Is gasohol risk quantifiable? attempt to come to a conclusio

Discussion in 'Technical' started by PICO-PICO, Nov 11, 2009.


    PICO-PICO Ol'Timer

    Is the gasohol risk quantifiable?

    For me dollars and cents speak the ultimate language when it comes to technical product choices.

    Perhaps it is possible to harmonize the discussion through this common denominator.

    Using my 70.000km and the engine running smoothly from the first day as an example=

    Estm. average consumption 6L/100 km= 4200 L total petrol consumption

    Assuming all 4200 L had Gasohol and assuming 3b saving versus non-gasohol the total savings are 25200b.

    This should be correlated to

    - lower life span of the engine expressed in $value.

    ( any empirical studies on this ? )

    - alternatively repair cost caused by gasohol usage ( Shell guaranties any damage )

    - or provable power loss

    Up to this very second my 25200b are indisputable savings, no repair on the engine, no power loss, no indication of a lower life/km expectancy.

    Use your own assumptions and tell the outcome. It might, perhaps might change with higher power bikes.
    If that is the case it should be clearly mentioned to differentiate to normal street bikes

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  3. johngooding

    johngooding Ol'Timer

    I cannot detect any difference in engine performance when running Yamaha FJR, Yamaha FZ1, BMW 1200GS, Ninja 650R on pure benzine or on gashohol. I use 95 Gasohol in the BMW and the FZ1 and 91 gasohol in the other 2. All my bikes are used at least weekly so do not have the problem of the fuel separating out as reported in earlier posts. So for regularly used bikes use the gasohol. If you bike is going to sit for a long time, maybe a good policy to leave it with pure benzine in, switch back to gasohol use when bike back in use again. I know the Captain said it was a waste of money, but his Phantom was OK not used for a few months with gasohol in it. He does not know if he would have had a problem if he had left it for that time with pure benzine. I wonder what he will do at the end of this riding season for storage? If he leaves it with pure benzine in then we will find out in October 2010 what the result is.
    The FJR covered 29,000km in the 19 months I owned it, nearly all on 91 gasohol. No sign of any films or deposits and no deterioration in performance. I am confident it would go on the same way indefinately.

    All the above applies to the newer fuel injected bikes that the manufacturers state are gasohol compliant, not to some older machinery which may well have issues with rubber fuel system components, and to machines that already have some corrosion in fuel tanks, because the alcohol will probably clean up the metal surfaces, so leaving the corrosion to travel around the fuel system and engine. Better in those cases to stick with pure benzine.
    If the above is repetitious, I apologise, but felt a recommendation based on experience of the last 18 months riding, total of nearly 100K on different machines, may be in order.
  4. harrythefinn

    harrythefinn Ol'Timer

    I work a rotation of approx 6 weeks on/off so my bikes sit for 6 weeks not being ridden while I'm at work. The following is what I have noticed :-

    My old VFR800 (2000) fuel injected starts first go after each rest and seems to have no problems with any fuel.

    My XR650 (2000) has a Edelbrock carb and does not start after sitting for 6 weeks with Gasohol. Needs draining of the bowl and usually a cleaning. I sometimes get away with a flush and a couple of sharp knocks on the side of the carb to loosen up whatever is stuck. Parked with straight petrol it either starts first kick or 4/5 kicks.

    My KTM525 (2005) with an electric leg starts after a lot of protest after being parked with gasohol, seems slightly easier with normal fuel, but not a lot of difference.

    My XL600LM (1984)which is usually parked longer between rides goes sticky with any fuel, so needs draining between rides and a carb opening everytime even if left empty.

    All I want is a reliable way to ensure my bikes start each time, is it best to drain the carbs? Do I need an additive like a "winter" storage used in colder climes? Or do I need to do as with my truck just get the missus to start them once a week for 10 minutes? (getting her to kick start the XR650 might take some work!)

    Seems like regular use is the key for newer machines???

    PICO-PICO Ol'Timer

    If the possible risk with gasohol is=

    issues with rubber fuel system components, and to machines that already have some corrosion in fuel tanks, because the alcohol will probably clean up the metal surfaces, so leaving the corrosion to travel around the fuel system and engine.

