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Fuel Factory is good stuff, no complaints from the car guys around here. Sunoco is usually my go to choice for anything that needs extra octane.
Where did you get the o-rings ? Do you have a part number by chance?
When I lived out west I ran E-10 all the time without issues. I moved out East where we have humidity and instantly started having issues with my pilot jets clogging. The ethanol pulls moisture from the air and it will corrode the brass, green and white crystals all over the float bowl.
Yup, had a mechanic check how my intake valves look, he said there was a thin layer of black soot around the channels, not on the valves. The fuel pump was also not working to spec in terms of maintaining pressure. I’m really hoping VP pays for this, between the fuel pump and checking into the valves this isn’t cheap, plus the wasted money on VP over the last 6 months. I’m running 94 from Sunoco or 93 from Wawa from now on.
I am super picky with how I wash my bike, I use the good Motul oil, new oil filters every oil change (4-6 hours), and new twin air filters whenever it’s dirty. The bike only has 30 hours and I am a joy vet rider. I know we can’t blame everything on fuel but this seems obvious.
Anyone have a fuel cleaner they suggest? Mechanic said that should clean up the valves.
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Some guys I drag race with use it. They have good results. I don't use it simply because their Q16 equivalent isnt quite close enough for my liking.
So, youre the only one that got this "mystery blend" of fuel? Sounds like a load of "my friend told me" information. What really happened here was your carb KTM was jetted too lean. I cant wait to hear how many other people on this forum have had issues with pump gas "not blending with synthetic oil", ill bet theres none besides you. But hey, its your story, feel free to tell it how you want. Most people know the real truth here.....
Not trying to add to the fuel war happening here, but it’s worth remembering that West Coast gas isn’t the same as what you guys get back East. California-spec 91 is reformulated for emissions, has less energy content, more sulfur, and tends to run hotter and less stable in high-compression MX engines. majority of us are not chasing horsepower… we just want consistent combustion and zero flame-outs because let’s face it the flame outs won’t happen idling through the pits but at the worst time on the face of a jump. The fuels are just different in NJ, that’s all, and it’s awesome that it works well for you guys but that isn’t available here and we are forced to search for something that works consistently.
Thats what I have heard aswell and I have seen it before in bikes ive worked on but the bikes ive maintaine for people and my own have always been fine. Im in the midwest so we have tons of humidity to. Guess im either lucky or doing something right without even knowing it. lol
Just thought I would put this article from Keefer Inc up for a read if anyone is interested:
https://www.keeferinctesting.com/2020-3-11-questions-about-av-gas-answe…
Sadly that massive article is a miss.
Hook it up to a 9v battery and attach pressure test gauge. I think most modern 450s are supposed to kick 40-50 PSI
https://youtu.be/J5V4SUJei_w?si=iynjzy2TqsgSeCgY
I don’t have part numbers but my dealer had some that worked.
I had ethanol eat up the fuel line on a 99 YZ400. The bike had to sit from work and a minor crash for about 3 months. When I went to start it I drained it and put fresh gas in it and it wouldn't start. When I pulled the carb the fuel line felt mushy. I cleaned the carb and spent hours fucking with it and eventually took it to a dealer to soak in their hot tank. When it came out the parts guy said a black goo came out when he blew it out with air. No problems after that and now I only run Motion Pro eth safe fuel line.
Do you think the T4+ damaged your fuel pump? Shit happens but as far as T4+ goes, I hope VP figures it out. I've been running T4 in my FC 450 since about 6 months after I got it. The last time I ran pump gas it ran like shit but that is California gas.
Replaced the MAP sensor, fuel pump and filter, cleaned the throttle body. Pump gas and some injector cleaner and we should be good.
What do you mean a miss?
It’s like 85% about nothing to do with avgas and the 15% that is about avgas is wrong, irrelevant, or a waste of time.
Avgas is leaded, clean, highly tested for water and purity, very consistent, no ethanol, and higher octane than pump gas.
It has a lower specific gravity than pump fuel. That requires richer jetting or tuning.
You can run a blend of 100ll to pump gas and get the specific gravity closer to normal pump fuel, would recommend the highest octane ethanol free you can find but personally I just ran the 100ll straight as the entire point was consistency and the purity.
You have to rejet.
All the issues around it are just pouring it in and expecting it to run with the same settings….
But these elementary level articles on it don’t even speak on that.
https://bobistheoilguy.com/forums/threads/100ll-race-gas-interesting-read.238415/
Here’s a real discussion around it. If you read the first post ignore the “key points summary at the top” that guy got the flame speed wrong. The actual body of the discussion he copied and pasted and it addresses that avgas curves closely match traditional race fuels and don’t burn too slow or too fast or any imaginary bs.
One last thing from my previous nerding out about 100ll research in the past: the low specific gravity effects some oils ability to premix in cold weather specifically castor oils.
I used 927 castor oil in 100ll exclusively and never had issues but rarely/never ride below 50 degrees Fahrenheit. So if you’re a 2 stroke guy and love 927 and love the cold weather , beware it can seperate. That’s where you’d want to mix with pump gas to get a higher specific gravity.
I’d either just avoid using castor based oils with it in cold weather, or just avoid the cold weather as we’re all vet guys anyway!
Pit Row
2025 yz450f and was using T4 and now T4+ mixed 50/50 with 90 ethanol free
- the past 3 rides I have had popping and the bike cutting out
- today the bike cut out and completely died on the downside of a triple
- I ordered a new fuel pump and sent my complaint to VP
Does VP have any actual recall/refund set up for this?
I have a 5gal pail with only about 1/2gal used that I’d love to get refunded if so.
I had an unopened can of T4+ that had the bad batch number. VP replaced it without any hassle. They asked for a receipt and I provided it from my credit card statement.
I haven't been able to find a list of bad batch #s for the T4+, only T4. Where did you find that? I reached out to 3 different vp reps via email and only one responded. That person told me there was no " company withdraw of t4+" .
I've burned about half of my pail of t4+ without any apparent issue so far.
Same here, that’s why I was curious. I burned a very small amount without issue (plus a previous 5 gallons of the +) but drained it after seeing all the fuel pump issues out of an abundance of caution.
Does anybody remember if they issued anything about the original U4 or just released U4.1 without addressing the problems?
If you go to the VP corporate website, there is a "Quality Support Form" which I filled out and included a picture of my can with the batch #.
Do you guys still buy fuel from VP? Sounds risky.
Risky? Maybe for that one type.
These types of things have come up before. VP makes a ridiculous amount of specialty fuel and are considered the standard for a reason. I run VPR in my 2stroke stuff and Q16 in my race car. I have no intention of changing.
They will get it figured out.
To the guys running T4 / T4+, what is your plan? Just keep using it or make a change?
Unfortunately it's about the only option for me that can be picked up. Still researching but if I can find something else like fuel factory or sunoco locally, switching to that. I'd like to run 100ll but the local airports won't sell it unless you have credentials.
Rx96 is what I switched too.
Post a reply to: More VP issues (potential recall)