pete_scorpa3 Posted July 7, 2012 Report Share Posted July 7, 2012 ....likely you would have substantially more unburned hydrocarbons from the fuel than you would the oil given that 98% of what goes into the cylinder is gasoline of suspect quality and .... I bought my first trials bike in 1996 and the dealer sold me a can of Catrol TTS, the storeman said stick 80mls in 5 Litres and you'll be ok. Following that exhaustive piece of scientific research, I've used 80mls to 5 litres ever since. Hence (unless I've worked it out wrong,) 62.5:1 ratio. I'm certainkly not saying it's correct, or best, or you shold use it too, just saying what I use. If this is too much oil, I'm prepared to change, for all the reasons discussed in this thread. However, on a slightly different subject that 0007 has touched on in his last post, does anyone have any thoughts on the helath issues of normal pump fuel (petrol/gasoline)? I have concerns that the additives used to replace lead are (possibly) more harmfull than the lead it replaces? A thought to consider; We've all probably been in a wooded gully sat behind a queue of trials bikes breathing in exhaust fumes at some time. All road cars are now fitted with catalytic converters, these work when up to temperature and in good condition. What is happening to the unburnt fuel and other emmisions when it is put through a trials bike? Quote Link to comment Share on other sites More sharing options...
baldilocks Posted July 7, 2012 Report Share Posted July 7, 2012 (edited) I bought my first trials bike in 1996 and the dealer sold me a can of Catrol TTS, the storeman said stick 80mls in 5 Litres and you'll be ok. Following that exhaustive piece of scientific research, I've used 80mls to 5 litres ever since. Hence (unless I've worked it out wrong,) 62.5:1 ratio. I'm certainkly not saying it's correct, or best, or you shold use it too, just saying what I use. If this is too much oil, I'm prepared to change, for all the reasons discussed in this thread. However, on a slightly different subject that 0007 has touched on in his last post, does anyone have any thoughts on the helath issues of normal pump fuel (petrol/gasoline)? I have concerns that the additives used to replace lead are (possibly) more harmfull than the lead it replaces? A thought to consider; We've all probably been in a wooded gully sat behind a queue of trials bikes breathing in exhaust fumes at some time. All road cars are now fitted with catalytic converters, these work when up to temperature and in good condition. What is happening to the unburnt fuel and other emmisions when it is put through a trials bike? good point this is whg stop permitted trials should be banned from a health and safety point of view. Just kidding.... Edited July 7, 2012 by baldilocks Quote Link to comment Share on other sites More sharing options...
pindie Posted July 7, 2012 Report Share Posted July 7, 2012 SSSSSHHHHHH! Don't mention that unless you want to be riding with a catalytic converter weighing lots within the next few years! Quote Link to comment Share on other sites More sharing options...
pete_scorpa3 Posted July 7, 2012 Report Share Posted July 7, 2012 good point this is whg stop permitted trials should be banned from a health and safety point of view. Just kidding.... SSSSSHHHHHH! Don't mention that unless you want to be riding with a catalytic converter weighing lots within the next few years! But seriously, isn't this something that we should all be concerned about? In the 60's and 70's people carried on working with asbestos, then those people became ill in the 90's. Now there are strict controls, that doesn't help those already exposed! Quote Link to comment Share on other sites More sharing options...
pindie Posted July 7, 2012 Report Share Posted July 7, 2012 Stop worrying and get riding. By the time this post is solved oil will have run out! Enjoy burning as much oil and fuel as you can until it's gone. Quote Link to comment Share on other sites More sharing options...
tony27 Posted July 8, 2012 Report Share Posted July 8, 2012 SSSSSHHHHHH! Don't mention that unless you want to be riding with a catalytic converter weighing lots within the next few years! I've got a header pipe for my Jarvis that has never been fitted that contains a catalytic converter from memory, came in the full road kit supplied when I bought the bike new. The main jet fitted for running with the catalytic converter was only around 108 or so from memory so that tells you how much it must restrict exhaust flow Will dig it out & take a photo at some stage Quote Link to comment Share on other sites More sharing options...
