Gas Tank Questions

[hootmon]

I have a regular question, then a technical question...

1) Do you fill your tank to the bottom of the neck in your tank as Honda Suggests, or do you "eek" fuel in until it is full to the top of the Neck?

       For me I fill it to as close to the top of the Neck as the pump will allow (some pumps are not very Motorcycle friendly - Full on / Full off)

2) I wanted to know other peoples opinion on a thought I had.
    When I fill my tank, once I get above the bottom of the neck, I have to put in small amounts of gas, and then wait for the vent tube to let air out, then put in a little more.
    My thought.. What if I completely drained my tank (fumes too) and then drilled a hole in the neck just to the left of center (the tank is two halves welded together and has a seem in the middle) as close to the top of the neck as possible. This would allow the air to vent much quicker while filling, but I don't believe it would effect the purpose of the vent tube once the cap is applied.
   I have wondered if rust would form where I drilled
   What are the pro's and cons of this idea??

[lragan]

How much extra fuel, really, does one put in the tank by filling it to the top of the neck?  Is it just the few thimblefuls of the neck itself, or do you get another pint or so by doing this?

The essence of the question then "Is it worth the struggle and risk?"

I confess that I sit on the bike while I fill it, and rock it back and forth so it fills to the bottom of the neck fairly quickly. 

It never occurred to me to do this until I saw Devin do it one day...

[hootmon]

I'd say and extra 5-10 miles.. Now if I got 150+ miles to a tank, I probably wouldn't worry about it, but 5-10 miles is 5-10% further per tank.. Your not just filling the neck. Your really filling the entire top of the tank, you just have to wait for the vent to let the air out behind the neck.. Thus my question about drilling the hole, this would speed up the process and stop the stupid rocking business..

[Herman]

I say go for it....and then let the rest of us know what happened 

[ikkymudd #587]

Be careful using an electric drill near an open gas tank.

[ikkymudd #587]

Sorry, I see you already mentioned it would be empty and clean.

[Curtis_Valk]

How full can you go before it goes out the vent tube?

Remember that fuel is underground temperature at about 65 degrees when you pump it and in summer the fuel will start to expand as it heats up.  It will take up more room and has to go somewhere.  I think that is why the neck is designed that way (to facilitate leaving enough air space for expansion).  Wintertime, you're probably not going to cause a problem topping off the tank.

Curtis

[lragan]

How full can you go before it goes out the vent tube?

Remember that fuel is underground temperature at about 65 degrees when you pump it and in summer the fuel will start to expand as it heats up.  It will take up more room and has to go somewhere.  I think that is why the neck is designed that way (to facilitate leaving enough air space for expansion).  Wintertime, you're probably not going to cause a problem topping off the tank.

Curtis

Well, you just have to ride fast enough to use the gas down before it heats up!!  Curtis, you should have no problem with this, from what Dave says...

[hootmon]

How full can you go before it goes out the vent tube?

Remember that fuel is underground temperature at about 65 degrees when you pump it and in summer the fuel will start to expand as it heats up.  It will take up more room and has to go somewhere.  I think that is why the neck is designed that way (to facilitate leaving enough air space for expansion).  Wintertime, you're probably not going to cause a problem topping off the tank.

Curtis - I don't think you can easily fill your tank full enough to make fuel spit out the vent tube. Even with reasonable expansion.

1) I think this is why the vent tube seems to be on the right side of the tank. By this I mean when you put the bike on the kickstand, whatever air there is in the tank will move to the right side of the tank.
2) Usually when you fill the bike, you go somewhere else afterwords. (Using some fuel)
3) I frequently fill my tank up to just below the top of the tank (I know which pumps locally to go to that are "friendly" - My wife, who also rides, and I have a pump rating system we use when we fill up.. I usually fill 1st (since I have the credit card handy) and when I hand her the pump, I let her know... Oh this pump is a 7, or it's a 3, etc).
4) I live in Florida.. I fill my tank frequently within about a mile from my house. I have never once had fuel come out my vent tube while sitting in my garage at 90+ degrees
5) The fuel fill hole is not at the top of the tank. This means no matter how much fuel you put in the tank, there is always some air.

Has Anyone ever had fuel pour out the gas tank fuel vent tube (Note: I did not ask out any tube..IF you have had float issues, fuel can pour out a tube, but it is a carb tube, not a tank vent tube).

[hootmon]

I say go for it....and then let the rest of us know what happened 

I attempt to seek wisdom before gaining experience...!

Proverbs 19:20 msg ... Take good counsel and accept correction - that's the way to live wisely and well.

[TLRam1]

Hoot, I have talked about this subject and my plans to do this on one of my tanks if not both. Charles measured how much room was left in the tank for me. I will be using a Dremel to drill a small pilot hole than move up to a larger hole. Mine will be on the neck on the right side.

[hootmon]

Hoot, I have talked about this subject and my plans to do this on one of my tanks if not both. Charles measured how much room was left in the tank for me. I will be using a Dremel to drill a small pilot hole than move up to a larger hole. Mine will be on the neck on the right side.

Oh sure Terry.. Not even implemented and you're already re-designing! 
Are you doing this for the same reasons I listed?
When are you planning on doing this?
A review of the success/failure when your done... AND of course PICTURES!!!!

Thanx

[TLRam1]

Here are a couple of threads I talked about this, one has Charles measurement in theory  what could be gained. Yes, I would be doing this for the same reasons even on my larger tank. I just haven't gotten around to it yet. You may have eluded to the vent being at the top around the filler neck, IIRC.


http://www.magnaownersoftexas.com/forums/index.php?topic=1626.msg12340#msg12340

http://www.magnaownersoftexas.com/forums/index.php?topic=2173.msg17038#msg17038

[hootmon]

Thanx Terry for the links.. So, lots of discussion, but nobody had done it yet.. Correct?

[TLRam1]

Correct, I don't think anyone else had the desire to do this just myself. I will in due time. When the larger tank came it was not as urgent, also had an issue after fill-up on a couple of cases and these other bikes kept me busy.