Hey Rich, VP Racing Fuel

[ChopperDave]

Hey Rich, I can't get the Track Tech101 fuel you told me about, smallest qty. the local oil co sells is 55gal drum. To much considering the storage issues you mentioned. My local bike dealer has several grades of VP Racing Fuel. Would these be comparable to the TT101. Is it worth using instead of pump gas?

 

[ChopperDave]

So after many searchs, and much reading, it seems that C-12 is good general purpose fuel for my CRF250X. Unless anyone, Rich, has any serious objections I will try it and check the plug/jetting.

I didn't see any mention of VP Red? Anyone have any knowledge of this stuff?

 

[Rich Rohrich]

Dave - VP Red is a very POOR choice for the CRF250X. Not a bad fuel for a low rpm big block Chevy, but a horrible choice for the 250X. C12 is a very nice all around fuel. Easy to jet, fairly cheap, great throttle response. You might also want to take a look at U4. I haven't played with it personally, but lots of folks seem to like it and the basic spec looks good.

 

[ChopperDave]

Thanks Rich! I will prolly try the C-12 first. It is $43.50 a can, compared to $60 for the U4. 5gals.

 

[Rich Rohrich]

Dave = Keep in mind that C12 will run a lot richer than pump fuel. The 250X comes jetted pretty lean from the factory but you still might end up having to do some carb fiddling.

 

[ChopperDave]

So I will have to lean the jets for C-12? Thats OK, I just Don't want to be doing that alot(re-jetting!)!!!! That carb is hard to get to! I don't race, just looking for a little more power, and something that burns cleaner for the valve life. My wife wants me to race Hare Scrambles! I want to also, but I will need all the help I can get. Even if it is from a mild race fuel. I'm thinkin' the 250X was born for Hare Scrambles!

Thanks again Rich! It takes a person who really enjoys the sport, to freely share info, and that is certainly YOU!

 

[Rich Rohrich]

Dave - For the record, the fuel isn't going to help valve life so forget about that. There is a bit more power and a lot more throttle response to be had from C12 once it's jetted right but if you are looking for more power as a justification for the money spent you'll need to go with an oxygenated fuel like TT101 or from VP MR9,MR8, MR1 or U4 (not U4e).

 

[ChopperDave]

So the U4 would justify the cost=valve life?

 

[ChopperDave]

Would the U4 run well with the stock jets. Seems like it would with the O'2 added. To me it would be worth the extra cost (versus C-12) not to have to re-jet. And in an emergency, I could still run pump gas if I had to.

 

[ChopperDave]

I feel like such a NOOB!!!! :ahhh:

 

[MikeS]

Would the U4 run well with the stock jets. Seems like it would with the O'2 added. To me it would be worth the extra cost (versus C-12) not to have to re-jet. And in an emergency, I could still run pump gas if I had to.

NO, You will need bigger jets and a different needle position or needle. A stock 250X has around a 142 main and our 250X with the air box opened up and U4 we run 165 -175 main depending on the temps.

Cost to rejet ??? As Rich mentioned the stock bike is off the mark with pump gas in most cases. Some jets and a needle will set you back $30-$60. the JD Jetting kit out there is good for the novice tuner as it is a no brainer. Good instructions but it is based on pump gas.

Try C12 first as the jetting should be close, With U4 you must re jet from stock.

Good luck

 

[Rich Rohrich]

So the U4 would justify the cost=valve life?

None of these fuel will extend valve life so forget about that. As Mike pointed out , changing fuels will usually involve changing jets but it's worth it. :nod:

 

[mtk]

Rich,

How does VP C-12 compare to Sunoco Supreme, aka "Blue" race fuel?

I had my 2002 CR250 ported with a "Mo Betta" port job, set up for pump gas, but I got some detonation with the new set-up. I switched to Sunoco "Blue" and that solved the detonation problem, so it looks like race fuel is the ticket from now on. I'll probably send the head back in the fall to be set up for race fuel since I have to run it anyway. At any rate, I'd like to hear your thoughts on the Sunoco versus VP fuels. A local dealer sells 5-gallon cans of VP C-12 for $42, but I can get the Sunoco for $4.69/gallon at a local station, so it's not only cheaper but more available since the gas station has much better hours of operation. What do you think?

 

[Rich Rohrich]

Sunoco Supreme Blue will work fine, the problem is buying it from a bulk storage ground tank puts a degree of variability in the fuel that makes it a poor value in my mind. If it's working and you are happy with the performance, then I wouldn't worry about it. ;)