    1. The question is = what is defined as OLDER BIKES ??

    2. Is the potential monetary loss
    a) the entire engine or
    b) or cost of partial overhauling ???

    Provided Gasohol is the only reason for engine failure and not e.g. normal wear and tear than the answer from
    a) or b)
    is to be correlated to savings from gasohol.

    = does it make economic sense?

    As shown in my comment above for me I does make sense.

    I also assume if there had been serious gasohol problem consumer agencies/group and the press would just devour the oil companies.

  6. johngooding

    johngooding Ol'Timer

    I said 'older 'bikes, because I am not sure when manufacturers started using rubber seals and hoses that were compatible with the alcohol in gasohol. Probably more than 5 or even 10 years old, but thats a guess. The problem is more likely to be found in bikes with carburettors because they have more rubber components, but as the good captain has found out the Phantom is not having problems and Honda have made sure that it is OK with gasohol. It is easy to specify the correct rubber o rings, seals and gaskets which are resistant to the benzine alcohol mix which is gasohol. It is also possible to change 'older' non resistant, o rings and seals with resistant ones. Not to big a job I would have thought, but I have no idea if they are readily available in Thailand.
    Very difficult to quantify the risks, I have limited personal experience with 'older bikes' here in Thailand so I speak from a knowledge of rubber compounding and solvent attack and just common sense.
    The whole engine could not be affected because only the Petrol tank, the pipes to the fuel injection or carburettors, the inlet to the cylinders come into contact with unburnt gasohol. I have never heard of problems with cylinder bores, pistons or valves, or the exhaust system. The whole of the bottom part of the engine and gearbox has no contact with the fuel, and so cannot be affected.

    The petrol tank corrosion issue is not caused by gasohol, it is caused by the high and variable humidity climate in Thailand and by some 'older' bikes spending a long time with little fuel in the tank, while not being used, the parts above the fuel level are the most liable to corrosion. At some point the corrosion will cause problems wether gasohol is used or not, but if its there it is possible that using gasohol will cause the some of the corroded metal to separate from the tank wall and enter the fuel system.
    I have probably not been too much help here, but I think Pico's desire to be able to calculate the possible cost of repair of gasohol damage, and see if less than the saving in purchase price, is just too difficult to quantify.

    PICO-PICO Ol'Timer

    What I was trying to reach with my simplified question is a conclusion on the discussion about =

    Is Gasohol actually damaging???

    If yes, it is damaging how much does it mean in quantifiable cash terms?

    if yes, there is a cash loss how much is offset by savings through gasohol vs pure petrol purchases ?

    The answers may not be conclusive but they imply=

    there is no substantive evidence that the usage of gasohol under normal operating conditions is damaging.

    Is that a fair statement?


  8. johngooding

    johngooding Ol'Timer

    If one added to the statement- to motorcycles that are manufactured or modified for its use. Then I think it is a fair statement.
  9. ianyonok

    ianyonok Ol'Timer

    Just to put my threepence worth in..
    I had some issues with my '71 Triumph Tiger after filling the tank with gasohol; The carb slide kept getting stuck and the fuel lines cracked. However, after later assessment, I see what happened.
    The alcohol content in the gasohol dissolved the old non-compatible tank sealant, I'd put in years ago. This was the gunge in the carb. I think the fuel lines were just too old anyway.
    I have now cleaned the tank out of all the lumps of old sealant, replaced the fuel lines and have not noticed any further issues, without modifying anything. My bike stands for 6 weeks at a time and certainly seems to run well enough on this juice.
    Nobody had heard of gasohol when my bike was made, but Triumphs and other bikes were used for racing, running on alcohol, in those days.
  10. monsterman

    monsterman Ol'Timer

    My wifes Honda rebel is a 1997 model it does not run at all on Gasohol . we have had the carbs converted using Japanese update kit from Honda but every time Gasohol is put in the carb rubbers and O rings disintigrate so the bike only runs on regular 91 or 95.
  11. ray23

    ray23 Ol'Timer

    I was worried about using gasohoil wiht the 800 until I found out the first 60k it was used in it. I have niotced a bit of seepage at the pet cock from the tank.

