Wasted Fuel - Right Side of V11 Sport/LeMans Tank

[al_roethlisberger]

Allright.....assuming the mechanics were partaking of a little hooch or blow, or whatever and disregarding the 'tempest in a tea pot' story. Why not just ask MG what the heck they had in mind with their fuel tanks? I do know that fuel systems are touchy...electric fuel pumps..both external and submerged are expensive and I think that they do operate differently. I myself would be more worried about fuel starvation than extracting every last drop from the tank. Was it an oversight by the Guzzi design team to leave fuel trapped in the tank? Beats me...why not askTHEM.

I do know from personal experience that starving the internal electric fuel pumps of gas means no cooling or lubrication and leads to a shorter life and possible engine damage due to low fuel flow. It would be nice to know the answer(s), but as long as the machine runs as intended it seems they knew what they were doing. As for me, when I see the little yellow light, I'm going to start looking for a gas station...I'd rather be riding    than wrenching

 

These are all good questions, but(again not to sound persnickety )... why don't you go ask Guzzi and let us know when they get back to you?

 

Just pickin' at cha

 

 

But seriously, Guzzi is about the most un-forthcoming about their engineering, standards(They change oil recommendations whenever one seems to ask ), or designs <_ heck they changed the location for electric fuel pump at least times from through in some cases using two of locations randomly throughout a single model year src="%7B___base_url___%7D/uploads/emoticons/default_unsure.png" alt=":unsure:"> This is why Evoluzione gave up on their cold-air induction kit <_>

 

I wouldn't hold your breath for anyone from Guzzi, or especially MGNA, to get back with a straight answer... unfortunately. Other than a few good dealers such as TLM, Moto International, MPH... there are few that either know the answers, or are willing to wade through MGNA's or MG Corp's red-tape and waffling, and I can't blame them.

 

We've asked/complained many times on this forum if anyone from Guzzi ever checks in.... we wish they did. But hey, maybe it's people like us that inspired them for the new tank design

 

 

But back on topic .... I think I can answer your question about fuel-starvation and pump cooling/durability. You are correct that electric pumps of this type use the fluid to cool them, and potentially lubricate their mechanisms. But in this case, assuming MG took this into account for their tank design, it would be a valid point if the system was designed in such a way that the consumption of the fuel supply was cut off at some point to guarantee that fuel was still available to keep the pump lubricated/cooled. And to your point, I agree that it is no doubt "better" not to run the pump dry too often.

 

But the very problem we describe indicates that in practice, the 2002 and earlier design operates in complete contrast to this... letting the engine potentially completely run out of gas(ergo starving the pump of fuel/coolant as you describe), but still have perfectly good fuel sitting unavailable on the other side of the tank That can't be "by design". Instead, I think they just didn't care about that extra gallon.

 

 

Look, I'm sorry... I'm perfectly happy to attribute many great engineering qualities to MG products, and is why I own one But lately, Guzzi has been breaking a whole lot of things that didn't need fixing:

 

1) Fuzzy paint bubbling off

2) Hydraulic lifters/cams grenading

3) Single plate cruiser clutches frying

 

... etc

 

And is why according to rumour why Ivano fired the lot of engineers responsible for many of such snafus.

 

Is this particular issue of "wasted fuel" one of those snafus? I don't think so, but I do think the design was a bit short-sighted, perhaps "on purpose". Again, perhaps since the V11 was originally purely a "sport" design, range and fuel economy wasn't a big concern. But with the advent of the LeMans, and other folks trying to tour on the Sports, range and this "wasted fuel" has come up.

