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32a Premix Ratio

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  • #46
    There are snags with "R" in competition use:

    Once mixed with fuel the mix must be used within a day or so because it breaks down. Any surplus has to be discarded (or when I was racing back in pre-catalytic converter days, poured into the fuel tank of the campervan...).

    R is also a bit messy, if it leaks anywhere hot it sets like varnish.

    Plus it can corrode an engine if any residues are left while it is being stored.

    Still good stuff though!
    Colin Sparrow


    • #47
      [QUOTE=johnrunnacles;5171]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"!


      John R (ex #461)[/Cheers John - will be a shame that you are not battling with us next year........I am sure Mike will do well with your Hawkstone! R40 is definately the stuff - didn't realise you could also put it in the gearbox though ! - Take care and if you reconsider your retirement - I always have a spare bike at meetings ]


      • #48
        Thanks Kim

        Thanks Kim. I may well take you up on the offer. Looks like I may have to renew my licence, after all, then?
        Take care.
        John R


        • #49
          Petroil Ratios

          If you can find it, in one of the early LL's I described the efforts made by my group of teenage mates back in the late 60's to get round the impecuniousness and Oil costs that affected our Villiers usage. We couldn't afford the "2d squirt from the drum" on the garage forecourts, so tried various things. Mazola pure Corn Oil, Fairy Liquid, etc., I even had a mate who went on holiday, running his BSA A7 on Suds oil from a lathe at work.

          Makes you wince now!

          Ahh the joys of youth..........


          • #50
            Ah, now you're talking Pete. The mention of Mazola or corn oil reminds me of a friend who uses the stuff at a ratio of 4:1! That's one part cooking oil to four parts heating oil, he runs his aged diesel engined car on it and swears by it! The trouble is, that it's getting too popular, 'cos at his local village shop just as soon as the cooking oil shelf is re-stocked it gets emptied very quickly, so he has to be on the ball to keep the tank topped up! All the same, I think I'll pay the extra and get mine at the pumps as usual.


            • #51
              Using domestic heating oil (kerosene) is illegal for road use as it does not have the higher rate of tax that diesel engine road fuel (DERV) has. Even if you run on 100% cooking oil you have to declare it to HMC&R & pay tax. Likewise its illegal to run road vehicles on 'red' tractor diesel (Gas oil)


              • #52
                "He came second in the Hawkstone class this year to Adrian. fact Adrian pushes his hawkstone more than most - and is very reliable - what mix do you use??"

                No secret Kim, R at 25:1 and have done for the last 25years. Whats more it goes in the gearbox and clutch as well! In that time I've siezed on two seperate occasions. The first time was when I reduced an oversize used piston to fit in a worn bore of smaller diameter, I purposely make it a tightish fit, then run it up until it seized, stripped and dressed the high spots off. No bother after that. The second time was in cutting and shutting a Villiers piston to fit the Vale Onslow. Not surprisingly, it seized first time out at Sproxton, remember the mud at that one, again after redressing it's been fine all season since. Now, is that tempting fate


                • #53
                  I gave my Villiers 7E powered beast out for the first time a few weeks ago, supposedly to check the mixture, as I can't run up the road, the neighbours get upset. It has built up transfers in the crankcases, cutaway piston, fairly drastic porting, long inlet manifold, and runs an 1 1/8 concentric carby. After 2 laps of a 2.5km track, the engine tightened. The plug was a mid brown colour- checked earlier. I was running the same mix as my 73 Maico - Silkolene 2T semi-synthetic at 25/1.
                  I pulled the top end, and I had been very slack when fitting the new rings - gap was 5-7 thou, so I assumed that was the problem. Also, the day was hot - 32 selsius. Reading this thread, I have learned if the iron barrel 197 gets very hot in the UK, major heat in Aus.
                  So now I have several options. The oil mix ratio was probably ok, but should I go to a different oil type?
                  I have correctly gapped the rings - the piston showed no signs of scuffing.
                  Go slow on hot days? We have a lot if those.
                  I have some Silkolene Castor & Ester synthetic oil to try next. It is designed for kart racing, but I'll mix it at 20/1, to see how it goes.
                  See what happens.