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Switch from Pump to C-12

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Posted by: Txbigguy---------------------

Ok guys I have been reading about the benifits from C-12 fuel and I want to switch over to it. Other then jetting is there anything I should do? Should I wait until I do a topend and then do the switch with the new piston and ring?


Posted by: MX-727---------------------

You shouldn't have to do anything else. I found that I needed to go leaner with C-12 vs. pump.


Posted by: '00kx250spode---------------------

I was able to make the only necessary jetting adjustment with the air screw. I had to turn mine in - making the slow circuit richer. The bike bogged terribly until I did this. After I adjusted the screw, it made a very noticeable difference in throttle response.

But note that having to make the slow circuit richer seems to be an exception to everyone else's experience. Go figure.


Posted by: lawman---------------------

i went 1 step leaner on the main & leaned the needle position by 1 step.


Posted by: Rich Rohrich---------------------

Having to lean the jetting across the board is the most common scenario when switching to C12.


Posted by: Txbigguy---------------------

Hey thanks guys. I am looking at switch to either C-12 or Phillips B-32. Rich which one would you recomend?


Posted by: Rich Rohrich---------------------

For a non-oxyegenated fuel I really like C12.


Posted by: MikeKX250---------------------

C-12 is expensive, try to find Torco 110, much cheaper.


Posted by: Papakeith---------------------

Here are the specs for the two fuels mentioned.
VP C-12
Motor Octane:_____ 108 MON
Specific Gravity: ___.717 @ 60F

RVP: ______________7.3
Oxidation Stability (min.) 1440+
Distillation:
10% evap ________@131.0°F
50% evap ________@194.0°F
90% evap ________@228.0°F
E.P. _____________@233.3°F
Color: ____________Green
Lead: ____________4.23 g/gal
Torco Mach 110
Specific Gravity____.710
Pump Octain_______110
Distillation _________F
10% evaporation____@160°F
90% evaporation____@211°F
color______________purple
leaded ____________yes
end point___________246

Can anyone comment on theses fuels using the data I was able to get to tell me if one is better than another, and more importantly why? I'm trying to make some sense out of the fuels I use. This looks like it may be a good learning experience for me. Maybe someone else too.

Mike, where do you get the Torco fuel locally?


Posted by: MikeKX250---------------------

Keith I get the Torco for $4.75 a gallon at my friends gas station/machine shop in N. Scituate. Karls east coast speed sells the C-12 for something like $6.50. I think the Torco and the C-12 are both better than Cam-2, so I buy the Torco. It`s cheaper and my friend sells it.


Posted by: Papakeith---------------------

thanks Mike.
I grew up in N. Scituate, who's your friend? Bob M?


Posted by: MikeKX250---------------------

Yup, Bob M. he owns the Mobil station. He buys Torco 110, 112,114 and 116 in drums.


Posted by: Papakeith---------------------

Anyone gonna help me out on this one?


Posted by: TechKid---------------------

I think you should go leaner since the race fuel carries more oxy. than pump.


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by TechKid
I think you should go leaner since the race fuel carries more oxy. than pump.


VP C12 contains no additional oxygen.


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by Papakeith
Anyone gonna help me out on this one?


Keith - The temp range between the 10% and 90% point on the Torco fuel is fairly narrow with the 10% point being on the high side. Usually fuels like this can exhibit weird quirks and can leave a hole in the fuel curve on engines that run at high speeds with short intake tracts (YZFs CRFs). But the 10% isn't so high that it's guaranteed to exhibit this behaviour. I'd say this fuel is a try it and see call. All bets are off if the fuel is coming from a bulk storage source like a ground tank or large drum. No telling how close to spec the fuel is in those cases.


Posted by: Durt Cycler---------------------

Watch out I read VP C-12 goes bad,dyno showed the bike lost 1HP after being mixed for only 2 weeks.


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by Durt Cycler
Watch out I read VP C-12 goes bad,dyno showed the bike lost 1HP after being mixed for only 2 weeks.


C12 will last as long as any other leaded race fuel if stored properly.


Posted by: Durt Cycler---------------------

According to the guys at ATV News magazine who did the test on VP C-12, 2 week old VP C-12, VP MR-2 the 2 week old C-12 ran 1HP less on the dyno when compared to the fresh C-12. They also have like 3 pages about fuel octane and compression ratios. This is the April 2002 issue.


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by Durt Cycler
According to the guys at ATV News magazine


WELL if it came from them it must be true. :silly:

Excuse me while I go stand in the corner of the internet and bang my head against the wall.


Posted by: jmics19067---------------------

Quote:
Excuse me while I go stand in the corner of the internet and bang my head against the wall.



Quote:
According to the guys at ATV News magazine who did the test on VP C-12, 2 week old VP C-12, VP MR-2 the 2 week old C-12 ran 1HP less on the dyno when compared to the fresh C-12. They also have like 3 pages about fuel octane and compression ratios. This is the April 2002 issue.


Rich
you can use this to your advantage. Just imagine how bad pump fuel loses horsepower before you even get into your bike? I find this a very strong and <ahem> credible :confused: reason to make sure the fuel you use is fresh.


