative".

Yam don't make oils, so what are their oils exactly?

I know about avoiding many car oils, because of friction reducing additives & clutch slip, but my local dealer said he recently serviced a VS 1100 for a customer, used their stock, branded  motorcycle specific oil (don't remember the brand) and the customer came back complaining of clutch slip. In my previous 2 machines, Suzuki Katana 650 and Bonneville 850, I used Unipart semi-synth and had no problems, but the clutch slip phenomena seems to be a trait of V Stars & Viragos as I understand things.

Advice from long term V Star owners appreciated.

I've had Halfords semi-synth in my bike for last 8 years - no slip here.

Considering how low stress a big twin is, chip fat would probably be ok.

As long as its motorcycle chip fat your fine.

In one of my dim(er) past mechanical decisions I used car oil acquired from the back of my dads garage in my old 350, as usual, because I was skint. The clutch was never properly reliable until I swapped out the whole pack, both cork and metal plates, but that was over 20years ago, gulp!

Another vote for Hellfrauds own semi-skimmed here. Had it in a variety of bikes over many years with no problems.

Never had any slip on my Virago, always used Silkolene Super 44 10W40

I use motul 5000 semi  10w40.  I chose this for last services because is coming with k&n filter and for 30 pounds I think is ok. anyway, just don`t use full synthetic oil. yamalube cost a lot of  money and is the same oil.

I've actually used fully synth Silkolene for v twins (now unfortunately discontinued) for the past 5 years. No probs. I've a write up of it somewhere on the forums. Will switch to the standard Silkolene fully synth 10w40 next oil change. I just like the smoothness a fully synth oil imparts to the engine and gear changes.  

Full synthetic 10w50 for me. Was using 20w50 until availability became an issue.

On 3/8/2016 at 1:41 PM, Derekm said:

The book says Yamalube 4 10W30 or 20W40, but no mention of type. Yam do mineral, semi-synth & full synth. and unfortunately, their prices are rather "imaginative".

Yam don't make oils, so what are their oils exactly?

I know about avoiding many car oils, because of friction reducing additives & clutch slip, but my local dealer said he recently serviced a VS 1100 for a customer, used their stock, branded  motorcycle specific oil (don't remember the brand) and the customer came back complaining of clutch slip. In my previous 2 machines, Suzuki Katana 650 and Bonneville 850, I used Unipart semi-synth and had no problems, but the clutch slip phenomena seems to be a trait of V Stars & Viragos as I understand things.

Advice from long term V Star owners appreciated.

Fit a Barnett clutch conversion and you will never have clutch slip again, it replaces the feeble pressure plate with a multi spring clutch. 

You must choose in weather specific scope.
80% percent of people says - 10w40 is better oil for V-Twin, but in my region in sunny days +30C and this oil too liquid for that engine.
As a result, my transmission sounds like a bag of bones... terrible sound.
Please, look at the temperature table and choose oil for your region.