Help me understand fuels

navalseabee
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navalseabee
Edited Date/Time 8/20/2020 9:04pm
So I am a bit ignorant as to what all the numbers on the spec sheet mean but looking at Octane and O2 levels they're very close, so I am trying to understand what justifies the extra costs associated with U 4.4 and MRX02 versus T2 and what makes one better than the other.



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AJ565
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AJ565 8/18/2020 6:04pm
8/18/2020 6:04pm
U4.4 makes the most power of the 3. T2 makes the least, but still more then pump or C12 because of the oxygen content and it comes premixed 40:1.

MRX02 is AMA legal and u4.4 is not. All 3 are excellent fuels and you’ll notice a difference going from pump to any of them. I was running u4.4 when I was able to get it at $65/5gal which was the same price as T2. The shop went out of business and I wasn’t paying $100 for it.

On track I wasn’t able to tell a difference between T2 and u4.4 other then the exhaust smell is different.
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navalseabee
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navalseabee 8/19/2020 2:28am
8/19/2020 2:28am
AJ565 wrote:
U4.4 makes the most power of the 3. T2 makes the least, but still more then pump or C12 because of the oxygen content and it...
U4.4 makes the most power of the 3. T2 makes the least, but still more then pump or C12 because of the oxygen content and it comes premixed 40:1.

MRX02 is AMA legal and u4.4 is not. All 3 are excellent fuels and you’ll notice a difference going from pump to any of them. I was running u4.4 when I was able to get it at $65/5gal which was the same price as T2. The shop went out of business and I wasn’t paying $100 for it.

On track I wasn’t able to tell a difference between T2 and u4.4 other then the exhaust smell is different.
Right on I appreciate it, so it pretty much just the O2 content that makes up the difference in power potential? I would also guess AMA legal stamp is helping drive up the price there on the MRX.
newmason
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newmason 8/19/2020 6:02am
8/19/2020 6:02am
Ones green, the other is blue. Blue always goes faster
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kkawboy14
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kkawboy14 8/19/2020 6:10am
8/19/2020 6:10am
1 thing people don’t realize is that pump fuel changes chemistry from winter to summer. Pump fuel has the possibility of having more water in it. Pump fuels can be more dirty.

Reverse all 3 of those and that’s why I run T-4
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omalley
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omalley 8/19/2020 6:14am
8/19/2020 6:14am
kkawboy14 wrote:
1 thing people don’t realize is that pump fuel changes chemistry from winter to summer. Pump fuel has the possibility of having more water in it...
1 thing people don’t realize is that pump fuel changes chemistry from winter to summer. Pump fuel has the possibility of having more water in it. Pump fuels can be more dirty.

Reverse all 3 of those and that’s why I run T-4
Agreed.

Pump fuel (today) is garbage.
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huutnanny
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huutnanny 8/19/2020 6:56am
8/19/2020 6:56am
Fuels don’t necessarily make more power. You need a motor that needs high octane to make more power. (Compression, timing, etc...) So if you have a 2 stroke, there’s probably a sweet spot between pump gas and 100+ octane that works pretty well. If it’s mostly stock, no way you need 100+ octane. And some of those race fuels can be actually worst for wear as they have some additives that are not necessarily friendly to your motor internals.
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Rickyisms 8/19/2020 8:23am
8/19/2020 8:23am
huutnanny wrote:
Fuels don’t necessarily make more power. You need a motor that needs high octane to make more power. (Compression, timing, etc...) So if you have a...
Fuels don’t necessarily make more power. You need a motor that needs high octane to make more power. (Compression, timing, etc...) So if you have a 2 stroke, there’s probably a sweet spot between pump gas and 100+ octane that works pretty well. If it’s mostly stock, no way you need 100+ octane. And some of those race fuels can be actually worst for wear as they have some additives that are not necessarily friendly to your motor internals.
My stock 125 has been very happy with leaded 110 for many many hours.
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Rickyisms 8/19/2020 8:25am
8/19/2020 8:25am
I tried U4.4 in a modded two stroke and it ran worse because I didn’t mess with jetting and the oxygen content was much higher than my previous fuel. I ran the T2 for a while and I liked it but I’m a 927 guy so I switched the 927+C12 in my mod bike and 927+110 in my stock bike.
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mxb2
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mxb2 8/19/2020 8:33am
8/19/2020 8:33am
AJ565 wrote:
U4.4 makes the most power of the 3. T2 makes the least, but still more then pump or C12 because of the oxygen content and it...
U4.4 makes the most power of the 3. T2 makes the least, but still more then pump or C12 because of the oxygen content and it comes premixed 40:1.