Posted by: fishhead---------------------

Magazines!!!!!
Just because they buy ink by the barrel doesn't mean they know beans about fuel or anything else for that matter. One week, really! Maybe they stored it in an open container.

Two quotes by Samuel Clemmens come to mind.
1) A lie will go halfway around the world before the truth can put on its shoes.
2) Never fight someone who buys ink by the barrell.

C-12 is an excellent fuel for 2-stroke offroad use. The initial point of the evap curve is low enough to give good throttle response and the end point is high enough to provide some cooling effect. As Rich said the evap curve is nice and smooth with no hitches. This contributes to consistent results.

It's better to have 47 horses in the corral than 48 out on the range.


Posted by: nephron---------------------

lol, fishhead. Anyone who quotes Twain is a friend of mine and of course, correct. Particularly in this instance. I've been using C12 recently, & have enjoyed, for the first time in a while, a relieving decrease in time spent cursing jetting woes or trying to achieve reasonable throttle response.

In reality, I think pump fuel's just gotten so damn bad lately that the gap in performance and consistency has broadened terribly. And I've had no problems with storing the C12. Also, hp is a mute point, since (at least to me) the biggest reason to use something like C12 is to improve throttle response and to obtain consistency in jetting. I really haven't been able to tell any difference in "peak" horsepower c/t pump gas, since I can't use everything I've got already. I could see how a fuel with a nice curve and oxygenates could help the cause with a screaming 125, but me? Nah. I'm just a spode that can't use a 3rd of what I've already got. :silly:


Posted by: Papakeith---------------------

Quote:
Originally posted by Rich Rohrich
The temp range between the 10% and 90% point on the Torco fuel is fairly narrow with the 10% point being on the high side.

Thanks Rich, but what part of the fuel is doing the evaporating? Is that like the MBTE that evaportates so quickly, that it evaporates before it can drip? Or am I completely lost here?
I guess I was looking for an explaination on what the numbers mean. Is there something available in the form of a link or a book at the library that I could read about the good bad and ugly of fuels? Or, if you would rather provide a dissertation right here; that would work too.
As always thanks for any insight that you can provide.


Posted by: fishhead---------------------

I'll take a stab here.

The evap curve is provided to let the tuner know what the physical properties of the fuel are. A fuel with a fairly high initial evap point might be best used in a 4 stroke with higher inlet tract temps as the evaporation provides cooling to the intake tract, valves and piston crown. This property enhances cylinder filling. This is a good thing. As an extreme example fuels with a very high initial evap points are often used in turbo applications because low evap point fuels are less ideal as evaporation produces expansion which interfers with cylinder filling and robs power. Not a good thing. The end point is important because if the fuel in the combustion chamber does not get to the end point of the evap curve prior to combustion then there is unburned fuel wasted in the combustion process. Again, this is not a good thing. So the temerature characteristics are different for different applications. Matching the temp charateristic of the fuel and engine is a good thing. This is one reason there are so many different flavors of fuel out there. Generaly speaking offroad 2 strokes prefer a fuel with a fairly low initial evap point. A fuel with a too high of an initial evap point kills throttle response. This is what usually occurs with octane boosters.

I know very little about this subject so if anyone can further enlighten me on the subject or correct my misunderstandings please feel free to do so.

Gasoline is a homogenous mixture of different molecules, kinda like Jim Beam, The more volatile or lighter fractions evaporate first and so on. If you heat up your Jim Beam the alcohol will evap first then the water and finally the brown goo from the charred oak barrels that give it color and flavor.


Posted by: llk---------------------

Just want you guys to know that I read threads like this and start thinking I whould sell my bike! :D There is no way I am smart enough to operate this thing. Seriously I print post such as fishhead's out and read them back just to try to get a handle on them. Thanks for the ecucation.


Posted by: TooTall---------------------

Hey Rich, would you consider it a risky undertaking to try Torco 110 & pump gas (93) mixed 50/50 in a '98 YZ250? Thanks in advance.

TT


Posted by: Papakeith---------------------

llk- doesn't it just make your head swim sometimes?
fishhead- Thanks for the dissertation
Anyone else want to chime in?
Are there any links available for some good reading?


Posted by: 2strok4fun---------------------

Fishhead, a good explanation as far as I know (that isnt saying much) :D but Know brewing better than fuel, trust me there is no color imparted from charred oak, color depends on the malt selection drying temp, boiling temp (for initial brew, pre still) and distillation temp and pressence of vacuum or pressure during distillation.

sorry for the useless zymurgy info just another hobby that consumes money and time BTW i havent made homebrewed wiskey, but from what i have tasted i will stick to beer :confused:


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by Papakeith
Anyone else want to chime in?
Are there any links available for some good reading?


Keith - Here's a link that goes into some of the details and also has some suggestions on further reading

http://www.dirtrider.net/forums3/sh...?threadid=21160


Posted by: titaniumvalv---------------------

I run c 12 in my yzf and didnt really see the need to change the jeting is this comon or am i just to stupid to see the dif.help me out with this feul i keep checking my plug and dont see anything wrong it always looks good and clean and the right color light brown is this normal.