copemech Posted July 8, 2012 Author Report Share Posted July 8, 2012 Ahhhhhhhh, I get the point now exhaust temperature is really meaningless as this would be a combustion temperature thing THEORETICALY Combustion temperatures are pretty equal across the board on most engines but there are far too many variables so two identical models could be very different Ideally all of the combustible material in the 2 stroke oil would be consumed and no real oily goop would migrate into the exhaust, likely you would have substantially more unburned hydrocarbons from the fuel than you would the oil given that 98% of what goes into the cylinder is gasoline of suspect quality and the fact that a 2 stroke has a lot of abnormal combustion in a day But again, the variables, only the lab that the engine was designed in could test this properly I do not think there are too many variables here, as it seems to me the majority, or at least a fair amount of the oil is condensed in the lower end of the motor to provide contact protection of the surfaces. As the rpm and velocity of the mixture are slowed in low rpm operation, more oil accumulates in the bottom.(oil migration time slows) Now with an increase in throttle openings and rpm, this condensed oil is indeed put back in motion through slinging and increased air velocity getting tossed up top(the only way out) and eventually making its way to the combustion chamber. Some of the incoming mix may still be atomized with the fuel charge, and may be fairly well burnt with the ignition process, yert the part which is now syrup that makes it there is still exposed to the flamefront yet is not ignited. Not its purpose really, it is there to lubricate, not burn. The oil in the squish area of the combustion chamber has low flamefront exposure as well, long story made short it eventually gets spat out with the flow of things and will then accumulate in the exhaust.(oil migration time is lessened and it makes its way out, partially) Thankfully, modern oil does not burn well, doing its job, and continues to flow for the most part rather than produce a partially burnt carbon deposit in the motor. It is in that state that it will lay up in the exhaust unless one can keep it flowing with some velocity or actually manage to get enough heat in the exhaust to light some of it off and burn it out. Or both! It seems to me that both rpm and engine load are required to develop enough exhaust temps to either light off the grunge or keep it flowing, which is eventually spat out as smoke(as the case of the hillclimb) or spatter(oily mess that does eventually occur) and fings its way. Anything less is still laying up in the exhaust and once again, one does not want any more of this accumulation than need be, no more than he wants the smokey riders in front of him in the que. Quote Link to comment Share on other sites More sharing options...
copemech Posted July 8, 2012 Author Report Share Posted July 8, 2012 But seriously, isn't this something that we should all be concerned about? In the 60's and 70's people carried on working with asbestos, then those people became ill in the 90's. Now there are strict controls, that doesn't help those already exposed! I would nt be concerned with that exposure, yet at the same time I would not sniff the pipe! Quote Link to comment Share on other sites More sharing options...
copemech Posted July 8, 2012 Author Report Share Posted July 8, 2012 I've got a header pipe for my Jarvis that has never been fitted that contains a catalytic converter from memory, came in the full road kit supplied when I bought the bike new. The main jet fitted for running with the catalytic converter was only around 108 or so from memory so that tells you how much it must restrict exhaust flow Will dig it out & take a photo at some stage Have seem them things fitted for homogualtion emissions, so street legal in places I suppose. I would also expect them to run a smaller jet , yet for emissions reasons, and not neccessarily to restrict things. The cat may have some restriction to total flow at revs, yet may me a non-issue at lower revs. Not quite sure how the things would work in 2T application, yet I can tell you I prefer one on my diesel, as it cuts the stinch without loss of power. Quote Link to comment Share on other sites More sharing options...
