Banchetta Posted December 22, 2003 Report Share Posted December 22, 2003 Agreed, but most people that port will also raise the compression back up w/ a head mod or smaller domes....What is the point of porting if you loose compression. The power you gain from porting will be lost in compression, so you should keep the compression up..... Quote Link to comment Share on other sites More sharing options...
spoin39 Posted December 23, 2003 Report Share Posted December 23, 2003 If you're not running a higher compression than stock high octane fuel is a waste of your money. I had a friend that thought race gas = more power so we filled up two stock banshees at the local moto shop and dragged each other and switched machines so it wouldn't be a rider issue and they were almost dead even everytime! One just smelled better....aahhh, love that smell! Quote Link to comment Share on other sites More sharing options...
Blue Duece Posted December 23, 2003 Report Share Posted December 23, 2003 in defense of the guy running race fuel on a stock motor, he's rebuilding less.... Quote Link to comment Share on other sites More sharing options...
balelorf Posted December 23, 2003 Report Share Posted December 23, 2003 I wish I had the article handy, it was in a circle track magazine a couple of years ago. They ran Chevron 92 pump unleaded in a race motor and it ran really hot, boiling of the radiator, however they made about 550hp. They dumped in 110 octane race gas and ran about 20 degrees cooler but made about 530hp. Greatest illustration I ever saw on why you run race gas was that dyno chart and radiator temps, it's not for horsepower no matter what anyone thinks they feel. Quote Link to comment Share on other sites More sharing options...
boonman Posted December 23, 2003 Report Share Posted December 23, 2003 I would be willing to bet on that motor that was near boiling over on pump fuel was detonating on pump fuel. That is the reason for it heating up. And cooling it down immediately when they switched to race fuel. because of the extra cooling properties of Race Gas, the motor runs cooler therefore the motor will run "more crisp". Nonsense. There are no "extra cooling properties"in race and higher octane fuels. They simply combat detonation in high compression applications. The only cooling properties that would be existant on a stock motor would be all the unburned fuel in the cylinder that may cool it down some. What about when u get the bike ported and lose compression , like a major change then before the port? ..Do u then go back to a lower octane fuel such as 94 from sunoco? or do u continue running race fuel? I say go back to 94 does anyone agree? I do NOT agree. Based on the reasoning that no matter how much porting is done which reduces the amount of air that can actualy be compressed, you still didn't change the squish on the head. most cases this is done, to get a smaller volume of which is trapped at TDC. Let's say you were running hig hoctane fuel on a stock ported bike. Your squish was minimal, let's say .020". A really low number. So, you get the thing drag ported. But, you don't change the head. You will now show a considerably lower number on a compression guage, however, this should not be the determining factor when deciding on what fuel to use. Because, if you were to run some 91 octane in this hypothetical motor, you would surely blow a hole in the piston. Run what doesn't let your bike ping. If you like to run race fuel, and don't need it, do it. You will have alot of unburned fuel exiting out the pipes in a vapor trail. Whatever floats your boat....... Quote Link to comment Share on other sites More sharing options...
Forcefed Posted December 24, 2003 Report Share Posted December 24, 2003 Anyone want to get into this again??!! Never...ever, ever, ever, ever base your octane rating on your cranking compression. I have no choice but to run 114 octane or higher.....and I only have 165 psi. Quote Link to comment Share on other sites More sharing options...
Nightrider Posted December 24, 2003 Report Share Posted December 24, 2003 I ran 110 in my Shee for a while,It never ran really good at lower speeds.I was running 21cc and +4 timing.Thought I needed the octane. The gas was getting expensive,so I decided to try premium pump (Sunoco 94) and an octane booster.I figured the it to be about 95 with the booster. The engine was noticeably more responsive on the low-end and there was a definite crispness in the throttle.That extra octane in the 110 seemed to hurt the engines responsiveness. Quote Link to comment Share on other sites More sharing options...
Blue Duece Posted December 24, 2003 Report Share Posted December 24, 2003 Anyone want to get into this again??!! Never...ever, ever, ever, ever base your octane rating on your cranking compression. I have no choice but to run 114 octane or higher.....and I only have 165 psi. same here..im at 180psi at 2500 feet on 19cc domes i can only get 108 or 118 so i run the 118.... Quote Link to comment Share on other sites More sharing options...