Posted by: fishhead---------------------

2 4 fun,
You might be right about single malt scotches which are fermented from peat roasted barley such as Craggenmore But in the case of Jim Beam the white dog that goes into the barrel is clear as moonshine and 135 proof. After 2-8 years in the charred white oak barrels it has its distinctive color and flavor imparted by the carmelized layer below the char and since 20% of the alky has evaporated its about 80 proof.

Be sure to jet accordingly!!!!


Posted by: Papakeith---------------------

Thanks for the thread link Rich. That should keep me busy for a bit.


Posted by: 2strok4fun---------------------

Be sure to jet accordingly!!!! true fishhead

improper jetting leads to sleeping in the garage with dogs.

proper jetting leads to naked jacuzzi parties

OK back to the subject of fuel, and this is also slightly brewing related.

I have many cornillius kegs (sp) the soda ball lock type, i can use my pressure regulator and nitrogen to dispense fuel from and keep it locked away from any air. does anyone see any problem with this method of storing and dispensing fuel. These are the 5 gal kegs.

chris


Posted by: RYDMOTO---------------------

May I quote Homer Simpson here? mmmm Beeeeer!


Posted by: dave wright---------------------

Has anyone heard of pro-fuel? A local dealer sells the stuff and I was wondering how it compares with VP C-12. Also, is there any difference between using leaded and unleaded fuels?


Posted by: skipro3---------------------

Can someone tell me where I can get VP C-12 in the Sacramento, California area? I went to their site and clicked on the link that is supposed to identify the closest dealer. It didn't work. My zipcode is 95623. Thanks for the help.


Posted by: Superchief---------------------

when i bought my 03 cr 250 the salesman at the dealership told me all i should run in the thing is race gas. his explaination for this was: the bike is made to run off this type of gas, after all it is a race bike, and will always perform at optimum. while i am located 538 ft above sea level, the bike is a tad on the rich side with the stock jetting (small amout of carbon and yuck at the end of the silencer). waiting to install the pipe and reeds and then i'll worry about jetting. only thing i can say is while the jetting may be a little off, this thing rips from the day i bought it. The throttle response is excellent and the front wheel hates to stay on the ground. while i cant say it would'nt perform this well with less octane i've had no prblems with the c-12. i mix it as recommended with hp-2 oil, c-12 fuel at 32:1 mix ratio. guess you have nothing to lose by giving it a try, what's the worse that can happen, it performs better?


Posted by: MX-727---------------------

skipro, there is a shop out in Rancho Cordova that had C-12 when I was in there last summer. I'm pretty sure it was Rancho Motorcycle Dismantaling: 916-631-7900.

Also seems I saw some at a shop north of Madison on Auburn, Performance Cycle: 916-344-7911

If that doesn't work, contact the west coast VP rep: (909) 674-9167 or e-mail: vppacific@aol.com


Posted by: dadshillnut---------------------

So I should run Jim Beam at 32-1 with c-12.


Posted by: MikeeeP---------------------

So I probably shouldn't be going to the junk yard and using their refurbished fuel out of old cars in the trash heap? Hey they strain the water out of it with a big filter - should be good enough right?

Just kidding.

Rich, I have one for you - oxy fuels in 2-strokes. If someone were going to do that, what type of jetting changes would be needed to compensate for the higher oxygen content? 1-2 mainjets up?

I have a specific reason for asking this, but will hold off on that - just curious what you think might work as a safe starting point.

Nah, I'll tell ya. Someone here locally has (had) a YZF250 and they had some of the new four stroke fuel that is oxygenated - just sold their bike and purchased a KTM125 (2003) but still have a large quantity of their 4 stroke fuel... he wants to run it in the KTM, but I told him he needs to be extremely careful, and suggested he go WAY up on jetting, then slowly come back down till it is running properly - I didn't have any way (and don't) what type of increase might be needed in jet size to compensate for these oxygenated fuels.

MP


Posted by: Rich Rohrich---------------------

MP - If you are talking about going from a good quality race fuel like VP-C12 to an oxygenated race fuel like MR2, then 2 steps richer on the main should be plenty for a safe starting point. Fuels like MR2 tends to vaporize really well so nearly all of the fuel that passes through the jet tends to make it to the combustion chamber in a combustible form.

Here's the hook though. If you are talking about going from pump fuel or one of the aromatic heavy cheapo race fuels to an oxygenated race fuel like MR2, then you may have to go a couple of steps LEANER on the main when using MR2.

Seems backwards right? Here's why. Pump fuels, and some of the cheapo race fuels have components that are so reluctant to vaporize that a LOT of the fuel that passes through the jet tends to make it to the combustion chamber in a NON-combustible form (i.e. liquid droplets). If it won't vaporize before ignition then it won't burn. So you end up having to add a bunch of extra fuel to hit your target air/fuel ratio. This is a MAJOR contributor to the spooge problem people experience with these fuels.

So even though the oxygenated race fuel carries additional oxygen, because it vaporizes more completely it takes less fuel to hit the target A/F ratio.

Hopefully this makes some sense, and will help explain why some guys aren't seeing the gains they should from using these high tech fuels.


Posted by: Rcannon---------------------

Rich, thanks. I hate to start buying race fuel, but our local area messes with the pump fuel during the year. I think for the sake of being consistent I probably should.