    I have used it fo 2 K klms now the only thing I have noticed was the ewngine starving for fuel for brief periods, seconds. I will go back to 91 Benezine and see if that changes. That would indicate a clogged filter to me. The Filter is a part of that Pet Cock a far as I can tell.

    I'm using a bit of STP fuel treartement for the next 500 Klms and see if that clears it up.

    As far a power I haven't noticed any difference. Cost won't know until I change that rubber component.
  12. monsterman

    monsterman Ol'Timer

    I have just overhauled my Ducati S4 fuel system incuding cleaning the fuel tank , all filter, pipoes and injectors ,the result is NOTHING wrong!
    Gasohol has not done anything bad to my system over the last 2 years .The bike also runs pretty well on gasohol , sometimes I put expensive non gasohol Shell V power in .

    My wifes Honda Rebel still cant use gasohol but its not as bad a we Doomslayers predicted.
  13. Ian Bungy

    Ian Bungy Ol'Timer

    I Personally Know one Harley Owner who's Fuel System had to be Completely Rebuilt at Ritchie's after using Gasohol, Ask Ritchie if You Don't take My word for it??? Scotty just had to Replace the Fuel Pump in His GS1200 due to Gasohol. You Can ask Him if also if You Like :roll:
    There are Plenty of Similar Reports around but not written on this Forum, No point in Speaking though if You are only Listening with one Ear to the Positive Reports? The Late Simon Grant also Reported that they had Major Problems with Boats due to Gasohol use!!! This Argument has been circulating around this Board for a very long Time with the Same School Boy mentality Result, He said, She Said??? Like the "X-Files"
    "The Truth is out there if You want to Look"
    Talk about the Blind Leading the Blind :shock: "You can lead a Horse to Water but You can't Make it Drink" :wink:
  14. ray23

    ray23 Ol'Timer

    Interesting the guy who I bought the bike from may or may not be remembering correctly. I noticed the problem after three tanks of gasohoil. So this trip I'm going back to benezine and see if I experience it again.

    Problem with reading my situation is the tank sit empty for six weeks. Might be debri in there. I really don''t have time with the local Mechanics to get the tank clean before I start the trip. Maybe I will have time in Chaing Mai should not be more then a one day job. But that can be hard to find here at times. :lol:

    I believe the real question is how to do we convert to using this fuel it's not going away. I have not seen benezine 95 in our area for a very long time.

    I can run on 91 so I can get by, but when is the day we are not going to find that?
  15. johngooding

    johngooding Ol'Timer

    I am sure this thread will live for a long long time and no harm in that.
    What we may be missing is the fact that some fuel stations in Thailand do not have same quality control systems as, say European countries. It is quite possible to have contamination from poorly maintained tankers and storage tanks and pumping systems. Added to that, especially in out of town areas, who knows what may get into the fuel for various, trying to make a living, reasons. Maybe some bad experiences related here could be attributed to the much maligned alcohol, when it could be some dirty fuel?? Just trying a bit of lateral thinking. Could the Ambassador make a polite comment on that thought :D :D :D
  16. monsterman

    monsterman Ol'Timer

    Dirty fuel can be a problem ,I had to replace my fuel filters after a trip to Rayong last year when the bike started running lean due to a suddenly blocked filter ,it was clogged with a gritty black mess it happend about 10km after filling the tank at PTT .

    BUT destroyed rubber components and high water content damage is not caused by dirt ...gasohol can do that .
  17. johngooding

    johngooding Ol'Timer

    I was not thinking of dirt, but other cheaper solvents, chemicals, etc that may be used for tank or hose cleaning, or even from incorrect use of a tanker by Somchai, on a weekend, using it for a friend. Does it happen, I do not know, as I said, just a thought.
  18. ray23

    ray23 Ol'Timer

    Bad fuel is not umcommon here. I added a touch of STP fuel treatment rode about a 100 Klms Saturday problem didn't happen. I was going to change fuel filters but the bike doesn't have inline filters the filter is part of the tank assembly. I believe in the fuel cock itself so not as easy a others I have seen before.

