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Discussion Starter · #1 ·
Hey everyone, just recently got ahold of a 525xc, its got a JE 13:1 piston, 8/06 cam, and full HMF exhaust. I know that the higher comp. pistons require a higher octane fuel to run right, but I'd like to know if I can get away with just the pump premium or if i will need to go with a 50/50 mix.....race gas isnt too appealing since my wallet is lookin a little skinny as of late (College student :p ) So thanks for any ideas and suggestions!
 

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Hey man, what I would suggest is a 50/50 mixture of race fuel and pump gas. You could possibly run 93 and get away with it, but I'm not 100% sure. Wait for some suggestions from guys who have done this.

Thank you, Jay
 

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In most cases, anything over 12:1 requires race gas or at least a mix of race and pump gas (50/50). You might have to experiment with different ratios. You definitely want to avoid detonation. That is when the compression and heat cause the gas to combust too early. Detonation negatively effects performance and can damage the engine.
 

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Discussion Starter · #4 ·
Okay thanks guys, just a pain for race gas cuz the nearest station is like 45min away. Anyone else have any experience with this??
 

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nitro......... we'll all watch while you try that one............ :wacko:
 

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try this stuff i swear by it, ive used it in bigbore stroker motors with comp well over 14to1
for of hours no problems at all. i hated buying race gas @ 8 to 11 dollars a gallon.
just get fresh super and figure how high you want your octane and pour it in. i used 1 quart per 5
gallons.


hundhttp://www.kemcooil.com/products.php?cId=4ers
 

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Discussion Starter · #8 ·
Thanks, Ill keep that in mind, definetly looks like a good option!
 

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Discussion Starter · #9 ·

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i would definitely try and run race gas. All the way, no mix....the power gains are pretty noticeable even in a stock engine. And with a 13:1....ide try 108 or higher to get the full potential out of it. You got a monster in that engine.....give it some food ;)
 

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c12 wont go in any bike I ever run. it robs power and Ive proven it on the dyno numerous times. Sunoco or vp 110. More than enough octane for up to 14.5 compression. I prefer sunoco, its cheap and works awesome. ive never lost a motor Ive assembled running straight sunoco.
 

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its not anything over 12:1 its anything over 13:1 you should think about it. My kawi comes with 12.1:1 factory and i put a 12.8:1 and run prieum and it put down 52 rwhp.
 

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have you ever tried running something like Klots 108 or 113 in it yet? If not, try it and get back to us. Im telling you, you will be impressed. Its snappier, and pulls harder....i promise
 

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I would love to see dyno sheet proving that race gas in a motor that does not require it makes more power. Logically makes no sense.

Octane retards the burn of fuel so it will not ignite off the compression. higher octanes mean slower burn rate which when you do not have the compression is a waste of money and possible power loss.

Had my 13.5 piston in hand I ran 10 gallons of mixed premium and race gas through and it looked fine.
 

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QUOTE
its not anything over 12:1 its anything over 13:1 you should think about it. My kawi comes with 12.1:1 factory and i put a 12.8:1 and run prieum and it put down 52 rwhp.
There are other factors to consider; air temp, air flow, cyl shape and design, hot spots, your trying to prevent detonation and a 12.8 w/ pump gas is pushing it. It may not cause a prob w/yours but an identical bike could have a problem.

QUOTE
I would love to see dyno sheet proving that race gas in a motor that does not require it makes more power. Logically makes no sense.

Octane retards the burn of fuel so it will not ignite off the compression. higher octanes mean slower burn rate which when you do not have the compression is a waste of money and possible power loss.
I agree the most power will be made with the lowest octane that will not detonate/preignite. This does not factor in oxygenates though.
 

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I would love to see dyno sheet proving that race gas in a motor that does not require it makes more power. Logically makes no sense.

Octane retards the burn of fuel so it will not ignite off the compression. higher octanes mean slower burn rate which when you do not have the compression is a waste of money and possible power loss.

Had my 13.5 piston in hand I ran 10 gallons of mixed premium and race gas through and it looked fine.
Its all in peoples minds. LOL Putting over 100 octane into a bike under 13.1 compression only does one thing. Puts your money in someone elses pocket. No gains to be had that Ive seen.
 
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