Anybody know why the new VP U4.2 fuel has to be taken out every week after running? I contacted VP but don't have any answer yet.

Anybody know why the new VP U4.2 fuel has to be taken out every week after running? I contacted VP but don't have any answer yet.
vrd65,
I run a couple different VP Race Fuels{ M-5 and C-16},and have heard lots of different ways of dealing with the Methanol,but U4 is one of their new Oxygenated Fuels ,and it might have something to do with that:wazzup: ? I used to Race with NUTEC,and my Mechanic would make me drain out the fuel before he worked on it because the Fumes were so BAD it would give him a Migraine Head ache:hidesbeh: ! I have the Head of VP Fuels BAT LINE if it's Life or Death let me know:kaz: .

There were 2 problems with U4. One was that it left a sticky residue in the fuel system if left in to more that a few days. THe other was the fact that if it was not is a sealed container, it would start to lose it's oxygenation.

U4.2 takes care of the first problem, but if you leave it in the tank too long it will lose some of it oxygen and you tune will become rich and not develop as much power.

I can't tell you how much it degrades over what amount of days, but I have left it in for a week or so and it seemed to be fine.

There were 2 problems with U4. One was that it left a sticky residue in the fuel system if left in to more that a few days. THe other was the fact that if it was not is a sealed container, it would start to lose it's oxygenation.

U4.2 takes care of the first problem, but if you leave it in the tank too long it will lose some of it oxygen and you tune will become rich and not develop as much power.

I can't tell you how much it degrades over what amount of days, but I have left it in for a week or so and it seemed to be fine.
:them:

I heard from VP fuels today and they said it's Ok to leave it in. The label is more for liability than anything. But thanks for responding, I appreciate it.

I've used VP U4.2 and left the stuff in the tank for about 1 month with no "apparent" problems. I haven't used the old sticky U4 so I can't compare but it is always better to keep the fuel in a sealed container to stop the fuel loosing the "light ends" (more volatile components of the fuel blend.)

While we're on the subject of fuel does anyone have the stock International map for VP C25 fuel???? (I may just want to try the stuff)

V&H motorsport have a map on their website to suit their Indy exhhast system but I'm looking for the stock C25 map if possible.

H-D released this as TT247 – June 30, 2006 - Destroyer C-25 calibration for International markets. I haven't found this yet.

Hopefully someone has it, ...don't make me have to go the the H-D Dealer and beg!

One of the other problems with leaving it in the tank is that your tank is plastic. Plastic has pores and a VP rep told me this:
That if you leave U4 or U4.2 in the V-rod tank that it will loose its oxygen in just a day or two. He also told me that is why it is in metal containers and has a plastic liner. U4 and U4.2 will loose its kick if it is in direct sun light.