    I would not mind changing the rubber components. But, we are talking about a 12 year old bike, so that might not be an easy task.

    I will talk to the Kawa dealer in Ching Mai this weekend and see if I can get a source of parts from him. Not having much luck with the Udon shop.
  19. brian66

    brian66 Ol'Timer

    Pico’s question was. Will using Gasohol cost more than using straight petrol?
    To answer that would require an intensive and time-consuming survey.
    I think the short answer is, yes, in the long term, using gasohol would cost more than using petrol.
    I know fuel consumption will be higher, maintainance is very likely to be higher and repairs could be an issue over an extended period of time.
    However, you would have taken so long to find out the actual cost difference, the bike would have aged during the survey and been so old therefore, probably sold or traded in for a newer model.
    If we use the 70,000-kilometer figure you have done on your bike, you would have to travel 35,000 kilometers separately using both fuel types and also ensure the motor started each 35,000 kilometers in the same condition so that everything was equal.
    Then compare the quantity of fuel consumed and purchase cost. You would have to do the 70,000 kilometer very quickly as fuel costs are always changing and it would be hard to put an average price over that period that would work fairly to both fuels.
    It is a proven fact that more fuel is required to achieve the same power output when using gasohol than when using petrol.
    10% alcohol is a very small amount; however, it is enough to reduce the total amount of energy produced in the combustion process.
    Therefore, the EFI system will be sending more gasohol to the combustion chamber because you will hold the throttle position open slightly more to achieve the same performance output from idle to maximum revs in comparison to the EFI system using petrol.
    The total cost for fuel would be very close taking into account the slightly lower purchase price of Gasohol but balanced by the higher consumption than using petrol.
    Your motor will wear out no matter what fuel you use. The oil you use and how often you change it, are the biggest controlling factor in the engine doing high kilometers.
    Let’s leave the components that are in contact with the fuel system but are not part of the engine moving parts, out of the total costs for now. The replacement and cost to maintain these components will be obvious and will occur long before the engine needs a rebuild. So every time you buy a part that has failed due to suspected gasohol use, you need to record the cost. You also need to be sure that the part would not have failed in the same way using petrol.
    Petrol and Gasohol do impact your motor in different ways. As has been said before in these posts, fuel in Thailand can be dirty. However, we are trying to find out if using Gasohol will end up costing more than using petrol. Both types of fuel use petrol as the base fuel.
    One at 100% the other at 90% so if it is dirty fuel before mixing with alcohol the dirty fuel is going to impact the motor the same way regardless of the alcohol mixture. Actually, the alcohol will assist in separating the dirt contamination from the petrol. However, it will still be in the fuel system to do its dirty work.
    The only internal engine parts the fuel has a direct impact on, are the piston, cylinder and valves, valve guides.
    The remainder of your motor is lubricated by the oil. The only place the fuel and oil can contaminate each other is in the cylinder bore as the oil is dragged up and down the cylinder and mixed with vaporised fuel on the cylinder wall. The fuel will contaminate the oil this way. For example when you labour your motor, it is receiving fuel but not completely burning it. The abundant unburnt fuel can and will contaminate the oil more quickly.
    As your motor slowly wears out, the piston rings and valve stems/guides will seal less. When the motor is running this reduced seal will allow some of the gases to blow by and enter the crankcase and cam area (rocker cover). These gases will condensate and mix with the oil. This along with fine particles from the metal surfaces the oil lubricates is what turns nice clean oil, black.
    Gasohol fuel contains alcohol. Alcohol has two negatives that will contribute more to the wearing out of the above-mentioned sections of your motor faster than petrol will.
    The first is, alcohol is corrosive and the second is, alcohol absorbs water.
    Alcohol is corrosive because it absorbs water and the water contains oxygen. These components go hand in hand. Think “Rustâ€
  20. monsterman

    monsterman Ol'Timer

    One thing i noticed in my recent trip to the highlands of northern thailand is that when my Ducati was filled with gasohol it ran noticably weaker at altitude in the mountains than on Shell V power the engine laboured even on downhill runs using gasohol.