Banchetta Posted December 24, 2003 Report Share Posted December 24, 2003 Agreed, I put some in my shee and my streetbike and both situations felt a lost in responsiveness.... Boony, I was told by Paul Turner that high octane will make your shee run cooler since it doesn't burn as hot......Sounds logical, though I've never experimented to test this theory.....Anyone have some hard facts on that???? Quote Link to comment Share on other sites More sharing options...
boonman Posted December 24, 2003 Report Share Posted December 24, 2003 The only thing I find hard to believe on that theory Chetta is that just using race fuel and knowing nothing else about the motor, can be helpful/beneficial, or just a flat out waste of money. If race fuel made the bike run cooler when compared to pump fuel, then there was surely a problem with detonation. And that was making the bike run hot. I still do not believe that just by running race fuel it will make the bike run cooler. Only when the fuel doesn't get burned. That would be the only explanation I can think of that would make it run cooler.... Quote Link to comment Share on other sites More sharing options...
Big Mike NY Posted December 24, 2003 Report Share Posted December 24, 2003 I still do not believe that just by running race fuel it will make the bike run cooler. It won't. The race gas will make a motor that requires the higher octane run cooler. A motor that doesn't need the high octane will not run any cooler than on pump gas. Quote Link to comment Share on other sites More sharing options...
mcaf29 Posted December 24, 2003 Report Share Posted December 24, 2003 I've been told race gas will run cooler (Line Mike NY said in a bike that needs it) because of two reasons. The first reason is, it is more pure therefore less crap burning to cause a non-uniform burn in the cylinder. The second reason is its chemical make up absorbs more heat (remember gas cools the piston not the coolant). Its the same idea as rubbing alcohol on your skin, it gives you a cool feeling cause it pulls the heat from your body as it evaporates. Quote Link to comment Share on other sites More sharing options...
98bonerSTOCKshee Posted December 24, 2003 Report Share Posted December 24, 2003 dude........ I do NOT see how race fuel will slow you down. Here's my testimony... I ran race fuel once this past thanksgiving at Glamis... this was only because I was running outta gas and had money in my pocket to buy some gas from some guys camped five miles away from my camp. Now, I hit them up and all they had was race gas that they were running in their banshees. I don't know what it was that was in there, but the guy said, this gas is the shit........... Now, I pay him, fill up and take off.... we're flying through the dunes back to camp and I thought I could feel the power gain when I would open the throttle up on the long straightaways... when we got back to camp my buddy tells me.... "dude, you need to keep running whatever that guys gave you" I said "why?" .. then he says, " before you got that stuff, I could easily catch up to you on the straightaways, but now I'm really struggling to catch you".... even HE noticed the difference and he wasn't even riding my bike......... RACE FUEL DOES NOT SLOW YOU DOWN........ oh yeah... I ride a 2002 banshee ALL STOCK with FMF Fatty's and K/N filter.... my honest testimony.. I like the smell !!! ha! ha! Quote Link to comment Share on other sites More sharing options...
98bonerSTOCKshee Posted December 24, 2003 Report Share Posted December 24, 2003 I still do not believe that just by running race fuel it will make the bike run cooler. It won't. The race gas will make a motor that requires the higher octane run cooler. A motor that doesn't need the high octane will not run any cooler than on pump gas. This thanksgiving @ 'lil Sahara I used the purple gas on pump. It's rated at 110 @ 5 bucks a gallon. I did feel preformance increase, but the 'shee wasn't running any coolr..(I have been having coolant issues) My motor has stock squish, I probably was throwing a way a $2.50 a gallon as to compared to the better squiched motors that would take full advantage. Never the less I love the smell.. To add to the brain buster... This was my 3yr old sons 1ST away from the backyard ride. He has a '85 yamaha trimoto 60 (if ya'll remember them) His ride and mine were the only 2 strokers in the group. (I can't help that ) But rather taking the time to mix gas for his and mine he got the purple stuff... You would be amazed, being the father figure I am always take his ride for a test run after my clumpsy hands have tuned it in anyway..I felt more increase in performance on the TriZinger than the 'shee.... Quote Link to comment Share on other sites More sharing options...
Big Mike NY Posted December 25, 2003 Report Share Posted December 25, 2003 You guys should read this: http://www.atvdra.com/forums/index.php?sho...&st=0entry200 I'm telling you now, I don't care what you say, there is no way (scientifically or mechanically) that a stock motor will benefit from high octane race fuel. The guys that claim they felt an increase from using race gas have been influenced by a "Placebo Effect". You are running race gas therefore your mind is telling you "Hey, the bike seems faster". I'll put money on it that its not faster. If anyone cares to dyno a stock banshee with pump gas and race gas, I'll put up $100 that says there is zero power increase and possibly even a power loss. If I'm right, you pay me $100, if I'm wrong you get the $100 + dyno fees. All info must be posted (ie; dyno graphs, type of gas used, engine modifications, etc). No other changes to the bike are to be made except the fuel. Any takers???? Quote Link to comment Share on other sites More sharing options...
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