What kind of gas do you use?

higher octane with PCIII?

just curious if anyone has found they need higher octane after the install of a PCIII, im ready to purchase one and was wondering.

 

Troy; The power commander for the Fifth gen. VFR's does not change the timing,so in theory you shouldnt need to change the grade of fuel that you currently use. by the way my wife and I have a camp in Gouldsboro,Me.Some great areas to ride in that neck of the woods!

 

I'm pretty sure the reason it runs cooler is because it is slower to burn and probably doesn't burn completly. If your bike doesn't spark knock I wouldn't run it. I think I would invest in some header tape or something that would help th issue and not hit you in the pocket every time you fill up. just my $.02

I didn't even notice you are from Maine. glad to see someone from my spot on the map.

 

Does anyone have any thought on advancing the timing along with premium fuel to boost HP?

 

Back in '84 when we were racing the '83 VF750F we were puzzeled when our friend was taping up his radiator because his enginge was not coming up to full operating temp, while we were experiencing overheating problems. Turns out he was running CAM2 while we were buring pump gas. We found that by mixing the two we could lower the temp of the bike. We would custom mix the two to get the correct temp for ambient conditions. CAM2 burned much cooler that regular pump gas.

 

yeah, Maine sure has some scenic rides and it offers the challenge of dodging pot holes and moose! my wife and i dont get up in the Bangor area often, mostly central Maine and to the west, i have had the pleasure of riding the "airline" at a high velocity!!! (route 9 i believe?)............... now i have to go look up Gouldsboro!!!!

 

I like your picture. Do you have anymore?

I have found that leaving the fans on all the time and a new thermostat keeps the temps below the first mark on the bike. I guess I should look into getting a temperature switch.

Any buddy have any other tips or horror stories with the pump gas?

 

A word of caution in mixing fuels. Modern engines run to pretty tight specs for fuel, ignition and exhaust flow. Changing fuel by mixing in different fuels can have a long term damaging effect. You may solve one problem short term but make a much bigger one long term. Just remember there is a reason race engines don't tend to last very long. For the cooling issue I would say the fan switch makes to most sense. It's cheap and you have easy control. Another thought, even though the gen 5's seem to run hot they don't actually seem to have a high unreliability rate so it may only be a perceived issue.

 

Wow, $3.17 per gallon?! I guess that's what we have to look forward to here in Florida. I don't have a preferance of one station over another but, I always here that the higher octane burns cleaner and is better for the engine. I put the super unleaded in when i have the extra bucks to spare.

 

This discussion got me thinking so I did some research (damn engineers). In summary here is what I found.

In general you do not get more power with a higher octane rating than the engine is designed for and may in some cases actually get worse performance. Higher octane fuels burn slower so they may not burn completely. However the difference is so small you probably won't notice it.

BUT. Depending on the mix in the fuel higher energy components may be present and you MAY, with a specific brand, get more power. The reverse is true with fuels containing ethynol as ethynol has lower energy per unit volume than regular fuel.

HOWEVER, if an engine is designed specifically for alcohol based fuel it will run richer and more fuel equals more power.

Everybody confused . It is a very complicated and to be honest beyond me in the fine details.:help:

So as a summary we may all be right but it is very dependent on the specific fuel used and in general running a higher octane gas than the manufacturer designed the engine for will not give more power.

 

I studied Verbrennungskraftmaschinen (combustion engine technology) at a german university for a few semesters, and I run 89 non-ethanol in my 2007. The octane rating as mentioned earlier decides the combustion point, and altering that point causes knocking also as stated, it is an interesting idea to alter the timing to delay/accelerate the prime piston position to achieve the optimum combustion with a certain octane, but I would say if you dont want a big headache, just run suggested fuel and get a PCIII.
what i DONT know is if a PCIII can alter injector timing in some way that might let a higher octane work well. Thats shaky ground methinks.

 

Here in Australia we have three options for unleaded fuel:

Regular unleaded = 91 octane
2 levels of premium unleaded = 95 octane & 98 octane

I find that I get better fuel economy & tank range using premium unleaded. Was also the case when I had the '94.

 

Do they use ethanol in your gas there?

 

Ethanol is used in some fuel. More likely to be in fuel sold by independent retailers. (Supposed to be 10% content, but some have been found to have a much higher concentration.)

The major companies (BP, Shell, Caltex etc) do have ethanol in fuel (fixed at 10%,) but those pumps are clearly marked that there is ethanol in the fuel.

I usually fill up using one of the major retailers & make sure I'm at a pump with no ethanol content.

 

Did anyone answer this really? My rig did that yesterday. 85 VF700.

Ran great until then, after a few moments, started and ran. It feels just like a 1100 Kawi I used to ride. Vapor lock on all days, not just hot.

Does this rig have a fuel pump that might be failing. It is carb'd.

 

I know why mine is doing that now. With a gravity feed it was getting enough gas at times and would starve. When the gas trickled back into the carbs everything was working as it should. With my fuel pump installed there seems to be enough pressure to keep the carbs filled. Now that isn't a long term fix. That seems to be a symptom of the problem. What I think the problem is, there is something in my tank that is clogging the petcock. It could be rust or dirt but it will get down and cover the hole and plug it up. A full cleaning of the tank would fix it. But I haven't gotten to it yet. So if you can you should see if you can clean your tank and then change the filter. If you have a pump it could be really bad. But if you don't it could be a little problem that the pump could help with. Thats what I think it was. But I narrowed it down to the tank so its in there.

 

Thanks. I have not check that, and the tank is full (I'll burn that off this weekend). After that I will remove tank and have a radiator shop clean it. I will check the petcock and filter at that time.

Thanks!

 

The problem I have with fuel here in the US, is that the actual Octane rating is a average rating, & that pump fuel could be down or up on the rating.

I found that if I mix a good race gas thats unleaded like VP MS 103 1 gallon to 4 gallons of pump it tends to stabilize the fuel. & when I'm on the track & or racing (not a full blown race bike but Super-Stock maped & timed) I mix 2 gals of race fuel with 3 gals of pump chevron 91.

All my pre-detonations stopped, & the motors run much cooler, as well as on the tear downs, I'm seeing even less or most often "NO" damge, then when I ran straight 91 pump.

you all might consider that elevation plays in part with what octane level is needed by your bike as well.
usally higher elevation states & or communities have 85 octane for reguler unleaded with mid grade @ 88 with super still being 91.
So if your bike is timed & maped for 87 octane & your 4500 ft or higher in elevation, your going to lose performance & just pissing un-burned gas & money out your exhaust.

 

You only need higher octanes if you have higher combustion ratio's. Usually to prevent detonation. I know cars with 12.0 to 1 pistons that need 92 or higher.

And no, they arent in kia's.... (even with nos stickers)

 

When I had my GPS I tested my computer room and it is 5,276 feet above sea level. That is 4' short of a mile high. I think that my ceiling is exactly a mile high.
There is a thing we use here to fix are cars high altitude mixture. Lower altitudes are richer and do waste gas.