    strange eh.
  21. brian66

    brian66 Ol'Timer

    I completely agree with you on the oil change period.
    For the post, I suggested a figure that I though was acceptable for the majority.
    I have always thought I was obsessed with my oil changes.
    When I purchase a new bike, I change the oil and filter after only 100 kilometers. This is the period where, wear will occur and contaminate the oil.
    I purposely ride the bike the 100, bring it home and change the oil. Then change the oil and filter again at 500, then 1000 kilometers. and then every time i return to my home from work. the bikes are not used during this period but i know there is condensation inside the engine.
    I use Synthetic oil and I buy it in bulk. I have a fully equipped workshop and I do all my own servicing so the cost is only for oil and filters.
    I do the same with my cars.
    I change the oil in my track bikes after each track day.
    Oil is the cheapest way to keep a motor pristine.
  22. monsterman

    monsterman Ol'Timer

    I use fully synthetic oil either Putoline or Motul or Mobil1 and change oil and filters every 3000-4000kms /2500miles in my Ducatis .
    In Harley Davidsons in Thailand I always use pennzoil gold for diesel Pickups some of my ex HDs have reached 100,000kms with no engine work using this oil.I ran my old 1200 sportster on this oil for 9 years and the new Thai owner has had it 6 years still on same oil the bottom end and gearbox have never been touched its done 139,407kms with 1 rebore.

    PICO-PICO Ol'Timer

    Let's stick to Gasohol please.

    I understand what is being said. However it seem all in the area of feeling that gasohol is not as good. Too many non-gasohol factors may factors in.
    No hard evidence of statistical relevance, individual impressions don't count , sorry.

    I tried to do a clever search on Google
    v ... afe=images

    but the returns overwhelm me and my understanding of the matter at hand.
    Couldn't even get a list of countries using gasohol, I am not a much-searcher.

    Should there not be something really enlightening under .edu or .gov domains?
    With millions of vehicles using gasohol there must be something of scientific quality.
  24. johngooding

    johngooding Ol'Timer

    Pico - Seems to me that various points have been made and as far as the GTRiders go, the information is all on the table, for you to make of it what you will. If you do find some learned institutions presenting papers on this, you are likely to meet the same conflicting information, hashed up in a different way.

    As often heard in Thailand "Its up to you". If it really worries you so much, play safe, pay the extra and do not use Gasohol.

    If saving the Satang is more important, Use 91 Gasohol

    If its somewhere in between. Alternate between Gasohol and pure benzine fill ups, making sure if you are not going to use the bike for a few weeks, that you leave it filled with benzine.

    But for goodness sake, enjoy your riding and do not spend your all time worrying about wether some nasty chemicals are eating away the insides of your bike, leaving it likely to fail or fall apart at any moment.

    PICO-PICO Ol'Timer

    John, I do enjoy my riding and I am not the least worried using gasohol as shown.
    Plus I can afford 91/95 pure any time.
    You missed the point, it's not worrying about anything except the attempt to bring this rather emotional deliberations which divides believers and non-believers into religions to a fruitful conclusion.

    As the issue is not an esoteric one rather one of chemical science plus statistically relevant study would you not agree that some qualified source would have published such findings and can serve as a generally accepted arbitrator?

    Because this forum is not meant to be for endless theoretical highly intellectual deliberations but as a source of practical biker info I think we owe it to the non-scientific reader to come to A CONCLUSION.

    And if there is a risk the risk ought to be quantifiable.
    My suggestions is CASH as common denominator.
    Any suggestion for a better understandable denominator for ordinary bikers?
    Anything which really helps our audience?
  26. johngooding

    johngooding Ol'Timer

    Hi Pico-Pico, I certainly understand the desire for a conclusion, and will be very happy if there is one forthcoming eventually. I agree the total ownership cost of gasohol, non- gasohol is a sensible measure.
    For me on all my bikes, I am running gasohol, and have not yet met any problems or needed any repairs or replacements due to it. I probably will change my bikes every 2 to 3 years for new ones and I believe based on current running, I will not meet any problems in that timescale. So for me its cheaper to use Gasohol and I will continue to do it. Cheers John

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