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U-4 race gas for yzf 450

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Thanks for your input!! Heck if it doesnt anything I think they should make mens caloan(probably incorrect spelling) out of it. :cry:

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hey Matt, there's loads of good and bad info on here, make your own mind up regarding the use of products. I've found some bloody good stuff from this site, 450 cam, rekluse etc but there are kids (age and mental age) who will lead you down the garden path, maybe based on one bad experience, or maybe non.

The thread for octance is here:

octane thread

Its my dyno, from my bike - I suppose if worried about the high oxegenation then you can diltue the mixture even more.

I've ridden the bike pinned in 5th (not all day! but often (twice per lap of 12 (thus 24 per race)))for a full practice and then 4 races over 1 weekend with no oil change and she runs fine. No pinking, over run, back fire etc. plugs same as always - oil was shot though. The dyno was done after the race series too. Like I say, pinch of salt.

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Unless your bike's motor is built to run on high octane fuel(which stock bikes aren't) it will only hurt your performance unless your bike was running way too lean then it might even it back out because the higher octane creates a richer environment. Octane means resistance to burn. the more compression your bike makes the more it needs the resistance to combat detonatoin. Stock bikes are not built for that much resistance. Heck if you look at what the road race guys run they run 85-89 octane in their bikes. U4 is 92 octane. Higher octane in a stock motor will not help you.

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you do not have to rejet for it (I do not care what anyone else says about this)

Maybe YOU didn't have to re-jet but others (including myself) needed to re-jet to get the most out of the fuel. Just saying that "you do not have to rejet for it" is not right for everyone. :cry:

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Gonzo, where are you buying U4 at? I've been wanting to try it but haven't figured out where to buy some. :cry:

Metro Powersports has it. Also Brad Lowe carries at his shop in Durrand. The guy from Moto one that always is at Log Road and Red Bud usually has it too.

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you do not have to rejet for it (I do not care what anyone else says about this)

Maybe YOU didn't have to re-jet but others (including myself) needed to re-jet to get the most out of the fuel. Just saying that "you do not have to rejet for it" is not right for everyone. :cry:

no problem jet away - mine ran perfect without rejeting & it runs even better with the JD jet kit....

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Ga426owner - do you know about octane boosters? I started a thread couple of days ago when we got our dyno runs back, Fast Foward increased BHP by 10-12 at least. Usuall short sighthed remarks about fudging and lying etc, but its genuine. Need someone who knows about this stuff to either back it up, or come up with a soultion to prove otherwise.

I have not tried on the 450 - remember octane is not the issue to performance on a stock 450 4stroke -in fact higher octane has caused higher amounts of breakage on these bikes - I would stay away from it. :cry:

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DONT USE THAT CRAP!!!! STICK WITH REGULAR PUMP GAS! The only decent race gas that I have used is klotz.

How about you back up your opinion with some facts? I have used it and noticed that my bike ran a lot crisper and really ripped. Not to mention it smells great IMO. Go buy yourself 5 gallons and try it out on your own. Make sure you store it in the metal container though, because it will lose its oxygenates if you don't.

I bought 10 gallons from Temecula motorsports. My bike hated it! It gummed up my carb. Did not have the crispness like klotz. It goes bad extremely fast (even they tell you it's only good for a couple days). It also seemed like I lost some power with it compared to the Klotz. Blew some more smoke and made my house stink for 6 months.

Here is the Klotz website, check it out! Klotz

ok I can take some bad info on this board, but this is @!$##@$#@!$ ridiculous..To say VP U4 is bad is like saying I can beat RC! I have been using U-4 since it came out in my 450 and although it is expensive it will make your bike run better than it ever can on any pump gas. It adds approx 2-3 hp, you do not have to rejet for it (I do not care what anyone else says about this) It will gum up your carb if you leave it in your carb for extended time (like all gas)- I drain my tank & carb floatbowl every weekend - takes 1-3 min(big deal). If it is stored in metal can like all gas is supposed to it will last years. I have not used Klotz - and have no intention of trying it.(i do not know who even sells it here) VP knows race gasoline and U4 is the best race gas I have used in my 4 stroke. It will never rob power from your bike unless your bike is set up crappy in the first place.....

my 2cents... :cry:

NO it's not $%@#%$%$^$#, it's the %^$^&&$^#$% truth! I have run both in my bike and the vp is crap in my opinion. Yes I did drain the bowel after every ride. Yes the gas was stored in the metal container and only opened when I needed some. The only way I see it adds more power is because it is highly oxygenated. Race gas is only good for a couple months, even when in a sealed metal container. If you don’t believe me call VP, Klotz, or trick. Whatever you prefer and ask them how long it is good for and they will tell you. Klotz told me one month to a month and a half. But my barrel lasted 1 year. The only one I would try from VP is there normal 112 race gas (not oxygenated). I have not tried it cause the first time I did it made me so mad.