 

Again, maybe this, along with the vapor lock issue, is why they finally introduced the in-tank pump as of 2003. I'd like to think so But somehow I doubt it

 

But hey, it looks like you have a 2003, so I don't think any of this is a big issue for you though. I've not heard of any VL on any 2003+ bikes. But we still haven't heard from anyone about net fuel range on the newer bikes, so the question still remains about total range, and how the new bikes handle that "1.5 gallon reserve" the new bikes are shown to have. Maybe this "vortex" theory is correct for those newer tanks I have no idea, and is why I happily wait for someone with a newer tank to describe just how they function, and how well they utilize their available fuel supply

 

Hope that helps

 

al

[belfastguzzi]

... is why we need an outlet or balance tube connecting the two isolated halves... which become isolated once the tank is about 2/3 empty. Regardless of where the fuel dumps, right or left(although right makes it worse to some degree) the end result is...etc, etc, etc

Something positive could yet come out of these posts. I reckon if all the words were just re-ordered a bit, there must be the perfect test question in here for selecting which kids go to grammar school and which ones go to secondary school (sorry, that's a local example that probably doesn't translate to other education systems). It could be called the Vortex Test and Al could get the Nobel prize for services rendered.

 

Ok, the real question is: what's that chin pad (as mentioned by Al) for anyway? Is it decoration, or do Italians have very long chins?

[mik]

Al, I did email Guzzi yesterday and am waiting to see if they respond. As far as mechanics go, the two that work on them where I trade are top notch. I'm sure that they yank my chain when I ask questions they deem pointless. I researched the motorcycle, the dealer, his mechanics and other MG customers before buying my LeMans. They were highly rated and why should I doubt satisfied customers.

I get the feeling the mechanics don't want me messing with the machinery...they set it up (faultlessly), test rode it, and signed off on it. It runs perfectly so far and I was warned about the idiosyncracies of MG before buying. The mechanics make a point of asking about the machine whenever I see them...they will adjust my suspension, check the engine management or look at any niggle on request. I have to get involved a little though...I want to be more than just a passenger. I'm sure the day will come but until then, I don't care if those guys sprout wings, wave a magic wand and tell me they sprinkled pixie dust on my ride...so far so good. If I get a reply from Guzzi, I'll be sure to share it...I'm just as curious about the fuel tank too.

[al_roethlisberger]

....washing machine sprung a leak, so my progress has slowed a bit on this project, but all-in-all it may be a good thing For example, because of delays, I was able to leave the tank full of gas on a rack, sitting in the Sun, for two days.... to see if it would leak. "Knock on wood" but so far... not a drop

 

 

But I was able to get a few things done:

 

- Got the new tap installed under the tank(only possible if one has removed the airbox) including self-sealing quick-release

- cleaned the tank

- reinstalled manual petcocks, fuel level sensor

- installed new heat-reflective barriers on tank(including above cylinders)

- mocked-up fuel-line routing

 

Some photos:

[al_roethlisberger]

A little closer, taking in both petcocks, and the fuel-return. The gold/black fitting is a self-sealing quick-connect

 

Nothing like disconnecting a fitting and having all the fuel dump out!

[al_roethlisberger]

And closer yet ....just in case you missed it in the last two posts

[al_roethlisberger]

Here is a shot of the inlet inside the tank, taken through the neck. All that goop around it is some stuff from Peratex that is supposed to be used to seal stuff like this, and is "resistant to fuel" ...hence my testing for the last few days

 

The place I pierced the tank was the most accessible, and relatively flat enough to get a good seal. In actuality, I don't even think I needed the "goop" so much, because if you ever remove the stock petcock/sensor base, you'll find that they're only sealed via a single o-ring, two bolts, and some similar non-curing "goop"... and my inlet is on much tighter ... again "knocking on wood" Also, the inlet is a very tight fit in the hole I drilled, and actually is threaded into it. So that should help sealing a little bit as well.

