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  • #31
    [QUOTE
    Use of excessively oily fuel-oil mixtures was required back in the day, when basic mineral base 2T oils were all that was commonly available, and added oil compensated for the relatively poor performance of the oils then available.

    However today with vastly superior fully synthetic oils being easily available, there is certainly no need to mix at the type of ratios required for old style mineral oils, and as much of the intake charge on a 2T motor goes straight out of the exhaust port, excessive amounts of oil will quickly clog the exhaust system and reduce performance.

    Finally using excessive amounts of oil will not damage a 2T motor, but will mean that the combustion process is less efficient, exhaust ducts get clogged much more quickly, and bikes will simply not run as well as using the correct amount of oil.[/QUOTE]

    Personally I would not drastically reduce oil ratio in Villiers engines (particularly 2 & 4T) musc below manufactureres spec. I personally use 24 to 1 in my 4T. As for carbon formation, with modern mineral 2 stroke oils there is not the carbon build of as with older oils. I have doneseveral 1000 miles & carbon build up in ports is neglegable. Remember oils is cheaper than bearings (and oil seals) and a de-carb if needed) on a 2 stroke is a straight forward process. I use Comma 2 Stroke mineral oil.

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    • #32
      If you are using cheap low spec type 2T oil, then its probably quite a good idea to stick to use of excessively oily fuel-oil mixtures, but not so in the case of modern synthetic oils, whose performance at appropriate mix ratios, far surpasses that of the lower spec oils.

      Lower performance oils must be mixed using considerably more oil, to prevent engine damage, as they simply dont work as well as modern synthetics. Its also worth looking at whether or not the chosen oil is a low smoke type, as these often contain kerosene, which reduces viscosity and mean its a good idea to use more oil.

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      • #33
        2 stroke oils

        Modern synthetic oils may be ok in modern engines designed for them and with positive lubrication. Older engines like the Villiers are not designed for a 'dryer' lubrication & the oil also acts as a coolent. The centre main bearing & seal on the 2T & 4T twins can suffer with low volume synthetic oil. Another factor is that with less oil in the petrol the carb setting & jets will need changing to take effect of the low viscosity. Todays mineral oils are not low tech & are far better than the straight SAE 30 oil in use when Villiers were in production. Finally the cost, synthetic oils are up to twice as expensive as mineral 2 stroke oils so cost wise there is no saving. Most classic bikes see very little mileage these days & are driven at moderate speeds so again no need for synthetic oils. The higher volume of mineral oil also serves to stop corrosion if engine is unused for long periods.
        One more point, on very old 1930's & 40's 2 stroke engines using plain bearings & no seperate oil seals, synthetic oils are definite no no. In fact a high viscosity oil as originally specified by engine manufacturer at a ratio of 16to 1 or less should be used, the oil acts as a seal for crankcase compression

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        • #34
          Many people get confused over 2T oils, and the suggestion that modern synthetic oils are not suitable for use in older motors is a very common misconception!

          Basically synthetic oils work far more effectively than mineral types, and provide much better lubrication and resistance to wear at far leaner fuel-oil ratios.

          However it is quite correct to suggest that high solvent type synthetic oils are perhaps not ideally suited to air-cooled 2T applications, as while they are far superior to low smoke mineral oils, they are not likely to work quite as well as higher viscosity pre-mix specific type synthetics such as Castrol XR77.

          In terms of cost its generally less expensive to run a fully synthetic pre-mix oil at 70:1, than a mineral type at 20:1, and using the better oil will also reduce engine wear, and mean the exhaust stays a lot cleaner.

          At the end of the day though there is probably no real need to use anything other than a cheap mineral oil for road or non serious competition applications, so just as well to stick with whatever you are comfortable with .

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          • #35
            Anglian oil question.

            I have a 1968 Anglian,37A engine. Before i attempt to start it I want to know what 2 stroke oil do you reccomend and what ratio? Dave.:confused

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            • #36
              2 stroke oil

              Non synthetic Comma 2 stroke oil at 25 to 1 Its ideal for all Villiers engines I have been using it in a 4T twin & have covered almost 20000 trouble free miles, no siezures or bearing failures.

              Wilco Direct do 5 litres at £17.99 http://www.wilcodirect.co.uk/index.p...oducts_id=1325
              Last edited by John Wakefield; 13/12/2010, 05:40 PM.

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              • #37
                Oil Premix Query.

