450r gas ?
Nov 11, 2004 | 02:35 PM
#1
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Extreme Pro Rider
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450r gas ?
I know they recommend 91 octane min. but is it absolutely neccesary? I only ask because I don't carry gas cans 'cause my trailer has a 36 gallon gas tank and I aint filling that up with 91 at $2.50/gallon just to let my generator eat it all up! Anyone run lower octane in theirs? Should I just invest in a couple of cans for the 91? I just picked the quad up last week and I'm taken it for it's maiden voyage this weekend to break it in so I was curious what you guys run in yours. Thanks for the advice............
Nov 11, 2004 | 03:11 PM
#2
Pro Rider
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450r gas ?
invest in gas can. dont get cheap on your investment. chances are if you run 89 or 87 you wont detonate and beat the bearings out of it, but why even chance it? gas cans are cheap reassurance.
edit: forgot to add a word. [img]i/expressions/face-icon-small-tongue.gif[/img]
edit: forgot to add a word. [img]i/expressions/face-icon-small-tongue.gif[/img]
Nov 11, 2004 | 03:13 PM
#3
Trailblazer
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450r gas ?
If they call for 91 I would put 91 in it. See the probelm you might have with running lower octane is Knock. Knock is not good, it can distroy your motor. Basically what happends is the gas explodes before the spark plug ignites it and damages the piston. I deal with this problem with my car, with it being boosted I have to deal with Knock or KR (Knock Retard). What is the compression ratio on the 450R motor?
Nov 12, 2004 | 12:38 AM
#6
Red Rider
Honda, accept nothing less!
Honda, accept nothing less!
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450r gas ?
450R owners manual says 86 or higher! Must be a mistake???
400EX manual says 92 or higher (you EX owners getting this?)! Pump gas around here is 91 which is to low, so I mix 1:5 pump gas and 108 octane race gas (final octane =94.4) for the 400EX. I just use that mix in all my performance bikes, the 450R, Z400, and 400EX.
400EX manual says 92 or higher (you EX owners getting this?)! Pump gas around here is 91 which is to low, so I mix 1:5 pump gas and 108 octane race gas (final octane =94.4) for the 400EX. I just use that mix in all my performance bikes, the 450R, Z400, and 400EX.
Nov 12, 2004 | 12:34 PM
#7
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450r gas ?
The 450R has 10.5:1 comp ratio stock. If you install the HRC cam, the static compression will drop, as it has a bit ov overlap. I have always run 91, but at 10.5:1 that is more octane than you need.
The reason the 400ex wants 91 or higher is because its air cooled, and much more prone to detonation, preignition, and heat.
Running more octane than needed will not improve power, it can in fact hurt power, because higher octane fuel is more stable at higher temps and pressures, so lower compression engines can struggle to burn all the fuel.
I stole this from pulsecahrger.net, I did not think I could make it sound as good as John....
The reason the 400ex wants 91 or higher is because its air cooled, and much more prone to detonation, preignition, and heat.
Running more octane than needed will not improve power, it can in fact hurt power, because higher octane fuel is more stable at higher temps and pressures, so lower compression engines can struggle to burn all the fuel.
I stole this from pulsecahrger.net, I did not think I could make it sound as good as John....
Octane is purely a rating of fuel stability, not of power potential. The higher the octane, the more stable it burns when subjected to higher pressures and temperatures. Contrary to popular belief, the fuel and air mix doesn't explode when the spark ignites it. It burns very rapidly, but it is still a progressive burning.
Pre-ignition is when heat and pressure cause the initiation of combustion prior to the ignition's spark. Detonation is an explosion caused when a majority of the mix spontaneously and simultaneously ignites. This creates an enormous pressure "spike" and can turn your favorite motor into a great boat anchor in very short order.
Detonation also occurs when the heat and pressure limits of a fuel's stability has been exceeded. The higher the octane rating, the more resistant that fuel is to pre-ignition and detonation. It will burn in a more controlled (slower) and stable fashion, thus you can run more compression. This is also why, unless your engine has been modified to take advantage of these properties, you can and will actually run slower using race fuel
The main advantage of high octane fuel is being able to increase your compression levels to the 13:1 to 14:1 range without fear of detonation. Four strokes LOVE compression and that love can be felt every time you crack the throttle. Increasing compression has several advantages:
Pre-ignition is when heat and pressure cause the initiation of combustion prior to the ignition's spark. Detonation is an explosion caused when a majority of the mix spontaneously and simultaneously ignites. This creates an enormous pressure "spike" and can turn your favorite motor into a great boat anchor in very short order.