 

What you also can't really see is that the inlet is reinforced by some extra wide stainless steel washers to reinforce against and distribute any undue force on the tank material. Hopefully this will prove sufficient over time. I have to say I was pleasantly surprised by the durability/toughness of the tank plastic when I was drilling and wrenching on it. So time will tell I guess... here's hoping

 

And if I can manage to get a wrench in there(wow it's hard, the neck is so narrow), I also plan to put a 90-degree fitting on the inlet inside the tank so that the fuel doesn't shoot up, and run right down the fitting. I don't think it will make a huge difference in durability, but I'd rather not have fuel splashing right down on the location where the fitting is sealed piercing the tank. ...don't want to push my luck, and everything helps

 

 

 

P.S.

You can see on of the white vent/drain tubes inside the tank in the photo.

[al_roethlisberger]

Here is where the other end of the return fitting connects to, the relocated remote pressure regulator.

 

It's made by the same folks that make our stock unit, Weber, and in fact I used the stock cartridge in this body.

 

It's attached to my fabricated undertail fender extender, that adds some protection for the shock, battery, and various wiring.

 

There's a thread with photos somewhere on the forum:

 

Undertail Fender Thread

 

.....but basically if one removes the rear hugger, the stock undertail fairing ends right before the battery, and leaves much exposed to debris and water

 

Anyway, this location allowed a good bit of flexibility for me, and located the regulator away from heat. There wasn't any real room under the seat, and the ontly other useable location would be up in the fairing, but I didn't want to run more fuel lines past "heat central"

[al_roethlisberger]

BTW, I just filled up the 2002 tank after my modifications, from bone-dry.

 

5.69 US Gallons ...so the 5.5 gallons capacity specified from the manufacturer seems accurate, close enough, and represents total capacity of the tank, regardless of "reserve".

 

....and with the modifications detailed in this thread, all of that is now available to the fuel system

 

It will be very interesting to compare this capacity to the 2003 with the in-tank fuel pump when it gets here in a week or three...

 

I'll update the thread as soon as I get a reliable read from the low-fuel sensor if these modifications seem to have added any pre-warning range.

 

al

[al_roethlisberger]

So, a quick update on capacity and any changes to range regarding the fuel warning light...

 

 

Last night my light lit pretty solidly at 110 miles. Since I had done a dyno run, been running the bike "hard" this last week, and did quite a bit of test running in the shop after filling up the tank, this sounds like that even after the dual-tap modification, the fuel reserve light will still come on at about the same time as before... around 120-130 miles.

 

But this isn't really a surprise or disappointing, as the "wasted" fuel level was always below the "empty" level of the fuel sensor anyway

 

After filling up(4.1), I calculated that I actually had ~1.6 gallons left in the tank of "reserve" now with the modification. So that's pretty significant

 

Now, what will be interesting is to watch my fuel consumption, and ultimately the range, now that my dual-plug conversion and ignition remap is complete. I'd really like to hope that range/efficiency will increase a little. Only time will tell though.

 

 

al

[Guest dkgross]

and, of course, a nice lovely closeup of the Ohlins rear shock

 

[al_roethlisberger]

...yeah, I know... those things suck

 

 

[Guest IanJ]

So, Al, can you describe your new system in an "overall" way? I'm unclear on what all you've changed and what problems you've worked to solve. Ideal would be a diagram, but I'm interested in whatever you can elaborate upon.

[Guest dkgross]

I do it old school. When I hit 100 miles on the odo, I LEEEEAAAN the bike WAY over to the left to slosh a little extra out of the reserve into the left side of the tank.

 

 

[al_roethlisberger]

I do it old school. When I hit 100 miles on the odo, I LEEEEAAAN the bike WAY over to the left to slosh a little extra out of the reserve into the left side of the tank.

 

 

Unfortunately is ultimately ineffective ....because which in about 2.6 seconds(OK, that's a SWAG ) the "sloshed fuel" gets pumped right back into the right-hand "saddlebag" as the EFI loop recirculates the fuel past the injectors <_>

 

 

 

Well, it "kinda works" if you keep "sloshing" every few minutes.... I've done it. But it's an odd "reserve" function if you ask me