Oil advice and Recommendation

[Kawazuki]

Old skool engines need old skool oils - reliants are one step away from tractor engines so I'd stick with thick!

[Barneyb]

The only reason I ask is that the oil manufacturers mobil etc for the engine recommend a 10w/30 or 40, only going to 20w/50 in Mediterranean climate. With the added benefit of synthetic having greater high temperature shearing resistance, low temp engine protection and greater detergent capability to prevent sludge. Wondered if people used 20w/50 in the day as very few multigrade synthetics were available. All the best

[Barneyb]

Got some spare engines so I'm going to try millers 10w/40 semi, has zinc,phos for tappets. Will let you know how it goes

[old git]

hi folks i run my classic mini cooper s on classic 20 w 50 she regularly cruses at 90 mph on the M25 NEVER HAD ANY PROBS I have used both millers and coma oils over the years with some engines having run over 10 years with no sign of degradation

[Barneyb]

Have only heard good things about millers classic, reports of coma also being good, if not using high revs and changed regular. I think most classic 20/50 mineral oils are ok if changed regularly, before swarf starts to build up. From research the biggest cause of head trouble on reliant 850s is caused by running with old oil, especially with no4 cylinder . Engines only done 4k so if a semi millers or otherwise keeps the upper cylinder clean I will be happy