Engine oil?
 

I'm sure i was reading a post on here not long ago about which engine oil to use but I can't seem to find it in the search. I've just been looking through the Haynes manual and it says to use fully synthetic oil but I'm sure I've read a few of u guys having problems with the clutch slipping so should I be putting semi synthetic in instead?

I've used both without problems. Use good quality oil. Suggest 50w at the upper end, because its going to get very hot and you'll be warming it up before you race (not like riding it straight out of the garage on a cold morning!)

based on personal experience I stay away from the fully synth oil in my DD bike with its standard style clutch after initially experiencing clutch slip on my 620
opting for Silkolene 15W50

Ok chaps thanks for the advise. I'm sure I will have many more novice questions to come

Used fully synthetic in class B bikes over the past 6 years without problem, but a 620 will slip with it in, so used semi synthetic.


Chris:burn:

I was talking to Neil Spalding the other day about clutches as you know he's Sigma clutches, my question was if you can run an 848 wet clutch on fully synthetic with no slip, why can't you run the same oil in the 620? Simple answer there are less plates in the 620 so less friction area.

I've tried to use fully synthetic several times without success, on the dyno the clutches all start to slip around 60bhp so I use 15/50 semi & change it every meeting.

I know some will say they use fully synth I'm sure they do! They must be very kind on the clutch;)

Good source of oils here:

http://www.smithandallan.com/

they also use Ebay.

Thanks for the replies. I take it 10w40 is no good for racing?

Seems that some full synthetics cause more problems than others. I used Shell Ultra in many DD bikes with no problems. Motul 7100 seems to work ok to. Full synths from silkoline and putoline appears to slip......
A lot can depend on the condition of your clutch to.

i use shell ultra fully synth .. used it in th 800 too

got slip with a standard clutch .. fitted a barnett hd clutch and no slip

i just thought it was the standard clutch not up to it