Detonation also occurs when the heat and pressure limits of a fuel's stability has been exceeded. The higher the octane rating, the more resistant that fuel is to pre-ignition and detonation. It will burn in a more controlled (slower) and stable fashion, thus you can run more compression. This is also why, unless your engine has been modified to take advantage of these properties, you can and will actually run slower using race fuel
The main advantage of high octane fuel is being able to increase your compression levels to the 13:1 to 14:1 range without fear of detonation. Four strokes LOVE compression and that love can be felt every time you crack the throttle. Increasing compression has several advantages:
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Nov 12, 2004 | 12:51 PM
#8
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450r gas ?
I also recommend NOT mixing fuels.
and I quote
"Are you a petrochemist? If you're not, don't do it.
Do you have the proper test equipment to know what you are getting when you are done? If you don't, don't do it.
Do you actually know the outcome of "mixxing" fuels? If you don't, don't do it.
Some engine builders say it's the "only way to make the bike run right" or some e like that. It's the same engine builder that is always waiting for parts, or his bike really rips but, everytime you talk to him it's apart for some reason. It's the same guy that dumped 1 gallon of 93 unleaded into one gallon of AV gas and says he has 96 octane fuel.
Let me just tell you to NOT mix fuel types. I've seen some unbelievable concoctions that people say it's makes their bike run better. Until I prove them wrong. Run race fuel, or don't. Run leaded fuel, or don't. Run pump gas, or don't. Use whatever you want, I don't care. But when you're sitting alongside the trail with a holed piston, bent rod, broken valves, snapped cam chain, or ventilated crankcases threw a hole that wasn't there when you bought the thing, you can't say I didn't warn you."
More
"Mixxing" gasolines is very dangerous to engines. Especially when you "mix" unleaded and leaded fuels. Depending on some of the agents used to blend the fuels, this can make some very caustic compounds that are incredibly unstable and prone to detonation. And it gets worse when oxy leaded fuels are mixed with unleaded alcohol fuels. Anything that is aluminum is at severe risk. I've seen exhaust ports of engines that looked like they had been in acid baths and were only several hours old. "
Now, I will not name my source, as I did not have his permission to post that, he would not mind, it was posted elsewhere, but he is a VERY informed and well connected engine builder. I know many of you have done this for years, and I have done it too, but if you think about it.....
Many pump stations sell 100 octane for about $2.90-$3.25 here. WIth 91/93 being $2.25, its a no brainer.
and I quote
"Are you a petrochemist? If you're not, don't do it.
Do you have the proper test equipment to know what you are getting when you are done? If you don't, don't do it.
Do you actually know the outcome of "mixxing" fuels? If you don't, don't do it.
Some engine builders say it's the "only way to make the bike run right" or some e like that. It's the same engine builder that is always waiting for parts, or his bike really rips but, everytime you talk to him it's apart for some reason. It's the same guy that dumped 1 gallon of 93 unleaded into one gallon of AV gas and says he has 96 octane fuel.
Let me just tell you to NOT mix fuel types. I've seen some unbelievable concoctions that people say it's makes their bike run better. Until I prove them wrong. Run race fuel, or don't. Run leaded fuel, or don't. Run pump gas, or don't. Use whatever you want, I don't care. But when you're sitting alongside the trail with a holed piston, bent rod, broken valves, snapped cam chain, or ventilated crankcases threw a hole that wasn't there when you bought the thing, you can't say I didn't warn you."
More
"Mixxing" gasolines is very dangerous to engines. Especially when you "mix" unleaded and leaded fuels. Depending on some of the agents used to blend the fuels, this can make some very caustic compounds that are incredibly unstable and prone to detonation. And it gets worse when oxy leaded fuels are mixed with unleaded alcohol fuels. Anything that is aluminum is at severe risk. I've seen exhaust ports of engines that looked like they had been in acid baths and were only several hours old. "
Now, I will not name my source, as I did not have his permission to post that, he would not mind, it was posted elsewhere, but he is a VERY informed and well connected engine builder. I know many of you have done this for years, and I have done it too, but if you think about it.....
Many pump stations sell 100 octane for about $2.90-$3.25 here. WIth 91/93 being $2.25, its a no brainer.
