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fuel filler mod?

klkbeemer

New member
Somewhere i read a thread and details on modifying fill neck in gas tank to make it easier to fill but cant find it and have done searches. Can anyone help ?

Thanks
 
Somewhere i read a thread and details on modifying fill neck in gas tank to make it easier to fill but cant find it and have done searches. Can anyone help ?

Thanks

What year and model do you have, and what problems are you having filling the tank?
 
its not a mod to make filling easier. its a mod to add about a quart of gas capacity to the tank.
pelicanparts has a thread or 2 on it, do a search. this forum might also have a thread on it- i don't know for sure.
 
On the 1100s, you can delete the "anti-spill" flapper inside the filler neck just by unbolting it; this gets you a little more capacity & makes filling easier.

On the 1150s, you can drill a couple of holes around the top of the filler neck; this gives the air displaced as you fill an easier escape path, making filling easier. I don't think it gives you more capacity, and the tank should be disassembled to do this (or you get hot metal chips inside, not to mention sparks during drilling!).

Members - more details?
 
On the 1100s, you can delete the "anti-spill" flapper inside the filler neck just by unbolting it; this gets you a little more capacity & makes filling easier.

On the 1150s, you can drill a couple of holes around the top of the filler neck; this gives the air displaced as you fill an easier escape path, making filling easier. I don't think it gives you more capacity, and the tank should be disassembled to do this (or you get hot metal chips inside, not to mention sparks during drilling!).

Members - more details?
The downside to this mod is that it can result in dumping gas into the charcoal canister, turning the charcoal into a slurry and blocking the tank's vent path.

The tank is designed to have a certain amount of air space in it. The fuel filler depth corresponds to the desired fuel height. The tank vent communicates with the air space. The tank vent is a combination vent and roll-over valve (intended to block flow throw the vent if/when the rubber side is not down). The vent hose has the charcoal canister in line to absorb fuel fumes (like when sitting in the sun with a full tank).

Put too much fuel in the tank, and expansion and/or jostling of fuel in the tank can put fuel into the vent hose, leading to slurry/line blockage. Once the vent line is blocked, the bike will build up vacuum in the tank as the fuel pump draws fuel out, until: (i) the pump can't overcome the vacuum and the engine starts to stumble/stall, and/or (ii) the tank collapses inward. Neither is a pretty situation.

If your canister is not present, then all you have to worry about is fuel spilling out of the vent line. Not my favorite smell. And given how hot my garage can get in the summer, and the fact that I fill up ~1 mile from my house, I don' t want to contemplate the idea of a pool of fuel under my bike inside my attached garage! :bolt

As you might be able to tell, to me it doesn't seem to be worth it to drill the neck for an extra 10 miles of range on a 250+ mile tank, given the potential problems the extra quart or so can cause.

Now, there will be a flurry of replies along the lines of "I did it, and have never had any problems!" Likely perfectly true. It's also true that others have. All I'm saying is gather all the information you can, then weigh the risk/consequences to make up your own mind.
 
Thanks for all the replys. I did drill out the neck and also did a canisterectomy. I am glad i did it. It makes it easier to fill the tank and when i know that i am going to park soon i dont fill it as full. I not only drilled a couple holes in the top of the neck but also drilled out the bottom to make it full size instead of just large enouph for the unleaded nozle. Also relocated my fuel filter externally.

oh its an 02 r1150rt.

thanks again for all the replys
 
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