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why do Cr's love race fuel

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why dose everyone say that Cr's love race fuel ..or it needs race fuel to not detonate or yea it comes alive with race gas

i have a 2001 cr250 and run 50/50 VP C12/ mobil pump 93

yea my bike runs good but i don't think it needs race fuel, why would the desgin a bike to only run good on race fuel

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why dose everyone say that Cr's love race fuel ..or it needs race fuel to not detonate or yea it comes alive with race gas

i have a 2001 cr250 and run 50/50 VP C12/ mobil pump 93

yea my bike runs good but i don't think it needs race fuel, why would the desgin a bike to only run good on race fuel

I think that phrase mostly comes from the 05-07 guys who say they needed high octane fuel to kept from detonating on their stock engines.

I run a 50/50 mix of 91 and 100 octane. It didn't detonate using 91, but I heard so many negatives about detonation with the sst I started running the 50/50 mix. Like I said, my experience with the 2nd Gen cr is that they do not require anything higher than the 92 spec'd in the manny, may even try the 91 with the sst :thumbsup:

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i run 93 and my bike runs perfect. anything over that is just a waste of money unless your bike is detonating but if its stock it shouldnt be at 93. i always heard your supposed to run the lowest octane you can without detonation

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I saw the same nonsense in hot rods. You smell race fuel coming from a kids Mustang, and you ask "What compression ratio?", answer "Stock". "Why you running 99?", "More Performance".

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Many people live in areas where ethanol is mixed in the fuel. Race gas is at least consistent and ethanol free. This is why I use race fuel.

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If you have a quality source of pump gas that doesn't detonate, your fine. I can't find a fuel in my area that works, they all have ethanol, and detonate like crazy even in my stock motor. Some cr.'s have issues with the cyl head, this may play a role as well. Some race fuels provide a hp increase even in unmodified applications, others don't. Mxa did a write up a while back on this.

I like c12, it provides a very consistent base for the very picky mikuni, totally eliminates detonation in my machine and doesn't stink up the house like the MR2. I do drain the carb after each ride though, the only drawback.:thumbsup:

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you do realize ethanol will help keep your bike from detonating? It's just bad for the carb if you let it sit in there. second I don't care what anybody says, your bike will make less power on race gas than on pump gas if you have stock compression. this is why GXSR600s make more hp on 87 octane than 93 octane. you want to run the lowest octane you can without detonating.

Edited by sled

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If you have a quality source of pump gas that doesn't detonate, your fine. I can't find a fuel in my area that works, they all have ethanol, and detonate like crazy even in my stock motor. Some cr.'s have issues with the cyl head, this may play a role as well. Some race fuels provide a hp increase even in unmodified applications, others don't. Mxa did a write up a while back on this.

I like c12, it provides a very consistent base for the very picky mikuni, totally eliminates detonation in my machine and doesn't stink up the house like the MR2. I do drain the carb after each ride though, the only drawback.:thumbsup:

Why do you drain your carb? C12 is not a corrosive fuel like U4 is. The U4.2 and U4.4 you should remove from your bike following a race, but C12 and other high octane leaded fuels like Cam2 110 you don't have to worry about. I have used both in my son's super mini which has a high compression motor and requires the high octane. I dont drain the carb bowl and never had a problem with jets getting clogged or anything else.

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Why do you drain your carb? C12 is not a corrosive fuel like U4 is. The U4.2 and U4.4 you should remove from your bike following a race, but C12 and other high octane leaded fuels like Cam2 110 you don't have to worry about. I have used both in my son's super mini which has a high compression motor and requires the high octane. I dont drain the carb bowl and never had a problem with jets getting clogged or anything else.

I let the bike sit for a few weeks , and it gummed up on me. That and the big"drain carb after every use" sticker on the c12 can.

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I let the bike sit for a few weeks , and it gummed up on me. That and the big"drain carb after every use" sticker on the c12 can.

I guess I've been lucky. I use Star Tron fuel treatment in my bike, but that's for pump gas.

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I sure hope that startron stuff works, something has been giving my carb jets(pilot) fits lately. Keep finding a gummy residue. And I truly believe my CR250 is running worse on the ethanol gas. In my three autos I am getting less mileage also.

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I've been using Star Tron and love the stuff. I also put it in every new batch of fuel I buy before putting it in my bike. My local motorcycle performance shop sells it and highly recommends it over stabil. A bottle goes a long way also.

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race gas has a much longer shelf life than pump gas so it should not be gumming up your carb. thats more probably due to the brand of 2 stroke oil your using. My banshee sits most of the year and I've never had that problem. I run it on vp c16.

your bike maybe running worse because it needs to be rejetted. eithanol burns at a much faster rate which is why your mpg has dropped. I'n not saying eithanol is good for our bikes, but it's not bad for performance. it does kill fuel lines, fuel valves, and carbs.

Edited by sled

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second I don't care what anybody says, your bike will make less power one race gas than on pump gas if you have stock compression. this is why GXSR600s make more hp on 87 octane than 93 octane. you want to run the lowest octane you can without detonating.

does that statement take oxygenated race fuels into account?

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does that statement take oxygenated race fuels into account?

you got me there. no, it does not include them. I forget about them because I never use them. you can't just put that in any old bike though and not rejet it. also, do NOT let that sit in your bike if you use it!

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