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Renegade MX4 may not be as much of a household racing fuel name with normal blue collar folk as VP Racing. With that being said, I think some of this is because it’s tougher to find Renegade fuels than VP and lets face it, VP has some pretty damn good fuel. However, Renegade offers several different kinds of fuel for the two wheeled enthusiast at a competitive price as well. I wanted to try a pump replacement fuel, similar to VP’s T4, so I asked a Renegade dealer Stan Benson Racing (located in up in Northern California) to supply me with a pale of MX4 (we also will be reviewing Renegade’s SX4+ in a future article). This high-performance four-stroke-specific fuel has many of the same technologies as Renegade’s popular SX4+ fuel and is also used by many top AMA Supercross teams. In most cases, MX4 is said to not require jetting or fuel mapping changes when transitioning from pump fuel applications. Renegade’s in house testing has shown up to 4-5% gains in power over popular comparable fuels on the market and their exclusive additive package is said to inhibit dreaded gumming and performance-robbing deposits. Much better than our crappy California blend fuel!
The biggest advantage of MX4 over pump gas is that our current California crappy pump gas contains ethanol, an alcohol-based alternative fuel manufactured by fermenting and distilling starch crops that have been converted to simple sugars. This is not good for the lifespan of valve trains, fuel pumps, and top end gaskets on small engines like those found in dirt bikes. Ethanol in the fuel can leave a gummy substance that clogs fuel pumps (or jets on carbureted bikes) and causes early deterioration of head gaskets and o-rings, shortening the life of your engine. Another major problem is phase separation; if water gets into the fuel, this can cause the water/ethanol mixture to sink to the bottom of the tank where the fuel pickup is. Water inside your engine can cause the fuel pump to stop working and also can make your bike miss and sputter.
Is the on-track performance gain from MX4 worth the added cost from pump? For the average guy screwing around on open land, maybe not so much. For the true enthusiast who rides/races hard and wants a reliable power gain? Yes, it is, at least to me. Renegade’s MX4 comes in an easy-to-pour 5-gallon pail or a 55-gallon drum. I ran a pale of MX4 through a KTM 450 SX-F, YZ450F and CRF250R and it took me less than two laps to feel the added throttle response compared to pump fuel. When I came out of corners, while rolling the throttle on in second gear, each machine had more pull down low as well as throttle response with the MX4. In third gear, I felt a better pull and each machine ran crisper/cleaner throughout the rpm range. I didn’t feel too much gain through the top-end as most of what I felt was down low and up through the midrange. An added benefit was that the bike was easier to start (this especially is great because the YZ450F was the hardest to start out of all the machines I tested the fuel with). Riding longer motos on a sandier-type track, I also noticed that the bike kept consistent power. Usually when I test at this type of track, the power falls off a little as the bike gets hot with pump fuel—but not so with MX4. I also liked that I didn’t have to change my ECU mapping in either a stock ECU’s or a previously mapped Vortex ECU.
Compared to VP’s T4 I feel like both are similar in performance on the track except for one area. Renegade’s MX4 does give a better low end rpm response, but pulling power down low feels similar. Renegade has a slightly cleaner feel on low rpm, but I wouldn’t know that everyone would be able to feel the difference when going back to back with each fuel.
For $94.00 for a five gallon pale of MX4, it is a little more expensive than that of T4, but there is a small performance advantage. Is it worth it? That will have to be left up to you, but it’s nice to know that the consumer has another option when it comes to pump replacement race fuel. You can order your Renegade Race Fuels right here: