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Leaded Petrol in bikes

Discussion in 'Technical and Troubleshooting Torque' started by pete the freak, Oct 25, 2005.

  1. Yo dudes,

    Need some help, might be a really dumb question, but afterall what's Netrider for??

    So I got this '85 Yamaha SRX the other day and been having problems getting it to run. After piss-farting around for the better part of a month, we finally got it going on a semi-regular basis. It starts pretty good, stays running pretty good, but it still has some issues.

    Now I'm exploring other avenues like timing and and the air-fuel mixture, but I asked my self the other day:

    "Seeing as though this bike is 20 years old, could it be possible that it's supposed to run on leaded petrol??"

    I've asked my dad and a couple of my biker mates, I've had a scan through what little documentation I could find, and couldn't find anything on the type of petrol. Interestingly, there is no "Unleaded Fuel Only" sticker on the bike, but that could be because it was resprayed privately recently.

    So what do you reckon? Could it be that my new bike needs premium, or am I barking up the wrong tree altogether?
  2. Unlikely that it would need leaded petrol. Japan actually started phasing out leaded petrol in 1970, by the early 80's only 1-2% of fuel sold in the country contained lead. So unless seperate engines were made for export the bike will run on unleaded but it will need to be 95 octane or better since 90 octane fuel (ie standard unleaded) wasn't available when it was released.[/quote]
  3. I think that bike should run unleaded. Most Jap bikes went over in the early 80's.

    If it needs leaded then you need to run 95 octane fuel with a valve lubricant like "Flashlube".

    You may get away with a 98 octane fuel with a lube, but definatly don't run Optimax. Some people on this site don't mind it. But from experience a bike needing leaded fuel will shit itself on Optimax. 7/11 use shell fuel

    Oh and replace your plug.
  4. THanks dudes, looks like it's BP Ultimate all the way then...
  5. I favour the 95's because I think there are less additives. Also BP and Shell are made at the same refinery. I think they blend their high octane stuff differenlty, but others think not.

    Maybe start with Caltex 95 if you are having troubles.
  6. But the BP's only 800m away!!!

    Didn't know BP and Shell shared refineries...
  7. BP do also sell a 95 octane Premium which might be worth a shot. As far as sharing refineries go BP do actually own and operate two of their own at Kwinana and Bulwer Island. They do "trade" fuel with Shell, Mobil and Caltex to reduce transport costs (BP here is sourced from Shell whereas Shell in WA is sourced from BP) however BP ultimate is exclusively sold and manufactured by BP.
  8. Yep until recently there were only two sorces of fuel in all the major cities.

    Shell/BP (Clyde in Sydney)

    Caltex/Ampol (Kurnell in Sydney)

    There is imported fuel coming in these days through PD Van Omeron. Refined from Sour Crude. Don't use it if you find someone selling it. It roots oil and eventually engines
  9. Also:
    Bulwer Island (BP, Brisbane)
    Lytton (Caltex, Brisbane)
    Altona (Mobil, Melbourne)
    Geelong (Shell, Melbourne)
    Port Stanvac (Mobil, Adelaide)
    Kwinana (BP, Perth)
    So some major cities actually only have the one refinery.
  10. Interesting results with Caltex 95 myself

    In the past I always ran BP 95 premium and the S Trip ran pretty well, and then I noticed the Ultimate and started using it exclusivelly until after a few tanks the bike seemed to be running rich and getting very poor fuel economy so I went back to the BP95 or mobil 95 and everything went back to normal.

    That is until a recent 1000km trip when I had to fill with Caltex a couple of times and power response and fuel economy improved dramatically, the exhaust tip is a much better colour as well, not so sooty.

    The only other varience had been the weather, which was warm and sunny while using the Caltex, although with fuel injection i would have thought that this would not have made much of a difference?
  11. the old leaded super was the best fuel for performance motors, it was high octane, it burned clean, and it smelled ok.

    todays fuels even the premium ones are no match for the performance qualities of the old 'super'

    the 80's greenies and politicians killed it and we are worse off for it - performance and health wise.

    the oil companies also favoured the move because additives like benzene cost much less than lead, and they pocketed the difference.

    todays unleaded products are much more toxic with the benzene, toluene, xylene, etc. that need to be added to make it knock free and octane rich.

    vehicles catalytic converters don't work until they reach some 400°, so inhaling any exhust fumes when cold starting a ULP vehicle is way more damaging to health than the old leaded vehicles.

    research shows that the lead in blood comes not from breathing airborne lead but from eating and drinking it - that is, principally from soldered food containers, lead-based paints and lead pipes.

