I have a 07 800R summit X-RS. I hear that running race gas let's your motor run cooler. Is it worth the extra cost?
Thanks
Thanks
Let's talk about race gas!
- Thread starter PolarsPaco
- Start date
NO. If you dont have the compression to use the octane you are wasting money and hp. The lowest possible octane rating you can safely run your engine on will give you the best hp.
VP U-2 fuel will give you a slight gain in hp because the fuel carries extra oxygen. But you will have to jet up, and it is NOT worth the price per gallon.
VP U-2 fuel will give you a slight gain in hp because the fuel carries extra oxygen. But you will have to jet up, and it is NOT worth the price per gallon.
T
trinitypowder
Well-known member
Mod the motor with porting and a hi compression head just so you have to run race gas. The smell is worth the price of admission!
Total waste of money. Your sled with run worse.
Mod the motor with porting and a hi compression head just so you have to run race gas. The smell is worth the price of admission!
It's Very Nice!!
T
trinitypowder
Well-known member
After reading your signature, I realize why you get the smell thingy.......a CR500 rider! I have a '93 that I just finished restoring. I love the beast! We had a slight disagreement last Saturday however, and ended up parting ways...............the bike won
I think I saw that get-off. You must be the dude roosting all the kids with that old, evil CR. Your googles must have landed in a different zip code!
P
portgrinder
Well-known member
Higher octane fuel does not give or take away power.
Higher octane fuel allows your engine to survive at a higher state of tune.
Higher octane fuel allows your engine to survive at a higher state of tune.
$300.00 for a 55 gal drum of 110.....The other day the airplane i was on had a strong tail wind therefore approached the runway early & 200# heavy on jet fuel. The tower told the pilot he was to heavy for the short runway so he had to stay in the air for approx 8 more minutes to burn the 200# of fuel at a cost of approx $800.00
OT
OT
Yes a higher octane than the compression requires WILL take power away.
You can do a search on the net and find hundreds of sites backing this up.
I do own a shop and have logged tons of dyno hrs.
MOTO HEADZ RACING
I build engines and port heads for my sponsored riders and a few race teams. Sorry I dont offer much for the general public.
Octane does not equate to power.
Octane is the fuels ability to resist detonation.
The higher the octane value, the more you can compress the mixture and this is where the extra power comes from (or add more timing etc). Just running a different fuel will not provide any seat of the pants power increase (that you can notice when riding IMO).
Running your motor cooler does what for you? The hotter the better (to a point). If you are running a stock liquid cooled motor, run what the manufacturer states to run it, this is what it was designed for.
If you have mods, then you need to discuss them with your builder or if you did them yourself, have a clear understanding of what you did.
The combustion process of race fuel and regular pump gas are different and without going into a huge explanation of heat transfer, vapourization and fuell components here, I will simply say yes, it does burn "cooler" (albeit more completely) but unless you are have swapped in a race bred air cooled motor from the late 70's to your XRS, you probably should save your money.
Another thing to consider is what your motor is set up for. Long story short - (since it was at the end of its purpose-built existence) I put a blend of nitrometh and race gas in one of our race cars to see what it would do - it made one warm up session and two practice sessions (about 20 mins running time) before grenading the rod bearings. The added force of the fuel in the combustion chamber essentially pounded the bearings right out of it. Depending on the fuel type you are using, it may eat your seals and do more damage than harm.
Octane is the fuels ability to resist detonation.
The higher the octane value, the more you can compress the mixture and this is where the extra power comes from (or add more timing etc). Just running a different fuel will not provide any seat of the pants power increase (that you can notice when riding IMO).
Running your motor cooler does what for you? The hotter the better (to a point). If you are running a stock liquid cooled motor, run what the manufacturer states to run it, this is what it was designed for.
If you have mods, then you need to discuss them with your builder or if you did them yourself, have a clear understanding of what you did.
The combustion process of race fuel and regular pump gas are different and without going into a huge explanation of heat transfer, vapourization and fuell components here, I will simply say yes, it does burn "cooler" (albeit more completely) but unless you are have swapped in a race bred air cooled motor from the late 70's to your XRS, you probably should save your money.
Another thing to consider is what your motor is set up for. Long story short - (since it was at the end of its purpose-built existence) I put a blend of nitrometh and race gas in one of our race cars to see what it would do - it made one warm up session and two practice sessions (about 20 mins running time) before grenading the rod bearings. The added force of the fuel in the combustion chamber essentially pounded the bearings right out of it. Depending on the fuel type you are using, it may eat your seals and do more damage than harm.
If you guys are looking for ways to run cooler temps in your mods i would suggest adding "water wetter". The NHRA boys use the stuff to reduce internal engine heat by as much as 30%
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I think he meant internal engine temps not coolant/water temps. Water wetter works good but not with coolant, only drops the temps a little bit, better to use with straight water, it drops them about 20-30 degrees or so with straight water, only like 5-10 with coolant. Can't use straight water in the sled (I know you know that ).
).Dude thats a WICKED avatar! whats the stretch on that swing arm?
i have a new 09 xp with a rtk head, crank shop pipe and reeds. i was going to burn av gas in it. 100 octane with low lead. any opinions?
You might want to look up AV gas on the net. I dont have the time or the typing skills for this one.
I have used AV gas in just about everything and it will work. Its the burn rate of AV gas is why its not the best fuel for 2 strokes. For example a 2 stroke engine with a 80 mm stroke and 180 deg of port timing actually only has a 40 mm power stroke because of the fixed port in the cylinder. A 2 stroke needs a fast burn rate for optimum hp output. AV gas has a very slow burn rate designed for very long stroke low rpm torque engines.
I have used AV gas in just about everything and it will work. Its the burn rate of AV gas is why its not the best fuel for 2 strokes. For example a 2 stroke engine with a 80 mm stroke and 180 deg of port timing actually only has a 40 mm power stroke because of the fixed port in the cylinder. A 2 stroke needs a fast burn rate for optimum hp output. AV gas has a very slow burn rate designed for very long stroke low rpm torque engines.
If your engine operates at 10000 ft and above and turns 2800rpm max av gas is for you.