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by Rcannon
our local area messes with the pump fuel during the year.


Unfortunately they do that everywhere.


Posted by: MikeKX250---------------------

Rich would you consider Torco 110 one of the cheapo fuels that dosen`t vaporize well, or would you call it one of the better race fuels?


Posted by: Rich Rohrich---------------------

Mike - I have no personal experience with the Torco products.


Posted by: andym---------------------

Here's my race gas question. I have access to Citgo 110, Sunoco 110, and 66 110. Which would be the best to use? If it makes a difference, Citgo comes from a barrell and the others come out of pumps and are stored in the ground. The Sunoco comes from the local circle track, the 66 from a gas station, and the Citgo from Napa (they sale alot of it).


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by andym
I have access to Citgo 110, Sunoco 110, and 66 110. Which would be the best to use?


Phillips 66 doesn't really have a 110 octane fuel but they do have a 110 RON fuel called TT105 (formerly B42) . This fuel is designed for lower rpm fuel injected auto engines with long intake runners. Wrong fuel for your application plus anything that comes from a ground tank is a total crap shoot anyway so that's out.

Sunoco 110 is a good fuel but it's probably overkill plus it comes from a ground tank, so you are on your own. Personally I wouldn't waste my money on it unless you are trying to do nothing more than fight a detonation problem.

I have no personal experience with Citgo 110. The specs look basically right, again it's probably overkill. Bulk tank storage is iffy at best, so you might want to take a look at how he is storing it.


Posted by: andym---------------------

Thanks for your input. FWIW, I'm running it in a 02 CRF450 with a EG ported head, Wiseco piston, and a PC slip-on. The Citgo is stored in metal barrels but outside under a carport. He does sell lots of it. I have bought gas from him one weekend and he will have 5 barrels there, go back next weekend and he's out.


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by andym
The Citgo is stored in metal barrels but outside under a carport.



Good luck

FWIW, there are MUCH better fuels for the CRF. If you are going to spend the money for good fuel it's worth the trouble to find one that will provide a noticeable advantage. :thumb:


Posted by: MikeeeP---------------------

Quote:
Originally posted by Rich Rohrich
Here's the hook though. If you are talking about going from pump fuel or one of the aromatic heavy cheapo race fuels to an oxygenated race fuel like MR2, then you may have to go a couple of steps LEANER on the main when using MR2.


Rich box stock 03 KTM125SX... he has VP Ultimate 4 that he wants to run. Being oxygenated I didn't know what to tell him but to be safe and go up and work down.

MR fuels have an oxgen level of about 2.6%, this stuff is supposed to be 6% and really was designed specifically for thumpers... I believe the octane rating is about 98. I don't have any vapor info on it though.

Interesting dilema eh...
MP

BTW, I see Supermotard is getting huge. You've been out there for a long time with that. Did you see the latest results? Jeff Ward and Jeremy McGrath battle it out beating Mike Metzger and one of those famous road race guys was wayyyyyy back in 10th. LOL


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by MikeeeP
Rich box stock 03 KTM125SX... he has VP Ultimate 4 that he wants to run. Being oxygenated I didn't know what to tell him but to be safe and go up and work down.


More often than not you'll find that's the most workable plan.

Quote:
Originally posted by MikeeeP
Did you see the latest results? Jeff Ward and Jeremy McGrath battle it out beating Mike Metzger and one of those famous road race guys was wayyyyyy back in 10th. LOL


After seeing Magoo & Steve Wise flat out spank the big names of their day I'd NEVER bet against a good motocrosser when they line up at a SuperMoto race. :thumb:


Posted by: 2000SE---------------------

I have a 1997 CR250 with a fairly new top end, FMF Gnarly pipe, bosyeen power block and reeds. I have have been running pump gas with 32:1 mix of HP2 oil. I have been getting a lot of slooge at the junction of the pipe and the siliencer. My power is pretty good not too dissapointed with it..good throttle response and all but I was wondering if

A) I should switch to something MR2 or VP. ( I dont race or anything ) so i could lean my bike out to not get that slooge stuff

B) Not switch and just say screw it and try to keep it clean

C) If I do switch how should I re-jet my carb so I dont blow it up?

D) Is it even worth it? Do I run a big chance of siezing my engine...??


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by 2000SE
B) Not switch and just say screw it and try to keep it clean



Learn to jet your bike first then worry about buying trick fuel for it.

http://www.ericgorr.com/techarticles/carbtuning.html


Posted by: FOX426---------------------

Rich, whats your take on Union 76 110 leaded race fuel? It's about all I can readily find around here. I have been mixing it about 2gal. (110) to 1 gal 93 pump gas. On my stock 426 it has given some snap right of the bottom and cleared up the backfire pop, starting has improved. I think these are pretty good improvements; although it is nothing exciting like horsepower gain it has cleared up some annoying charistics on the bike. BTW I am at sea level. What do you think about this combo? Will a steady diet of this hurt anything?Will running straight 110 do anything better? ( Have NOT changed jetting) It always was a little lean from the dealer. Thanks


Posted by: Rich Rohrich---------------------

Union 76 110 is a poor choice for the 426.
It runs richer than most pump fuel which explains the postive effects you saw. You would have gotten the same effects from a jetting change without the expense.

