What do you think on Race fuel?
 

Buddy, has just got a shipment of race fuel(I live in Indy, its common) for his race car. Well, I put sta-bil at the end of fall in my tank. My question is you think a gallon of 103 octane will help refresh the gas and be all right to use with the carbs? It does have a lot lower flash point. Maybe use it on a regular basis too. What do you think?

if your bike isnt tune to run on race fuel it will be a waste of $$$$

you could but i would add much

no tune for race fuel = waste

probably will make it run slower lmao

ive put av-gas in my F2 awhile back and felt a nice amount of potential from the extra octaine. ( 100 octaine)

keep using av gas and you will notice more than that ;)

I was only thinking a gallon to refresh it. Maybe take a few gallons for a weekend at Deals Gap. I run 93 in it keep it running smooth. I do see how not tuning it would lead to a waste. But was wondering if it ruined the carbs?
I can get race fuel cheap, so not out of too much money.

Race gas will do nothing for you. With stock compression, cam grind, cam and ignition timing, running anything above 87 octane will do nothing for you. Higher octane fuel is less volatile and therefore pre-detonates at higher pressure, allowing you to run higher compression and run properly. It won't do anything for your F2, it'll just cost you more every fill up. Save those dollars and use them for something worthwhile like good synthetic oil.

Speaking of synthetic, can you use regular Mobil-1 synthetic 10w-40 oil in our bikes? I need to change the oil for spring. What is the recomendation?

+1


and Don't use car oil in you bike unless you are really sure about it. The engine oil in our bikes is shared with the transmission/clutch which means most car oils won't work (especially if they say 'cleaners added' or "high mileage engines"). Use a Motorcycle specific oil. (I would recommend Amsoil full synthetic but it is pricey).

Agreed.

However there are some car oils that work well. I use the Shell Rotella T 5W-40 full synthetic in all my watercooled bikes. It has excellent viscosity and heat range, and is cheap. I've seen no clutch slipping and I do know tons of people who run it. Here's a chart on some good oils to try. This guy has some good research on it and his oil filter chart is spot on too.

http://www.calsci.com/motorcycleinfo/Consumables.html

whats wrong with using av gas? It smell nice and leave a funny white residue on your muffler... is lead ok?:icon_eek:

So you are saying are bikes are set up for 87 octane? Makes the Japenese sound like american car builders. Something isn't it right with that.

I understand timing and compression with lower octane(more Hp with more detenation). But the Japenese to sell a bike that takes 87 octane is too weird to believe with carbs.

Tons of japanese bikes run 87 octane. Honda specifies 86 AKI octane (the rating at the pump) for the F2. Our engines are not too crazily designed. They are only 11.6-1 compression (which isn't a huge amount for a watercooled 4 stroke). They're pretty well cooled and have an aluminum head, which will allow you to run lower octane fuel. I don't know too much about the head and piston design, or the cam or ignition timing, but they're not aggressive, especially by modern sportbike standards. Honda wouldn't specify 86 octane if it'd damage the engine, they'd make us spend an extra 10-20 cents a gallon.

11.6-1 compression is very aggressive! Try doing that to your civic and you couldn't get around to changing the oil on 87 octane. It would either damage the valves or burn a hole through the piston.

Nascar has 14-1 compression and most cars have 9.5-10 to 1 compression. I am going to have to try this crazy idea on 87 octane.

I did only get 72hp on 93 octane on the dyno. I will have to see. You know that lower octane has a higher flash point an creates more heat right?

uhh... I am pretty sure my owners manual specified to run 90 octane at the minimum... I will have to check it when I get home tho...

Trust me, the manual says 86 octane AKI required, and some bikes have the 91 RON octane fuel sticker or rating in the manual. These are all just different ways of calculating octane and AKI octane is what's put on the pump in the US, and is 5 points lower than RON, which is used in Europe.

Another reason why you don't need premium in the bike is the small size of the piston. The flame front does not have to travel far and therefore you won't have problems with knocking with regular. That's why 11.6 compression is very reasonable in this bike. Knocking is not just a function of compression but also of head temperature, squish volume, cylinder size (i.e. flame front travel time), valve and ignition timing, etc.

Long story short, 11.6 compression will require high test in an aircooled ducati because of it's bigger pistons and less efficient head cooling, but in a cbr600 87 octane will work great.

I rather spend a couple cents more at the tank for a higher grade fuel that is more cooler of a burn than a hotter burn like 87. If it gets hot outside and your running that bike hard with a lower grade fuel you could get denotation. On my z with advance ignition and with a 9.6:1 I run 91 or higher and this is a less aggressive motor than these bikes. Other wise denotation will come back and haunt you. Seen it on the GTO and several other things. 4 stroke is a 4 stroke.

well a quick google revealed that you are correct in the AKI - RON statement

I will check my manual once I get home if its correct... $$ savin time !

With 87 octane you are going to have a ton of carbon deposits. Won't flow efficently. I still won't run less than 89 ever, especially in summer.
93 can help clean the carbs too.

Regular (Car) Mobil1 is liable to cause clutch slippage. If you want to use Mobil1, gotta go with the bike blend as it doesn't have the additives that will react badly with a wet clutch. Another option is Shell Rotella Synthetic (truck grade oil, $25-$30/Gal at walmart), which doesn't contain the additives that normal car oils do.

I've been using Castrol Act-Evo synthetic blend (4.99/qt at Cycle Gear), it's really held up well.

If your not knocking or getting detonation with 87 octane, you won't build carbon any more than with higher octane gas. Some companies put more detergent in their higher octane gases, but that's a different issue. Regardless of what gas you put in your tank, if you don't start it up every 2 weeks you will gum up those carbs.

If it gets hot outside, it can make your bike need high test more. However, unless you're drag racing and doing power up wheelies in the sahara in the middle of summer, I don't think it's necessary.

If you really insist on putting premium in the tank, go ahead. It's just not going to do anything for you on a stock motor.

very bad lol. remember being told something about av fuel not being the same as reg gas or race fuel even. We use to run it in the sand rails etc, but we tore those engines down every couple years just cause lol.