MRX02 is AMA legal and u4.4 is not. All 3 are excellent fuels and you’ll notice a difference going from pump to any of them. I was running u4.4 when I was able to get it at $65/5gal which was the same price as T2. The shop went out of business and I wasn’t paying $100 for it.

On track I wasn’t able to tell a difference between T2 and u4.4 other then the exhaust smell is different.
navalseabee wrote:
Right on I appreciate it, so it pretty much just the O2 content that makes up the difference in power potential? I would also guess AMA...
Right on I appreciate it, so it pretty much just the O2 content that makes up the difference in power potential? I would also guess AMA legal stamp is helping drive up the price there on the MRX.
Its leaded, not ama legal
4DAIVIPAI2K5
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4DAIVIPAI2K5 8/19/2020 8:46am
8/19/2020 8:46am
kkawboy14 wrote:
1 thing people don’t realize is that pump fuel changes chemistry from winter to summer. Pump fuel has the possibility of having more water in it...
1 thing people don’t realize is that pump fuel changes chemistry from winter to summer. Pump fuel has the possibility of having more water in it. Pump fuels can be more dirty.

Reverse all 3 of those and that’s why I run T-4
That's why I run av gas for my son. Plus it's half mile away. Right around $4/gallon.
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huutnanny
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huutnanny 8/19/2020 9:16am
8/19/2020 9:16am
huutnanny wrote:
Fuels don’t necessarily make more power. You need a motor that needs high octane to make more power. (Compression, timing, etc...) So if you have a...
Fuels don’t necessarily make more power. You need a motor that needs high octane to make more power. (Compression, timing, etc...) So if you have a 2 stroke, there’s probably a sweet spot between pump gas and 100+ octane that works pretty well. If it’s mostly stock, no way you need 100+ octane. And some of those race fuels can be actually worst for wear as they have some additives that are not necessarily friendly to your motor internals.
Rickyisms wrote:
My stock 125 has been very happy with leaded 110 for many many hours.
I think the issues stem from the oxygenated part. Leaded fuels are generally a positive for motor internals although in a 2 stroke with the absence of valves I think the advantages are probably small.
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skeef
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skeef 8/19/2020 9:36am
8/19/2020 9:36am
Okay I have questions then, If I only run race gas sometimes is that bad for the bike?

Generally can race gas be ran under any conditions ie: elevation, temp?

I have a bone stock 2020 450xcf and I want to run race fuel.
Rickyisms 8/19/2020 9:39am
8/19/2020 9:39am
skeef wrote:
Okay I have questions then, If I only run race gas sometimes is that bad for the bike? Generally can race gas be ran under any...
Okay I have questions then, If I only run race gas sometimes is that bad for the bike?

Generally can race gas be ran under any conditions ie: elevation, temp?

I have a bone stock 2020 450xcf and I want to run race fuel.
In a bone stock 4 stroke I would be leaning towards T4. It wouldn’t hurt to run it occasionally but to stay more consistent I would cut T4 and premium pump half and half.
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mxb2
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mxb2 8/19/2020 9:47am
8/19/2020 9:47am
skeef wrote:
Okay I have questions then, If I only run race gas sometimes is that bad for the bike? Generally can race gas be ran under any...
Okay I have questions then, If I only run race gas sometimes is that bad for the bike?

Generally can race gas be ran under any conditions ie: elevation, temp?

I have a bone stock 2020 450xcf and I want to run race fuel.
Rickyisms wrote:
In a bone stock 4 stroke I would be leaning towards T4. It wouldn’t hurt to run it occasionally but to stay more consistent I would...
In a bone stock 4 stroke I would be leaning towards T4. It wouldn’t hurt to run it occasionally but to stay more consistent I would cut T4 and premium pump half and half.
Run t4 staight. No need to mix it. It is a pump replacement.
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Hasletjoe
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Hasletjoe 8/19/2020 9:52am
8/19/2020 9:52am
I run the C12 in my vintage bikes. As the pump Ethanol will ruin the fiberglass tanks. The other side is that my British bikes start in 1-2 kicks, always. That in itself is worth the extra cost. Laughing
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Rickyisms 8/19/2020 10:08am
8/19/2020 10:08am
Hasletjoe wrote:
I run the C12 in my vintage bikes. As the pump Ethanol will ruin the fiberglass tanks. The other side is that my British bikes start...
I run the C12 in my vintage bikes. As the pump Ethanol will ruin the fiberglass tanks. The other side is that my British bikes start in 1-2 kicks, always. That in itself is worth the extra cost. Laughing
I ran C12 when I raced an old IT175 a couple times.
navalseabee
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navalseabee 8/19/2020 10:31am
8/19/2020 10:31am
The motor in my 150 is modified, porting and head work. The builder recommended at a minimum T2, I’m curious if there’s more to give there with fuel alone.
ZB93
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ZB93 8/19/2020 10:35am
8/19/2020 10:35am
Call VP Southeast at 954-565-7670