    In Britain, this risk is so clear that the National Society for Clean Air has removed their support for ULP.
  12. The initial reason for adding Tetra-Ethyl Lead (TEL) to petrol instead of other, less toxic compounds, was that TEL was a patented invention of DuPont. By teaming up with General Motors they were able to ensure huge profits from every litre of fuel sold. The World Health organisation has labelled TEL "the biggest mistake of the 20th century" since it accounts for 80-90% of all lead contamination and accounts for 50,000 deaths a year. Performance-wise toluene is actually far more effective than lead (turbo-era F1 cars used to run on a very toluene rich blend and produced some of the highest engine outputs ever - around 1000bhp from 1L engines) however it is carcinogenic.
  13. In the early 1920s, a fellow called Thomas Midgie was looking for something to combine with the free radicals to stop 'knocking'. He found that things like platinum, silver and lead were able to hold these free radicals. Midgie figured that if he could get lead oxide spread through the mixture, sooner or later the free radicals would bump into a bit of lead oxide, which forms lead dioxide, as lead has four bonds, but that breaks down to lead, Pb2, and oxygen, O2, but slowed down the reaction.

    In searching for a way to get the lead spread through the mixture, Midgie found a compound called lead tetraethyl which is similar to the combinations in the groups making up petrol. The first good thing about it is because it is like petrol, it is soluble in petrol. The second is that it vaporises like petrol, which means that the lead tetraethyl is dotted around in the mixture. The third thing: it breaks down to lead at upper cylinder temperatures, lead atoms spread around and the ethyls are let go. Then the lead does its job, combining with the free radicals and slowing down the reaction.

    Midgie's research took the octane number from 50 to 65; then research at the refinery introduced crackling reforming and improved the octane number past 89; then, with further developments and money, they got the octane number up to 110 for aviation fuel.
  14. What about 100LL Avgas? It still contains lead, not as much as the old 'super', but thats what the "LL" stand's for, 'Low Lead'. It's 100 octane, and is refined and stored to higher standards that any car fuel. Since Petrol prices went ballistic I am actually paying less for 100LL in my aircraft, than for PULP in my bike.
  15. yes incitatus avgas is still the real deal, in another life when i was a car nut with more dollars than cents i used to drive out to tullamarine airport and fill with avgas at the servo there. lots of guys who ran high compression highly modded motors used to do it.

  16. Yeah, anything over about 11.5 to 1 comp ratio, and nothing you can buy at a servo will do the job properly.
  17. Yep Midgley (not Midgie) discovered TEL whilst working for General Motors Research, later the Ethyl Gasoline Corporation was formed between GM and DuPont to produce and market TEL. Many of the workers and researchers suffered from lead poisoning (including Midgley) many later died as a result (he was also the man who invented CFCs). Incidentally TEL was only introduced initially as a "bridge" to higher octane fuels using ethanol but there was more money to be made in sticking with lead, indeed engines at the time had to be redesigned to run on leaded fuel and other refineries such as Sunoco and Arco were also sucesfully producing higher octane fuel through catalytic "cracking". There were also a number of other compounds available to reduce knocking, 40 were patented between 1920 and 1930 by GM alone, though most cost more than TEL.
  18. Hey JD, you seem like a gen kiddie on gasoline, I have a question you might know the answer to.

    What fuel available today would most closely approximate the composition of the petrol used in WW1 era Rotary aircraft engines, like the LeRhone and Oberursel?
  19. During that period there was no real standards with petrol, thermal cracking had been invented but most fuel was still derived basically from kerosene and quality varied greatly depending upon supplier. At the time octane ratings didn't exist but fuel produced between 1900-1910 was around 40 octane, 50 octane was obtainable by the start of 1920. To overcome knocking in military engines petrol was usually mixed four:eek:ne with benzol although this had many detrimental effects on the engine. Don't know what would be a modern equivalent, best bet would be to get in touch with a vintage car club, I think many of them run their engines on a mixture of unleaded and kerosene.
  20. Thanks, I'll do that. I do know that Rotary aircraft engines, although 4-stroke, had a 'total loss' oil system that mixed castor oil with the gasoline as it was fed into the cylinders.