                Originally posted by dave View Post
                I have a 1968 Anglian,37A engine. Before i attempt to start it I want to know what 2 stroke oil do you reccomend and what ratio? Dave.:confused
                Hi Dave, and welcome aboard!

                I've moved your post to this thread, as there is extensive advice and information on oils and premix ratios here from members. As you can imagine, there are many different opinions and preferences with regard to mineral or synthetic, different brands, etc. I would recommend reading through all of the posts and at least then you can make an informed choice.

                Congratulations on the aquisition of your Anglian. If you are very new to Greeves I would heartily recommend you consider joining the GRA, as there is loads of help and support available within the club. It's well worth it!

                All the best with your bike, and hope you enjoy the forum!

                Brian.

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                • #38
                  There will be a piece in the next Leading Link (Feb 1st) about two-stroke oils. It was lifted (with permission) from the BTSC mag.

                  The writer went through FAQs with the chief chemist of Fuchs oil.

                  The bottom line was that with modern two-stroke oils it doesn't really matter which make or type you use, they can all do the job.

                  Incidentally four-stroke oils are differently formulated and shouldn't be used in two-strokes. It's because they have to last for several million revolutions while two-stroke oil only has to work for a couple.
                  Colin Sparrow

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                  • #39
                    I seem to recall advice from the local Castrol dealer in Nth Queensland back in the 60s that Castrol R for 4strokes, and Castrol M for 2strokes, apparently the M stayed in suspension longer. Smelled different, though, not as good as R. Used at 1/2 pint to the gallon, though for scrambles 1/3 pint was cleaner burning.

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                    • #40
                      Oh yes, "R" is something different again. I used to race my Silverstone Rep using R30 at 25:1 without any lube-related problems.
                      Colin Sparrow

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                      • #41
                        Originally posted by Colin Sparrow View Post
                        Oh yes, "R" is something different again. I used to race my Silverstone Rep using R30 at 25:1 without any lube-related problems.
                        only use R in my scramblers, just love the smell

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                        • #42
                          I'm with you Stormer.....CAstrol R in Scramblers.....The cloud of hazy blue smoke after the start seems to have a great effect on spectators as well - My sister is a Doctor - and when she attended a scramble last season and smelt it she asked if I could bottle the smell so she could prescribe it to her patients

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                          • #43
                            Originally posted by Kim275 View Post
                            I'm with you Stormer.....CAstrol R in Scramblers.....The cloud of hazy blue smoke after the start seems to have a great effect on spectators as well - My sister is a Doctor - and when she attended a scramble last season and smelt it she asked if I could bottle the smell so she could prescribe it to her patients
                            Her patients are more than welcome to visit my shed and I would only be to pleased to start a bike for a quick fix, I mean smell

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                            • #44
                              Cheers stormer - will pass it on

                              On a serious note - and this is in relation to motocross - where the engine is tuned and pushed to the limit (at times ) - I would be very careful on running leaner mixes - even with synthetics.

                              Most modern motocross bikes will run on up to 50:1 - but riders generally use 33:1 and compensate with octane booster. These are engines with nicosil plated alloy barrells.....way different from our bikes. For our cast iron liners/alloy barrels I personally would not go leaner than 25:1. .. And 20:1 for an iron barrel - which gets v hot... . The advantage of Castrol R is that it polishes the iron liner - reduces friction. A racing mate in the Greeves series always used modern synthetic for his first 3 seasons and had lots of trouble seizing rings and pistons (and he wasn't running lean petrol/air mix) ----- for the last 3 he has run on Castrol R with no problems. He came second in the Hawkstone class this year to Adrian. ..........in fact Adrian pushes his hawkstone more than most - and is very reliable - what mix do you use??

                              Cheers Kim

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                              • #45
                                R mix

                                As a previous winner of the Hawkstone Class, Kim, (due, incidentally, by far, more to consistent finishing than to finish placings), I can confirm that R is an excellent option for iron-barrel lubrication. The ratio I used was between 20 and 25 to one (certainly never more lean) and my bike has kept its standard bore and undisturbed standard bottom half for five seasons of constant hammering in Dave Harper's Championship series. On Adrian's recommendation, I have used R40 in the gearbox, too, and that has remained sweet throughout.
                                I have just sold the bike to Mike B, so you will have opportunity to check this out with your mate.
                                All best wishes for next season, and with the compliments of "this one"!

                                Regards,

                                John R (ex #461)

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