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  • #16
    In the early days I used to use "R" in my Silverstone. You had to mix the fuel up fresh at the race meeting. Once mixed it was only useable for two days at the most. Any surplus got put in the ancient camper van. Now that smelt nice...

    So no good at all in a road two-stroke.
    Colin Sparrow

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    • #17
      After seemingly trying every combination under the sun, I've ended up at 32:1 and my preference is for Castrol A747.

      My bikes run clean in the sections (cleaner than the rider does!) and are well protected on the road, which is always a worry with the low gearing. Smoke is minimal and oil gunk across the back of the bike is practically non existant.

      The only down side is A747 has castor in it so you need to be a bit cute when swapping over: drain the old stuff out the tank and then run a couple of litres of the new stuff through the engine while pottering about with very few revs on. I appreciate this is o.k for a trials bike but may not work for MX or road racing.

      50:1 was the dumbest thing I ever did (even with an oil that was good for 100:1) as the wear rate seemed to be phenomenally quick, particularly on the big end and mains. It also means rejetting the carb to allow for the extra fuel in the mix and it never ever felt as good as 32:1 does.

      I get to assess all sorts of oils in my day job (motorsport) and I can honestly say that 99% of the time, you get what you pay for: lawnmower or chainsaw oil is exactly that and should never go near a bike engine.

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      • #18
        lawnmower or chainsaw oil is exactly that and should never go near a bike engine.
        I dont agree here Mike I have used Comma 2 stroke http://www.commaoil.com/productsguide/view/6/267/TST5L in my road bike for years no trouble, & that is standard mineral oil marketed for horticultural (lawn mowers & chain saws) as well as motor cycles & scooters. Mind you I use it at 25 : 1 & dont mind a bit of smoke, & oil dripping out of exhaust. Oil is cheaper than bearings!!! In fact Villiers engines always run oily in the exhaust. Comma 2 stroke is available from most motorist discount shops as well as Ernest Doe the agricultural dealers in East Anglia. They are usually a bit cheaper than motor shops. Something about farmers being tight!!
        Last edited by John Wakefield; 27/05/2010, 01:25 PM.

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        • #19
          John - must be because you only ride your bike at lawnmower speed! How far did you get in all those years!!??

          I tend to use a semi-synthetic (Puotline, Silkolene, etc) in my trials bikes at 30:1. In my Yamaha TZ racing bike I use Catrol 747 at 32:1. In the 'old days', I used R30 or 40 at 20:1 in the Yam and 16:1 (yes, half a pint!) in the Silverstone (and it still siezed!).

          I think with oil, it's make your own mind up because everybody seems to have an opinion, some still go with R, some like the modern oils.

          Cheers, Rob

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          • #20
            In 11 years I have covered 19,662 miles on AJH 23C & I ride at between 50 & 60mph (indicated) so you cant say I cosset the bike Rob. The engine is still on the same bottom end believed to be original with 58132 miles on the clock. Apart from normal maintainance & a new set of pistons in the first year. (its still on standard bore) I have done nothing to to the engine. Its running sweeter now than when I bought it. I have used Comma mineral 2 stroke oil at 25:1 all the time I have had the bike. With Comma at around £16 per 5 litre I cant see the poiint of using expensive synthetic oil at over twice the price. Even allowing for the fact that you only use 1/2 the amount of synthetic oil per gallon of petrol it works out dearer. Villiers designed there engines to run on mineral oil at 20:1, but with modern oils this can be increased to 25:1. I have yet to decoke the engine as there is very little deposit in the ports, & until perfomance tails off I leave well alone.
            I appreciate that racing bikes may benefit from synthetic oils, but for roadsters & trials bikes modern mineral oils are fine.
            Last edited by John Wakefield; 30/05/2010, 09:51 AM.

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            • #21
              Premix Oils.

              Just a point. Some time ago, I was talking to a well known Motorcycle Journalist who had rebuilt an elderly Villiers engine and, using the theory of more efficient synthetic oils, reduced the ratio to 30:1. The bike ran awfully, overheated and siezed. He found out by trial and error, that by using basic mineral oil at 16:1 to 20:1 it worked fine. The problem wasn't one of polymer efficiency but of simple fluid thickness. The clearances/carb jets/fling quality of older oils, (as the engine was designed for), at these mixes worked. Older Villiers engines Mk 12s, etc., need even thicker mixes and heavier oils.
              So, run it as designed and leave a blue haze, or try to cut down on smoke but beware engine damage.

              Any help?

              Peter R.

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              • #22
                Very good advice Peter

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                • #23
                  Premix oils and ratios.

                  I reckon his thread has been really useful, and has produced some excellent responses. Many thanks indeed to everyone that has contributed so far.

                  I have learned a great deal personally, and it has been very interesting to hear of everyones experiences and points of view on this topic. We need more threads like this on the forum!!! Thanks to rightsideup for getting the ball rolling.

                  With this in mind I reckon I'll start a new thread on Primary chaincase and Gearbox oils. In the meantime, if anyone has anything else to contribute here, please keep those posts coming! Great stuff!

                  Brian.

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                  • #24
                    "Castrol R" oil, for or against ?

                    Anybody using "Castrol R" oil ?
                    It has been suggested to me to use it in my 1959 Scotish, [mainly I think because of the smell !] However I have read it is not so clean as synthetics so would require more work ie clearing carbon deposits, also it does not mix well with petrol.
                    Andy.

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                    • #25
                      Castrol R

                      Most definitely a No No. Use a straight mineral 2 stroke oil such as Comma Two Stroke at 25 to 1. Castrol R is a racing oil & will gum the engine up. Its old technology now & there are far better racing oils. 1950's/60's trials bikes dont need racing oils

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                      • #26
                        Premix Oils.

                        Originally posted by starman View Post
                        Anybody using "Castrol R" oil ?
                        It has been suggested to me to use it in my 1959 Scotish, [mainly I think because of the smell !] However I have read it is not so clean as synthetics so would require more work ie clearing carbon deposits, also it does not mix well with petrol.
                        Andy.
                        Hi Andy,

                        Have a look at this thread for plenty of info and opinions from members on the pros and cons of oils;

                        Discussion on engines sourced by Greeves from outside firms such as Villiers, British Anzani and Puch. Please use for engine-specific talk only - use the machine subforums for discussions that relate to bikes as a whole.


                        Brian.

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                        • #27
                          Thank's chaps.
                          I will do as you do and keep to mineral.
                          Andy.

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                          • #28
                            Originally posted by starman View Post
                            Anybody using "Castrol R" oil ?
                            We run R40 in all our classic racers and wouldnt use anything else. The formula must have changed because its not as gummy as it once was. And on a racing machine that is regularly cleaned/stripped its not an issue.

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                            • #29
                              RCS. You are using in it its correct application - a racing machine. R is not suitable in trials & road machines.

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                              • #30
                                Originally posted by rightsideup View Post
                                I'm wondering what ratio I should be using in my 1960 Scottish - currently using 30:1 but perhaps could run a little leaner?
                                If you are using the bike for serious competition, then fully synthetic race type oil (something like Castrol XR77) at 70:1 will work very well.For road or trail use then a good semi synthetic at 50:1 is a good idea.

                                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.

                                It is worth stating that for air cooled competition applications, which obviously run hotter than water cooled, it is a good idea to select higher viscosity race type synthetics, which can be safely used at leaner mix ratios, which will provide better response and added power.

                                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.

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