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mx216
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mx216 8/19/2020 11:06am
8/19/2020 11:06am
huutnanny wrote:
Fuels don’t necessarily make more power. You need a motor that needs high octane to make more power. (Compression, timing, etc...) So if you have a...
Fuels don’t necessarily make more power. You need a motor that needs high octane to make more power. (Compression, timing, etc...) So if you have a 2 stroke, there’s probably a sweet spot between pump gas and 100+ octane that works pretty well. If it’s mostly stock, no way you need 100+ octane. And some of those race fuels can be actually worst for wear as they have some additives that are not necessarily friendly to your motor internals.
Rickyisms wrote:
My stock 125 has been very happy with leaded 110 for many many hours.
A stock 125 doesn't have the compression or timing to warrant running 110. You are losing power and wasting money by running it, but I bet it smells good!
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navalseabee
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navalseabee 8/19/2020 12:17pm
8/19/2020 12:17pm
ZB93 wrote:
Call VP Southeast at 954-565-7670
Best advice, Zack talked to me for 25 minutes about these fuels and what everything means. Good stuff.
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philG
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philG 8/19/2020 12:47pm
8/19/2020 12:47pm
navalseabee wrote:
The motor in my 150 is modified, porting and head work. The builder recommended at a minimum T2, I’m curious if there’s more to give there...
The motor in my 150 is modified, porting and head work. The builder recommended at a minimum T2, I’m curious if there’s more to give there with fuel alone.
Better quality fuel allows you to run a edgier motor with less risk, as it runs cooler. So you can run compression that you could never run on regular gas.
AJ565
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AJ565 8/19/2020 3:17pm
8/19/2020 3:17pm
AJ565 wrote:
U4.4 makes the most power of the 3. T2 makes the least, but still more then pump or C12 because of the oxygen content and it...
U4.4 makes the most power of the 3. T2 makes the least, but still more then pump or C12 because of the oxygen content and it comes premixed 40:1.

MRX02 is AMA legal and u4.4 is not. All 3 are excellent fuels and you’ll notice a difference going from pump to any of them. I was running u4.4 when I was able to get it at $65/5gal which was the same price as T2. The shop went out of business and I wasn’t paying $100 for it.

On track I wasn’t able to tell a difference between T2 and u4.4 other then the exhaust smell is different.
navalseabee wrote:
Right on I appreciate it, so it pretty much just the O2 content that makes up the difference in power potential? I would also guess AMA...
Right on I appreciate it, so it pretty much just the O2 content that makes up the difference in power potential? I would also guess AMA legal stamp is helping drive up the price there on the MRX.
mxb2 wrote:
Its leaded, not ama legal
Its not legal for AMA pro racing like supercross and nationals.

MRX02 is an oxygenated, leaded, 104-octane, two-stroke fuel. It sells for $168 (per 5 gallons). If you had a high-strung 250SX engine instead of a stocker with a pipe, MRX02 would be the best-performing two-stroke motocross fuel to use. Because it is oxygenated, it delivers up to 7 percent more power than pump gas or non-oxygenated race fuel, but costs more than $30 a gallon.

T2 is a non-oxygenated, leaded, 105-octane two-stroke fuel that is already pre-mixed with two-stroke oil at 40:1. It sells for $60 (per 5 gallons of pre-mix).

U4.4 is an oxygenated, leaded, 108.5-octane two- and four-stroke fuel. Unlike MRX02, U4.4 is not legal in AMA racing but can be used in local racing. It does require larger main and pilot jets. It sells for $78 (per 5 gallons).

https://motocrossactionmag.com/amp/ask-the-mxperts-race-gas-is-much-too…
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Jonesboys819_828 8/19/2020 3:53pm
8/19/2020 3:53pm
kkawboy14 wrote:
1 thing people don’t realize is that pump fuel changes chemistry from winter to summer. Pump fuel has the possibility of having more water in it...
1 thing people don’t realize is that pump fuel changes chemistry from winter to summer. Pump fuel has the possibility of having more water in it. Pump fuels can be more dirty.