My advice would be to adjust the fuel screw and save your money.


Posted by: bedell99---------------------

Andym & Rich,

Phillips 66 has a 111 fuel now labeled as TT111. It is actually 110.5 octane. I have been using it in my bike with "ok" results. They banned B35(TT101) here in Colorado because it contained MTBE and I had to find an alternative. The TT111 is the only fuel available here that has is somewhat good for an off road application. The TT111(no oxy, leaded) has an alright evap. curve but is in no way comparable to the B35 for an off road application. The B35 gas in my opinion(Price, availibilty, specs., oxy) was the best fuel a person can put in a dirtbike. The TT111 has a nice low 10% boiling point(142f), but high boiling point(300F). The specifications for phillips fuel are located here.

www.p66race.com

Erik


Posted by: Rich Rohrich---------------------

T111 is just Phillips B32 renamed. It's a good fuel, with characteristics very similar to VP C12. It's a really nice easy to tune all around fuel.

Unfortunately the specs Phillips has on the website aren't real accurate (they have the bad habit of rounding a lot of things on those charts) .

Here are the real numbers on the fuel:


RON...............115.6
MON...............108.0
(R+M/2)..........111.8
Lead (g/gal)......4.23
Oxygen (%LV).......0
Specific Gravity.........0.7219
Stoichiometric Ratio.....14.88
RVP.............................6.90
Distillation (deg F)
0.01............108.2
0.05............141.2
0.10............154.2
0.20............174.5
0.30............192.7
0.40............204.8
0.50............210.4
0.90............223.0
0.95............230.5
0.99............266.8


Posted by: Lobster---------------------

OK, my understanding for jetting with oxy fuels is to go leaner. Now confusion sets in. The VP fella that emailed me back said go one size richer. The guy who runs the dyno says he didn't make any jet changes on his DRZ when going from pump gas(practice) to MR2 (Qualify/race) . Rich says go leaner and explains why. I plan on practicing with pump gas and switching to Ultimate 4 for qaul/race.

Rich, I'm gonna be dynoing next week with a new cam and running both pump gas and Ultimate 4 back to back. Does running oxy fuel throw off the gas analyzer at all?


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by Lobster
OK, my understanding for jetting with oxy fuels is to go leaner.


Rule of thumb is to go RICHER when switching to an oxygenated fuel. It's just not a hard and fast rule for the reasons I noted previously. When in doubt start by going richer especially if you are going to be playing on the dyno.

What type of gas analyzer are you referring to? Wideband 02 sensor or 3 gas tail pipe sniffer?


Posted by: Lobster---------------------

3 gas tail pipe.


Posted by: Rich Rohrich---------------------

Those things really respond too slowly to be useful for anything other than checking CO at idle, and ball parking the main. When the mixture is chemically correct the readings will be similar, when the jetting is off the oxy fuel will only make the readings more confusing.


Posted by: *william*---------------------

Quote:
Originally posted by fishhead

If you heat up your Jim Beam the alcohol will evap first then the water and finally the brown goo from the charred oak barrels that give it color and flavor.


How much more HP will I get if I run Jim Beam instead of C-12? Will the brown goo clog my power valves?


Posted by: *william*---------------------

Okay, seriously.

A few races ago (Hare & Hound) I came into the pits and the guys dumped my pre-mixed C-12 into the tank and I took off for the second loop. This was from the same can I had filled the bike up with before the race. After I was out of the pits and got on it, I noticed a big lag from 0-1/3 throttle. It was so noticable I thought maybe they had filled my bike with someone's else's fuel. This continued for maybe 3-5 miles and then throttle response was back to "lightswitch."

What could account for this? I was guessing maybe the can was in the shade, and my bikes tank was black, and that all of a sudden cooler fuel was introduced and was not atomizing/vaporizing as well as the fuel that had been sloshing around in a black tank in the dez for 40 miles. I still have no idea...

???


Posted by: paper racer---------------------

I am running Agip semisynthetic 2T oil 40:1 with 91 octane pump gas but my manual says I should use 95 or higher octane. Should I mix racing fuel with pump gas to bring up the octane to 95. Thanks


Posted by: paper racer---------------------

Sorry, I have a 91 YZ 250. New piston .40 over.


Posted by: Rich Rohrich---------------------

The 95 octane your manual is referring to is RON octane. 91 pump octane that has the (R+M) / 2 sticker on the pump is at least 95 RON .


Posted by: *william*---------------------

No ideas?

On the flip side, Sunday I did a 2 loop dez scrambles, but noticed no difference after the fuel dump in the pits. It was about 20 degrees warmer this last race.


Posted by: motometal---------------------

Rich, you made a general comment on Sunoco 110 earlier...well, this happens to be one of the very few race fuels readily available for us here.

Unfortunately, i'm not sure how good it is for my application (250 2 stroke). Here are the specs:
ron-115
mon-105-oops, I had 110 listed the first time I posted
rvp-8
initial-90
10%-160
50%-220
90%-260
final-360

based on the little bit I have learned so far reading on DRN, my hunch is that the 10% is in the ballpark but the 90% and final are pretty high. This fuel seems to work pretty well, but then again I don't have much to compare it to. The only other source of race fuel here is B32 from the ground.