When we go riding Matt I’ll give you some Klotz to try

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The only one I would try from VP is there normal 112 race gas (not oxygenated). I have not tried it cause the first time I did it made me so mad.

Dude, it's just race gas, how did it make you mad? :cry:

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Thanks Buddy, I will take you up on your offer.....but I think ultimately i will stick with pump gas, because that s%*t is expensive......... :cry:

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Dude, I just shouted out my window. Did you hear me? You probably live around the corner from me too. I'm near French Valley Elementary!

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Dude, I just shouted out my window. Did you hear me? You probably live around the corner from me too. I'm near French Valley Elementary!

Boy the world is a small place!

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The only one I would try from VP is there normal 112 race gas (not oxygenated). I have not tried it cause the first time I did it made me so mad.

Dude, it's just race gas, how did it make you mad? :cry:

Cause now I have to do work to fix something that should never have had a problem.

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well just to get the hornets all riled up...

Try mixing toluene in with texaco or amaco premium gas. Mix it at ~25% toluene and the rest gas. It makes more power in both yz250f's. I have been using it in the 450 since I got it, but havent reverted back to straight gas yet. So I dont know what it offers the 450.

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DONT USE THAT CRAP!!!! STICK WITH REGULAR PUMP GAS! The only decent race gas that I have used is klotz.

How about you back up your opinion with some facts? I have used it and noticed that my bike ran a lot crisper and really ripped. Not to mention it smells great IMO. Go buy yourself 5 gallons and try it out on your own. Make sure you store it in the metal container though, because it will lose its oxygenates if you don't.

I bought 10 gallons from Temecula motorsports. My bike hated it! It gummed up my carb. Did not have the crispness like klotz. It goes bad extremely fast (even they tell you it's only good for a couple days). It also seemed like I lost some power with it compared to the Klotz. Blew some more smoke and made my house stink for 6 months.

Here is the Klotz website, check it out! Klotz

ok I can take some bad info on this board, but this is @!$##@$#@!$ ridiculous..To say VP U4 is bad is like saying I can beat RC! I have been using U-4 since it came out in my 450 and although it is expensive it will make your bike run better than it ever can on any pump gas. It adds approx 2-3 hp, you do not have to rejet for it (I do not care what anyone else says about this) It will gum up your carb if you leave it in your carb for extended time (like all gas)- I drain my tank & carb floatbowl every weekend - takes 1-3 min(big deal). If it is stored in metal can like all gas is supposed to it will last years. I have not used Klotz - and have no intention of trying it.(i do not know who even sells it here) VP knows race gasoline and U4 is the best race gas I have used in my 4 stroke. It will never rob power from your bike unless your bike is set up crappy in the first place.....

my 2cents... :cry:

NO it's not $%@#%$%$^$#, it's the %^$^&&$^#$% truth! I have run both in my bike and the vp is crap in my opinion. Yes I did drain the bowel after every ride. Yes the gas was stored in the metal container and only opened when I needed some. The only way I see it adds more power is because it is highly oxygenated. Race gas is only good for a couple months, even when in a sealed metal container. If you don’t believe me call VP, Klotz, or trick. Whatever you prefer and ask them how long it is good for and they will tell you. Klotz told me one month to a month and a half. But my barrel lasted 1 year. The only one I would try from VP is there normal 112 race gas (not oxygenated). I have not tried it cause the first time I did it made me so mad.

When we go riding Matt I’ll give you some Klotz to try

I would be mad as hell also if I tried 112(I assume C12) octane anything in my 450 - IT IS NOT MADE FOR 4STROKES and will cause breakage as well as carb seal/accel pump diaphram issues. I am not sure where you get your info and I am by no means a expert and I am wrong on some things - but VPU4 is great gas for my bike and I will continue to use it (AS you call it "CRAP")for more power, store it for long periods of times (a couple of months) if needed as I have done since it came out - I believe you may want to express your issues and concerns to VP themselves....they would be interested in your personal feedback. :cry:

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