0007 Posted July 9, 2012 Report Share Posted July 9, 2012 I do not think there are too many variables here, as it seems to me the majority, or at least a fair amount of the oil is condensed in the lower end of the motor to provide contact protection of the surfaces. As the rpm and velocity of the mixture are slowed in low rpm operation, more oil accumulates in the bottom.(oil migration time slows) Now with an increase in throttle openings and rpm, this condensed oil is indeed put back in motion through slinging and increased air velocity getting tossed up top(the only way out) and eventually making its way to the combustion chamber. Some of the incoming mix may still be atomized with the fuel charge, and may be fairly well burnt with the ignition process, yert the part which is now syrup that makes it there is still exposed to the flamefront yet is not ignited. Not its purpose really, it is there to lubricate, not burn. The oil in the squish area of the combustion chamber has low flamefront exposure as well, long story made short it eventually gets spat out with the flow of things and will then accumulate in the exhaust.(oil migration time is lessened and it makes its way out, partially) Thankfully, modern oil does not burn well, doing its job, and continues to flow for the most part rather than produce a partially burnt carbon deposit in the motor. It is in that state that it will lay up in the exhaust unless one can keep it flowing with some velocity or actually manage to get enough heat in the exhaust to light some of it off and burn it out. Or both! It seems to me that both rpm and engine load are required to develop enough exhaust temps to either light off the grunge or keep it flowing, which is eventually spat out as smoke(as the case of the hillclimb) or spatter(oily mess that does eventually occur) and fings its way. Anything less is still laying up in the exhaust and once again, one does not want any more of this accumulation than need be, no more than he wants the smokey riders in front of him in the que. The variables would be and not limited to High octane fuel, low octane fuel, octane boosters, engine condition, state of tune, modification, damage, plugged up muffler, dent in the head pipe, leak at a joint, worn jet needle, main jet size, winter fuel or summer fuel, (yes they are different in certain markets), age of the fuel (2 weeks in a Jerry can and the light ends are all vented to atmosphere unless you have a non vented steel container in a cold place) Air temperature, engine temperature, thermostat problems or just out of tolerance, air filter cleanliness, air screw setting, float height and or float needle wear and altitude of course etc etc There are no 2 bikes identical as every bike has a random number of the above going on at any given time And a comment on oil accumulation in the bottom end, yes and no, the oil would not separate from the fuel, it stays in suspension, considering the violent turbulent conditions within an engine, nothing really sits around long, it's possible for fuel and oil to accumulate down there under certain conditions but inevitably it would result in a rich condition in the combustion chamber at some point, but again, oil is only 2% of the mix I would say that any stuff coming out the back would be a combination of fuel and oil mix, it would take a chemist to separate the oil from the fuel And by the way, I agree that I don't really want to breath the stuff, much of the "fuel" we buy is a chemical mix, these are proprietary blends and no one is required to tell you anything more than the alcohol content Quote Link to comment Share on other sites More sharing options...
billyt Posted July 9, 2012 Report Share Posted July 9, 2012 Canuk maple syrup up against Texan BBQ sauce................... LOL Hey 0007 will you be at Ioco? "Mr Blowfeld, I like my oil shaken not stirred" Quote Link to comment Share on other sites More sharing options...
copemech Posted July 9, 2012 Author Report Share Posted July 9, 2012 The variables would be and not limited to High octane fuel, low octane fuel, octane boosters, engine condition, state of tune, modification, damage, plugged up muffler, dent in the head pipe, leak at a joint, worn jet needle, main jet size, winter fuel or summer fuel, (yes they are different in certain markets), age of the fuel (2 weeks in a Jerry can and the light ends are all vented to atmosphere unless you have a non vented steel container in a cold place) Air temperature, engine temperature, thermostat problems or just out of tolerance, air filter cleanliness, air screw setting, float height and or float needle wear and altitude of course etc etc There are no 2 bikes identical as every bike has a random number of the above going on at any given time And a comment on oil accumulation in the bottom end, yes and no, the oil would not separate from the fuel, it stays in suspension, considering the violent turbulent conditions within an engine, nothing really sits around long, it's possible for fuel and oil to accumulate down there under certain conditions but inevitably it would result in a rich condition in the combustion chamber at some point, but again, oil is only 2% of the mix I would say that any stuff coming out the back would be a combination of fuel and oil mix, it would take a chemist to separate the oil from the fuel And by the way, I agree that I don't really want to breath the stuff, much of the "fuel" we buy is a chemical mix, these are proprietary blends and no one is required to tell you anything more than the alcohol content Yes, there are these overall performance variables, yet within the premise of just how much oil is required it seems the variables are few. Engine load and rpm being the key. Now on the trials bike fitting into the spectrum it seems once again these things are at about the same level as whale shat! Here is another article that mentions bean oils and radiographic testing on migration times. No, the oil does not stay with the mix. It lingers! Pity, it does not get into the "whale shat" spectrum. http://klemmvintage.com/oils.htm Quote Link to comment Share on other sites More sharing options...
copemech Posted July 9, 2012 Author Report Share Posted July 9, 2012 I find the chart from Maxima a bit lacking of data, yet it goes along the lines of thought. http://www.maximausa.com/tech-tips/oil-migration.php Quote Link to comment Share on other sites More sharing options...
billyt Posted July 9, 2012 Report Share Posted July 9, 2012 Cope Does Spring Creek BBQ sauce separate from the meat if overcooked? Quote Link to comment Share on other sites More sharing options...
copemech Posted July 10, 2012 Author Report Share Posted July 10, 2012 Cope Does Spring Creek BBQ sauce separate from the meat if overcooked? Billy, BBQ is made with Beef, Not Pork! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.