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Explain flash point (premix)

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Sorry for a question thats prob has been answered. I keep hearing that certin flash points are better for different tes of riding, Explain?

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first off unless you have the flash point limits none of it is going to do you any good (even if you do its a who cares)..there are 2 things here 1 of which is UEL (upper explosive limit) and LEL (lower explosive limit)...to generate burn you must be within those limits..there are no exceptions to the rule...to much oxygen and your outside you UEL...to little and your below your LEL..hence no burn....this is as simplistic as i can put it...really if your plug is correct color your set up is correct....course assumes your machine is in good working order and i dont care what kind of gas you run.....it all has to fall within those limits...ok ive fallen into the trap with this explanation..no biggie so why not raise more hell and let all the experts fight it out..contrary to poular belief (argue away)..it is not very well understood what exactly occurs inside the jug on ignition..oh we have the basics and i know somebody will say they have a photograph of the flame inside the jug..again i dont give a rats ass...whats not understood is why things occur as they do on a molecular level..kinda like a thermo couple...nobody really can explain why 2 dissimilar metals produce electrons to behave in the way they do when heat is applied or not (phenomenen)..we just know it works...another expample is the elctro magnetic field around your stator, generator or alternator...we know its there as we can meausre it but it has never been seen..NEVER...what we do know from measuring is that magnetic field hold current and when your points open (ok im old but cdi functions the same) the fields collapsed and sends the current to that big grey thing called and IC (aka transformer)...sooo to end this if your bike runs like a banshee now..just document the results (mix ratio/brand of pre-mix/etc) so you dont forget and go with it

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This might be completly wrong, but i think, in a simple way, premixes with a lower flash point would be good for trail riding or larger bore bikes, becuase they dont rev high and/or run as hot, so the low flash point premix would all burn and keep the engine clean, were as if it was a high flashpoint premix, it wouldnt all burn and leave your engine gummed up.

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Mixed with 98% gasoline any difference in the oils FP is practically nothing. If you trying to relate it to smoke. carbon, drool, the msds FP spec means nothing, nor was it ever meant to.

A % of the base oil content will usually contain a heavy molecular weight stock, maybe bright stock 100, 150 in a mineral blend, or a heavy PIB in a synthetic blend, or castor. That % in amount, and the actual ingredient used will more so determine how much is oxidized during combustion and whether it gives off more or less smoke or unburnt byproduct like ash or drool. PIB's burn cleaner, but mineral bright stock can protect better, castor protects really well . Since the move to (cleaner) powervalve formulations have favored PIB's as the heavy (or big) of choice because it burns off cleaner. BUT, to get the same protection of the old mineral oil bright stock more has to be used, which some blenders feel is a wash. Same sort of story with castor. Which is why there are differing oils from the same blender suited for different jobs, or compromises. There is no such thing as a super clean oil that is also a super protecting oil.

Outboard motor oils don't usually use any of heavier weight oils (think bigger size ball bearings) in their base oil because of the low specific output, and low rpms. Test have shown it usually causes more problems than it helps. It's absence in a high output motor like a mx bike (like using outboard oil in a race bike) will usually show up as crank bearing wear, the top end is usually OK. UNLESS, the ratio was significantly increased which can compensate for the lack of the heavier stock. This without going into the other differences between the oils.

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