New Owners - Stupid Questions Thread

Here's a place for new owners to ask those "stupid" questions. The kind you're embarrassed to ask for fear of being laughed at, or lectured for being such a noob. Questions like: Where's the fusebox? or What does OBC stand for?

Then hopefully some wise BMW sage who, feeling ambivalent or simply bored, cruises by might share said wisdom with grace and style.

Since I seem to be a frequent violator, I'll start this Thread by asking my next stupid question:

"Is something wrong with my fuel range calculator on the display? It never reads higher than about 110 miles, after I refill the tank. It seems to wait until the fuel level falls below a certain level, then it begins a countdown from 100 toward zero. Is that the way all the OBC's work?


HF

See the little arrow next to the mileage est? When on it means greater than. What mileage the instrument shows seems to vary among bikes and even on the same bike at times. It is not accurate because of the shape of the tank, except for the grossest measurement. Mine usually starts in the ^12? range than slowly increases. Once the arrow disappears it is supposedly measuring true mileage estimate. Mine still varies, being pessimistic until it gets down to about 80 miles.

This symbol ">" displayed on the fuel range means greater than.

The crux is that most BMW bikes including the F800 have strange shaped fuel tanks. The fuel level sensor is not in a place to be able to tell just how full the tank is, but simply that there is more then 2.4 us gallons.

So if your tank is fullish, all the computer knows is that there is somewhere between 2.4 and 4.2 us gallons.

As such, the computer assumes worst case (2.4) and displays the ">" symbol to let you know that your range is likely at least X miles, but may be much more.

Once fuel gets down to a level the sensor can read, the ">" symbol will disappear and live computations will commence.

As far as I know, the only thing changed on newer models is that the range does not count to zero but rather changes to display "--" when range is very low. I do not know if software updates will change this functionality on older models.


Note: the OBC estimates range bassed on averages of past performance, current rate of usage, and other factors.

The OBC's estimate of your range is just a guess. The computer has pretty good information of what has happened in the past, but no idea what will occur in the future. Changes in terrain, elevation, wind, fuel energy content, riding style, payload ect are beyond it's capabilities to control for.

Take the range as a potentially helpful estimate at best.

When the low fuel light kicks on, at best, you really need gas soon!

Actually since BMW is not known for sourcing the best fuel level sensors, there is no reliable substitution for an awareness of how many miles ago the tank was filled versus what demands have been placed on the fuel since.

I strongly encourage use of a trip meter :)

Subscribed!

Get your bikes software updated and you wont have that issue with the OBC. It'll give no distance and then after you hit reserve show you miles ridden on reserve.

Here's a dumb question: Is it bad to use heated grips in the rain?

Only if you hate warm hands.

And on that note; what is meant by 'reserve' on this bike?

I don't have the manual infront of me, but IIRC its ~1.1 gallons remaining.

Excellent input....thanks for that info Itsatdm & Wiseman. I had not noticed the Greater Than symbol, and certainly didn't understand the inner workings. Does BMW not know how to measure volume progressively in the tanks they build? Seriously....not being sarcastic. Seems they would use the same mold to make the tanks the same way, and then be able to measure volume (by sensor height incrementally, very accurately. But what do I know?

Regarding Heated Grips in the rain....definitely no problemo! You will not create a short circuit or an dangerous condition by doing so. You're not very likely to be electricuted by the 10 amp draw (just guessing on amperage) under any condition. Well....er...a...unless you put your feet down and become "grounded". Another fine reason to keep your feet on the pegs!

HF

p.s. What does reserve actually mean on this bike? Would that be when the fuel range counter begins decrementing or when the fuel light comes on? So, would that mean 2.4 gal or 1.1 gal or what?

It varies between bikes. I have run mine close to 0 miles a few times and I had .8 gal left. Fuel light usually comes on around 40 miles to empty, so guessing at that point 1.5 gal. Something you are better determining yourself.

Very interesting, Itsatdm. I'll have to pack some fuel and go run her dry to test this. Seems to be an odd configuration of communication. Countdown to zero, but still have 35 - 40 miles of range remaining. I'd think (or hope) the fuel light and the fuel range counter were sync'd together closer than that. Of course, I understand the fuel range is a computation based on running average for mpg. But still, it ought to be dialed in closer than that.

Nevertheless, it is what it is. So, good advice I think....to go find out for myself. There's that "Knowing" issue again.

Now, come on new owners, I know you have some more stupid questions you want to ask. See what great info came out of the last question? I need your help, as I'm too stupid to even think of all the stupid questions. But here's another:

"If I perform my own oil changes, does that violate my warranty?"