Reverse all 3 of those and that’s why I run T-4
4DAIVIPAI2K5 wrote:
That's why I run av gas for my son. Plus it's half mile away. Right around $4/gallon.
What are you running AC gas in, if mixed what do you mix it. I’ve always understood that AC gas is a very dry fuel and designed for aircraft engines specially because of altitude. Just asking as there’s an small local Airport near me.
sesker15
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sesker15 8/19/2020 4:34pm
8/19/2020 4:34pm
AJ565 wrote:
Its not legal for AMA pro racing like supercross and nationals. MRX02 is an oxygenated, leaded, 104-octane, two-stroke fuel. It sells for $168 (per 5 gallons)...
Its not legal for AMA pro racing like supercross and nationals.

MRX02 is an oxygenated, leaded, 104-octane, two-stroke fuel. It sells for $168 (per 5 gallons). If you had a high-strung 250SX engine instead of a stocker with a pipe, MRX02 would be the best-performing two-stroke motocross fuel to use. Because it is oxygenated, it delivers up to 7 percent more power than pump gas or non-oxygenated race fuel, but costs more than $30 a gallon.

T2 is a non-oxygenated, leaded, 105-octane two-stroke fuel that is already pre-mixed with two-stroke oil at 40:1. It sells for $60 (per 5 gallons of pre-mix).

U4.4 is an oxygenated, leaded, 108.5-octane two- and four-stroke fuel. Unlike MRX02, U4.4 is not legal in AMA racing but can be used in local racing. It does require larger main and pilot jets. It sells for $78 (per 5 gallons).

https://motocrossactionmag.com/amp/ask-the-mxperts-race-gas-is-much-too…
Never quote MXA lol.
T2 is an oxygenated fuel also. With a oxygen content of 5.94.
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navalseabee
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navalseabee 8/19/2020 5:07pm
8/19/2020 5:07pm
Lets shift gears a bit and bikes.

To take advantage of what these oxygenated fuels have to offer you have to remap the bike i understand that, question is does the Yamaha Power Tuner App have enough flexibility to take advantage or do you have to go full Vortex/GET?
huutnanny
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huutnanny 8/19/2020 6:21pm
8/19/2020 6:21pm
navalseabee wrote:
Lets shift gears a bit and bikes. To take advantage of what these oxygenated fuels have to offer you have to remap the bike i understand...
Lets shift gears a bit and bikes.

To take advantage of what these oxygenated fuels have to offer you have to remap the bike i understand that, question is does the Yamaha Power Tuner App have enough flexibility to take advantage or do you have to go full Vortex/GET?
I think the tuner app only sets safe conditions. I think on some of those more aggressive maps their maybe some gains.

The thing that kinda make me laugh is avoiding pump gas with ethanol fuel and then buying oxygenated race gas.
AJ565
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AJ565 8/19/2020 9:33pm
8/19/2020 9:33pm
sesker15 wrote:
Never quote MXA lol.
T2 is an oxygenated fuel also. With a oxygen content of 5.94.
Lol I didn’t pay attention to the T2 stuff on that one. I had VP’s site open with all 3 fuels and the mxa was easier to copy and paste.
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navalseabee
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navalseabee 8/20/2020 2:15am
8/20/2020 2:15am
navalseabee wrote:
Lets shift gears a bit and bikes. To take advantage of what these oxygenated fuels have to offer you have to remap the bike i understand...
Lets shift gears a bit and bikes.

To take advantage of what these oxygenated fuels have to offer you have to remap the bike i understand that, question is does the Yamaha Power Tuner App have enough flexibility to take advantage or do you have to go full Vortex/GET?
huutnanny wrote:
I think the tuner app only sets safe conditions. I think on some of those more aggressive maps their maybe some gains. The thing that kinda...
I think the tuner app only sets safe conditions. I think on some of those more aggressive maps their maybe some gains.

The thing that kinda make me laugh is avoiding pump gas with ethanol fuel and then buying oxygenated race gas.
Who said I was avoiding pump fuel. Vital cracks me up.
Rickyisms 8/20/2020 6:30am
8/20/2020 6:30am
ZB93 wrote:
Call VP Southeast at 954-565-7670
navalseabee wrote:
Best advice, Zack talked to me for 25 minutes about these fuels and what everything means. Good stuff.
If it's the same Zack I know from VP he's a good dude. He's our VP rep and really knows his shit.

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