Posted by: Rich Rohrich---------------------

MM - What is it that you are looking to gain with the race fuel?
Are you going to run it straight or cut? What type of riding are you doing?


Posted by: motometal---------------------

Probably cut 50/50 with Amoco 92, or I may eventually talk myself into burning it straight. My primary goal is a bit of protection in case I get the jetting on the lean side. Behind that, also throttle response, consistent jetting results (yes I know the pump fuel mixture hurts me in this area). Reduction of spooge is always nice as well.

This fuel comes in plastic 55 gal drums and it's fresh weekly. We may be losing a bit of the light ends during the warm summer months, but the only other option here is B32 from an underground tank, or avgas. I play ride mx tracks and woods.

And yes, I am the same guy who has been known to burn 3 to 4 month old pump fuel. But, reading up on fuel here on DRN has increased my interest in this area, I would like to see how good I can get the bike to run with "fresh, proper" race fuel. Not sure if this Sunoco 110 is "the stuff".

Getting a new bike always tends to increase the enthusiasm in several areas as well.


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by motometal
Probably cut 50/50 with Amoco 92, or I may eventually talk myself into burning it straight. My primary goal is a bit of protection in case I get the jetting on the lean side.


You'll definitely get that. The high end point and 90% temps will help cool the piston crown and the lead content/MON bump will also increase your safe margin of error. Assuming of course that the lead doesn't have some antagonistic reaction with the pump fuel components. (it happens )

Quote:
Originally posted by motometal

Behind that, also throttle response, consistent jetting results (yes I know the pump fuel mixture hurts me in this area).


I wouldn't hold my breath waiting for this to happen.

Quote:
Originally posted by motometal

Reduction of spooge is always nice as well.


Good luck. Those same distillation temp characteristics that give you some margin of error in terms of jetting will work against you in this area. It may prove to be better than straight pump premium but you won't know until you test it.

IMO, this is not the "stuff".


Posted by: motometal---------------------

thanks for the reply, Rich. I guess i'm not surprised if Sunoco 110 isn't exactly ideal for my application, considering this type apparently works very well in a stock car (very different application).

This possible reaction with the lead...would the result be potentially damaging or are you just referring to losing some or all of the benefit of the lead?

As I learn more about different fuels, I become increasingly annoyed that 99.9% of the population looks at "race fuel" as a commodity, as if there's only one type and all race fuels exhibit the same properties and characteristics. Sort of like comparing "steel" to "aluminum".


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by motometal
This possible reaction with the lead...would the result be potentially damaging or are you just referring to losing some or all of the benefit of the lead?


Nothing dangerous, just losing the postive aspects.

Quote:
Originally posted by motometal

As I learn more about different fuels, I become increasingly annoyed that 99.9% of the population looks at "race fuel" as a commodity, as if there's only one type and all race fuels exhibit the same properties and characteristics. Sort of like comparing "steel" to "aluminum".


You're preaching to the choir brother.


Posted by: biglou---------------------

I've read this thread several times, but there are a couple new pages added since my last visit. Wish I would have read it one more time last night. Might have saved me some grief! Mistake #1: Read it enough to see that there might be more useable fuel when switching to race, and let that influence my jetting in making the switch to B35. That put me way lean on jetting. Mistake #2: Stopped visiting this thread after confirming in my walnut-sized brain that C12 was non-oxygenated fuel. "Nothing more to learn in this thread that could possibly benefit me, right?" :silly:

I amaze myself sometimes... :confused:


Posted by: motometal---------------------

Any rough idea what the distillation curve would be for Amoco ultimate? I realize this could vary seasonally, etc., did a google search and didn't come up with anything. Just trying to get some basic numbers or a range for comparison's sake.


Posted by: MikeKX250---------------------

I haven`t heard anyone mention VP Red yet. The VP Red is a leaded fuel with 105 octane.


Posted by: Rich Rohrich---------------------

That's becuase VP Red is is a poor choice for most motorcycle applications. Of course that doesn't stop people from using it and complaining that race gas doesn't do anything.


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by motometal
Any rough idea what the distillation curve would be for Amoco ultimate


Dr. Dave Redszus the blender of FirePower race fuels gave me these numbers as typical values at the refinery for Northern Illinois in the summer.
10% - 158.0
50% - 250.0
90% - 374.0
End point - 437.0

The EPA can provide the seasonal temp ranges for your area, but there are a couple of key points to remember. The EPA seasonal values only have to be met at the refinery not the pump. The 50% distillation temperature in Illinois (summer) has an acceptable range of 170-250F . Think about that. A single point on the curve can vary by a larger range than most race fuels change from 10-90%, and that is at the refinery point. By the time it gets to your engine the range is even greater. I have a fuel quality study done by American Automobile Manufacturers Association from a few years back. They did tests at the pump at a wide range of locations. I'll try to dig it up , but the basic point was what comes out of the pump is vastly different from the "numbers" the EPA quotes. The relative quality of pump fuel is really bad.

Considering all of that it's no surprise that pump fuel is a poor choice if performance and good response is your objective.


