y2k400ex
01-08-2003, 07:59 AM
This is some info from the tech page at www.Powroll.com about race fuel I thought it was helpful:
RACE FUEL
Q:
can i run cam 2 in my stock 2001 honda xr250r will it harm it i will use it one a week to race. U know the extra littel edge it will give me on excelaratoin
james
A:
Yes, you can run race fuel (for ease of understanding here, we'll consider race fuel as something with an octane rating of over 105, with lead) in any engine without hurting it. The question really is, do you want to? Or will it give you more "excelaratoin" (whatever, that is!).
Race fuel burns at a lower temperature than lower octane fuels. This allows high compression engines to run well without banging holes in the piston. It also allows lower compression engines to survive in very hot/tough conditions. If you are racing in sand, mud or hot/humid conditions, adding leaded race fuel to your tank will make your engine run cooler. And, yes, it may give you better acceleration and nice throttle response.
However, if you run straight race fuel, you will probably be 'wasting' octane.
The best option for your application is to run 1/2 race fuel and 1/2 pump fuel. This will give you the cooling and quick burning properties of the race gas, without increasing the octane to a point the engine isn't utilizing it.
Basic points of reference:
Up to 10.5:1 Compression - 1/2 race gas, 1/2 premium pump.
10.75:1 to 11.5:1 Compression - 1/2 & 1/2 for regular riding, straight race fuel at low elevations, race applications, or power-robbing soils (sand, mud). For engines over 200cc's, anything 11:1 and over, don't EVER run straight pump fuel!!
11.75:1 to 13:1 - Straight race gas, all the time!!!
Note: Aviation fuel is not race gas. Aviation fuel is designed to work well at high elevations and low rpm. Completely opposite of your dirt bike or ATV! Aviation fuel can damage your engine.
RACE FUEL
Q:
can i run cam 2 in my stock 2001 honda xr250r will it harm it i will use it one a week to race. U know the extra littel edge it will give me on excelaratoin
james
A:
Yes, you can run race fuel (for ease of understanding here, we'll consider race fuel as something with an octane rating of over 105, with lead) in any engine without hurting it. The question really is, do you want to? Or will it give you more "excelaratoin" (whatever, that is!).
Race fuel burns at a lower temperature than lower octane fuels. This allows high compression engines to run well without banging holes in the piston. It also allows lower compression engines to survive in very hot/tough conditions. If you are racing in sand, mud or hot/humid conditions, adding leaded race fuel to your tank will make your engine run cooler. And, yes, it may give you better acceleration and nice throttle response.
However, if you run straight race fuel, you will probably be 'wasting' octane.
The best option for your application is to run 1/2 race fuel and 1/2 pump fuel. This will give you the cooling and quick burning properties of the race gas, without increasing the octane to a point the engine isn't utilizing it.
Basic points of reference:
Up to 10.5:1 Compression - 1/2 race gas, 1/2 premium pump.
10.75:1 to 11.5:1 Compression - 1/2 & 1/2 for regular riding, straight race fuel at low elevations, race applications, or power-robbing soils (sand, mud). For engines over 200cc's, anything 11:1 and over, don't EVER run straight pump fuel!!
11.75:1 to 13:1 - Straight race gas, all the time!!!
Note: Aviation fuel is not race gas. Aviation fuel is designed to work well at high elevations and low rpm. Completely opposite of your dirt bike or ATV! Aviation fuel can damage your engine.