Does all service really have to be done by a certified BMW mechanic to maintain warranty rights? Seems they have a loophole (or more likely "loop-out" at every turn). So, I just want to know....for sure. Is there a real policy rule regarding this issue. Because I'm surely not going to take my bike into the shop for basic service maintenance....like re-adjusting chain tension, bleeding hydraulics in the brake lines, etc. Where's the line drawn?

HF

Here in Canada, I believe that owners are permitted to service their vehicles wherever they want and are not limited to the dealer. Of course if the dealer can establish that the service was performed improperly and problems arose directly from that improper service then warranty may not cover the issue.

Does removal of the charcoal canister void any of the warranty?

There is a Federal Statute that gives consumers protection and many/most states have there own consumer protection laws. It is a voluminous law written and probably only understood by lawyers, here is a short version.
http://www.dummies.com/how-to/content/keeping-your-mods-warranty-intact.html

I have done the typical oil and filter changes, but left the first valve check to BMW. Mainly I did so that so there was no question about the warranty back when I was having issues and because the BMW manual had no info on the shim measurements in case I needed one.

I fully documented what I did with photo's, showing mileage, parts and different stages of the service.

Re: adding and removing parts. If BMW can show a direct connection between what mods you have made and the subsequent damage as to a result to a specific componant, they can void that componant from warranty coverage.

I think I have mentioned, BMW has a lot of Lawyers, use your own descretion.

I document my oil/filter changes and other fluids with pix, but have decided to keep paying BMW to do the torque check of all the fasteners (and the rest of the service). I figure if a part failed or fell off I would be 'holding the bag' if I had torqued the fasteners myself.

As Joel explained, the tank is not a perfectly regular shape. If it was, the sensor could span the entire vertical extent of the tank and be very accurate. However, it's full of bumps and protrusions and curves, and the floor is not level. So while the tank volume can be calculated quite precisely, the quantity of fuel within it cannot.

The fuel level sensor only occupies the lower portion of the tank. For simplicity, let's say it can measure the bottom half of the tank. It will thus tell the bike the tank is "full" if you have half a tank, a full tank, 5/8ths of a tank, 9/10ths of a tank, etc. Because it has no idea how much fuel is above its highest reading, it (politely) declines to guess, and thus you'll only see the fuel level begin to dip when you've used that first half of the tank. This is the same on my Wee.

It would, hypothetically, be possible to calculate instant fuel consumption (the OBC already does this), subtract that from the full tank volume, and display a full-tank level gauge. However, to be accurate this would rely on the rider filling the tank to the same level every time and then resetting the fuel gauge manually - and can you imagine the whining if BMW made that a requirement?

I use a hybrid OBC/brain-o-matic distance-to-empty method - assume the tank is 15 litres (giving me a 1-point-something-litre margin for error), and use the OBC's calculated average fuel consumption (which I reset each tankful). If it says, for example, 5.0L/100km, then my range is 300 and I'll start thinking about fuel at 250.

This is less easy for those of you saddled with miles, gallons and cubits, but still do-able

That's nice explanation Raider, I get it. But I'm saying fuel always finds its own horizontal level regardless of tank shapes, bumps, turns, etc. A taller resistor gauge (or whatever they use) could easily have been installed. And the volumes at said intervals could easily have been measured. Most of the time the 'fuel remaining" would be read by the rider, the bike would reasonably be level.

I was just curious, its not worth further discussion as this input has been most helpful. Super thanks to all for the explanations.

Now....about that Charcoal Cannister. I'm glad Soyanarchisto asked that Stupid Question. And, I'd like to expand on it. Can we remove it? Should we remove it? Is it really needed anywhere besides California? If you did remove it, could an "outsider" still ride thru California legally? Will the bike run better without it?

I hate extra crapola attached to my bike which serves no useful purpose to me.

HF

Short answers here, relatively sure no one will dispute this:

Yes, you can remove it. My dealer did it free of charge and the laws prevent denials of warranty just because you removed it. You will still be covered under warranty and you won't have to worry about it snorting water and stalling your engine.

California can't do jack about what you bring to ride there. My state Texas has no emissions laws for motorcycles (except you can't have new 2 strokes on the road ) and we can run whatever we want. If your bike is properly registered and inspected in a state like Texas you can ride it wherever you want to. You may have trouble getting an inspection in California though but who wants to do that?

I have not got an 8 yet but can anyone tell me the parallel length on the fork tube machining that will allow the fork to be bought up through the triples to lower it, I am vertically challenged thus I am curious to find this out, many thanks Andi.

So....is there a proper procedure for said removal of canister? Is there an AIS system that must come out and some blocking plates needed with it, and all that jazz?

Or can it just be snipped off and sprayed with some antiseptic like collecting the Mountain Oysters from those anxious young bulls in our pasture?

HF :dg