Posted by: motometal---------------------

wow, that's a high end point! I would think if I tried running fuel like that in the winter time, even more of it would just shoot out the pipe as spooge, and the bike would run even leaner than expected (especially on a liquid cooled bike with no thermostat). If this theory is correct, many snowmobiles could be jetted much leaner if run on proper fuel, but then again that would get a bit expensive feeding three big Mikunis instead of one.

I wonder if 20 or 30 years ago pump fuel varied this much? Or are these folks taking advantage of the fact that most modern vehicles have oxygen sensors and automatically adjust (within limits) for differences in fuels?


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by motometal
If this theory is correct, many snowmobiles could be jetted much leaner if run on proper fuel


That tends to be true for ANY engine all year long. The higher an engine revs the more significant the influence of proper distillation curve will be. It takes time for fuel to vaporize and there is less of it available as the rev limits of new engines increase. Nothing of late is funnier to me then a guy who can't jet his way out of an empty field who drops $400-$800 on an exhaust system, ignition and intake plate hoob-a-joo for his 250F then pours pump gas in it and proceeds to bounce it off the rev limiter. No wonder these guys wear out main bearings and rods so fast, half their fuel is still liquid in the combustion chamber and running down into the crankcase dilluting the oil. :silly: All the idiotic my oil is better than yours posturing is pretty moot when 5% of your crankcase is filled with raw fuel. :silly:


The months of spring where pump fuel is being transitioned from a winter blend to a summer blend can make jetting really erratic because the blend from the same company can change pretty dramatically between fill ups. When guys argue that their bikes are jetted SPOT ON with pump fuel and still bitch about endless "performance" maladies I stop listening. There is only so much ignorance driven smoke that can be blown up my butt before it gets hard to sit down.


Posted by: MikeS---------------------

Quote:
Originally posted by Rich Rohrich


No wonder these guys wear out main bearings and rods so fast, half their fuel is still liquid in the combustion chamber and running down into the crankcase dilluting the oil. :silly: All the idiotic my oil is better than yours posturing is pretty moot when 5% of your crankcase is filled with raw fuel. :silly:


There is only so much ignorance driven smoke that can be blown up my butt before it gets hard to sit down.


OUCH

Just seen it happen this weeked to juniors friend...bike was set up perfectly on fresh C12. The dad decided to run AV gas because he gets it cheap. He said he was told it is just as good if not better. Well a dnf at a national race when you are leading the series stinks..... Talk about a sore butt.

&nbsp;

Early in this thread someone mentioned VP Ultimate 4.&nbsp;A friend put it in his DRZ and said it worked fine .. no jetting changes at this point. We tried it in Juniors RM85 (100eg.kit) Junior keeps it pinned&nbsp;alot. We noticed some detonation at hi RPM.&nbsp;I did run it with 1&nbsp;&amp; 2 size over main jets. MR2 seems better. I sometimes add 5-10% VP red to&nbsp;these fuels to raise the End Point to cool things down.&nbsp;

&nbsp;


Posted by: shifting---------------------

I want to run race fuel in my CRF. I Just bought 5 gallons of sunoco 110 . OOPS! I didn't really notice any difference. Is the VP ultimate 4 what I want to use? Any ideas on price? We're up here in Gods country at about 4800ft. Jetting gets to be game around here. One day 65 degrees and 90% humidity and the next it's 85 degrees and 10% humidity! The last thing we need is irregular consistency in our gas.

Rich, have you wrote a book yet? on everything!


Posted by: MikeS---------------------

Ultimate 4 is heavily oxygenated. It should run leaner than most other fuels.

Try it but I have no experience that high up...


Posted by: motometal---------------------

Rich's response on Sunoco 110 was in reference to my application, which is a two stroke. I suspect this fuel would work a bit better in a "big" four stroke, more time to vaporize? No doubt still not the idea fuel though.


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by motometal
Rich's response on Sunoco 110 was in reference to my application, which is a two stroke. I suspect this fuel would work a bit better in a "big" four stroke, more time to vaporize? No doubt still not the idea fuel though.


IMO, it's not a particularly good choice for CRFs or YZFs either. They have very short intake tracts, run much higher rpm than say a CR250, and transition through the rpm range much too quickly for a fuel like this.

It would be an OK choice in a low rpm, slow revving engine like an XR600.

I haven't run Ultimate 4 so I can't comment other than to remind everyone that VP is a marketing company, so it might be best not to have blind faith in all of their advertsing claims.


Posted by: shifting---------------------

I understand that any company that has somehting to sell will tell you what you want to hear just so you buy it. I just don't have the knowledge yet of what to look for on race gas. I've had to read this thread twice. MY BRAIN HURTS!!! If anyone has had good luck with any fuel on a CRF, please comment. Rich, strait up, what would you run in a CRF?




Posted by: Rich Rohrich---------------------

I generally run Phillips B35 (now called TT101) in warm weather and run Phillips B32 when it's cooler out. I jet for the B35 so as it gets colder the change in air density will pretty much balance with the richer running of B32.

Dr. Dave Redszus who did a lot of fuel blending work for Phillips is getting ready to announce his own custom fuel blends under the FirePower brand name, and I'll be switching over to FirePower as soon as Dr. Dave has it all up and running. Before the end month I'll have a complete write up on the FirePower fuels and the unique numbering/naming system they will be using that will pinpoint the fuel's specific characteristics. It will correspond very nicely with the things we have been discussing here.

Stay Tuned.


Posted by: shifting---------------------

Plead stupidity and someone always feels bad for you! Thanks Rich.


Posted by: Txbigguy---------------------

Rich,
Does Phillips have a website. I want to run this fuel but cant seem to find anyone around that carries it. I am here in Dallas. If you could point me to a website so I can contact someone and find out where to get it I would be very gratefull.


Posted by: Rich Rohrich---------------------

Here you go TX http://www.cpchem.com/fuels/contact...tors.asp#United


Posted by: Txbigguy---------------------

You da man......


Posted by: biglou---------------------

Rich-Is B35 any harder (or is it perceived to be harder) to jet for than B32? Just wondering why the local price is about a dollar a gallon more for the B32. My first inclination is that people don't want to take the time to fool with the oxygenated stuff, and buy more of the B32, therefore the shop charges more. Keep in mind, I hate this shop, but they are close. To date, one can of race fuel is the only thing I have ever bought from them in this lifetime.


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by BigLou
Rich-Is B35 any harder (or is it perceived to be harder) to jet for than B32? Just wondering why the local price is about a dollar a gallon more for the B32


I haven't found B35 to be any harder to jet. The main oxygenate (15% by volume) in B35 goes for about $10/liter on the street in small quantities, which I believe is a big part of the price difference. Even at the wholesale level it isn't cheap.


Posted by: bedell99---------------------

Rich before they ripped out B35 out of colorado, it was going for $3.00/ gallon while B32 is going for $4.10/gallon. You would think the B35 would be more?

Erik


Posted by: JTT---------------------

Quote:
Originally posted by Rich Rohrich
It would be an OK choice in a low rpm, slow revving engine like an XR600.


Is this because of the relatively high 10% point?

Sunoco 110
initial-90
10%-160
50%-220
90%-260
final-360

I'm trying real hard to get my poor little brain around this fuel thing, but struggling


Posted by: jmics19067---------------------

Or the really high final point?


Posted by: Rich Rohrich---------------------

The 10% temp isn't really too bad, it's the other points on the curve that are significant. Because the temps are comparatively high, you need more heat or more time to vaporize the fuel. The XR600 revs slow and peaks at a fairly low rpm (time), and the air cooling ensures there will be plenty of heat available in the intake tract to vaporize the fuel. In addition the high end point temp can help cool the piston crown and help stave of knock a bit longer. This is a real issue on XRs that are run hard for long stretches. The downside? Too high a percentage of aromatic hydrocarbons with heavy ends makes for sluggish throttle response. Cutting VP Red with small percentage (20-50%) of a good low temp oxygenated fuel can give you a better throttle response while still retaining some of the positive aspects of the high temps for a better overall fuel in this type of application.


Posted by: JTT---------------------

So, I am guessing that for, say a 125 (high reving, relatively low temps, and short intake) that you would be looking for a fuel with a fairly low 10% point (say 125-135) for throttle response, with slight "kick tail" on the curve nearer the end point (for the cooling effect)?


Posted by: Rich Rohrich---------------------

Yep, that's pretty much the case. Engines that don't get pushed at WOT for extended periods tend NOT to need the tail at the end of the curve. B35 is a pretty good general purpose curve to use for comparison purposes.


Posted by: JTT---------------------

Ahhh...it's coming clearer....ok, so I think I understand the tail end some now. What about the low end of the scale? I would think you would want low numbers in the 10% portion of the curve for throttle response right? If that is true, why would you not want even lower 10% points....think I just answered my own question...too low 10% point and the fuel will become vapour before it gets to the combustion chamber, right?

So the shorter the intake tract and the less heat you are dealing with, the lower you could go with that 10% point?...in theory.

...and the 50% point kind of gives you an idea of the general shape of the curve, therefore the characteristics (whether there are large amounts of heavy ends or just a kicker), right?...maybe?


Posted by: Rich Rohrich---------------------

It's always a matter of balance.

B35 strikes a good balance as does C12 , but it's always possible to tailor a fuel to a specific application if you are willing to think hard about the problem areas and do some testing


Posted by: JTT---------------------

Thanks Rich!! You truely are THE MAN! :thumb:


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by JTT
Thanks Rich!! You truely are THE MAN! :thumb:


NAH, I've just had the advantage of 30 years of trying things out and asking scary smart guys a trillion stupid questions they were wiling to answer (when they stopped laughing at me :thumb: )


Posted by: JTT---------------------

Quote:
Originally posted by Rich Rohrich
asking scary smart guys a trillion stupid questions they were wiling to answer (when they stopped laughing at me :thumb: )


Humm...seems I just experienced that myself Thanks again!!


Posted by: Rich Rohrich---------------------

Quote:
Originally posted by JTT
Thanks again!!


My pleasure. :thumb:


Posted by: biglou---------------------

This thread goes into the archive when it runs its course. :thumb:


Posted by: Senior KX Rider---------------------

Lot of good info in here :thumb:


Posted by: shifting---------------------

Rich Rohrich, has a picture of Einstein as his avatar, yet so humble.



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