Have you ever-had a gas cap refuse to come-off? Sometimes the cap will become so-rusted/gummed-up that it will not allow the retractable wedges to retract, releasing the cap. This is one way to do it, it doesn't cost-much, and you get-back your normal tank function. It does require a bit of work. Have you priced a gas cap from your local Yamaha dealer? Ron Ayres Motorsports: gas cap $115.49, fuel tank, $297.49; partzilla: gas cap $108.45, fuel tank: $297.37, so this is well-worth the sweat equity.
Someone will say, "just take it to a locksmith, and have them pick it!" The problem is that the mechanism is frozen due-to gum and/or corrosion, and a simple 'bump' to open the locked cap isn't possible.
Remove the gas tank. There is a 'how-to' for the procedure, I have not found it necessary to remove the swingarm, some methods mention doing that.
Measure down 5/8 inch from the top of the filler neck, wrap masking tape around the filler neck, to guide you in cutting off the filler neck, with the gas cap in-place. You can use a Dremel and a cutoff wheel, or a sawzall, I prefer the Dremel or other abrasive disc tool. Of course, do this with an empty gas tank! Draining the gas through the hex bolt drain port on the bottom of the tank is one way, or remove the gas level sending unit. After emptying the tank, use water to rinse the tank, and then use compressed air to dry it thoroughly. Then you can cut the neck with the Dremel cut-off wheel and mandrel, remember that 5/8 inch dimension.
The 5/8 inch will put your cut below the gas cap.
Once the neck has been removed, you can disassemble the gas cap by removing the two phillips-screws. There is a 'how-to' on refurbishing the gas cap, follow it.
At your friendly NAPA store, buy a 2" I.D. rubber gas hose, used for the filler neck on a 'cage' (car or truck). You will probably need to buy a foot, but you only need an inch. You could go to a wrecking yard and look for the correct size, or you could use a length of vehicle water hose, but the first is time-consuming, and the second probably isn't rated for use as gas tubing.
Use a file or your Dremel and and a drum-shaped abrasive stone to remove the sharp edges on the filler neck and the piece you cut-off. Make sure the notch on the cut-off piece of the filler neck faces forward.
Put the 1 inch piece of 2 inch i.d. gas hose tubing (NAPA part NBH 1045, gas filler hose, it doesn't have a steel helix in it (metal wire-reinforced), just rubber and some-type of heavy thread, probably cotton, so it's easy to cut. Do not buy the super-stiff metal wire-reinforced rubber gas hose! It is much too-stiff to make this repair!) over the filler neck on the gas tank. Put the cut piece of gas tank filler neck into the other end of the 2 inch gas hose tubing. You want to position the 1 inch piece of gas hose tubing where the middle of the gas hose rubber tubing covers the two pieces of the steel filler neck. Start to tighten the hose clamp (NAPA BK 705-1216), use the type of SS hose clamp which doesn't have the exposed serrations which can dig-into the hose rubber, and cut it. The rubber hose closest-to the gas cap should be about 1/4 inch-3/8 inch below the bottom of the gas cap.
This is where I use some safety wire to secure the loose end of the hose clamp. You won't tighten the safety wire until the hose clamp is tight, and neither the gas tank neck, nor the piece of the neck you cut-off, is moving-around. Then use the safety wire to secure the loose end of the hose clamp.
That's it, you can now replace the gas cap. Try it out for operation, it should easily release.
Sure, if you have the tool, you could TIG weld the cut-off gas tank neck back onto the gas tank filler neck. This is for those who don't have access to that.
If you use a Corbin seat, you can use a longer hose and put the gas cap closer to the surface of the seat. This is especially useful if you have the older Corbin 'flap' style seat, instead of the 'plug' style. You will need two clamps.
Someone will say, "just take it to a locksmith, and have them pick it!" The problem is that the mechanism is frozen due-to gum and/or corrosion, and a simple 'bump' to open the locked cap isn't possible.
Remove the gas tank. There is a 'how-to' for the procedure, I have not found it necessary to remove the swingarm, some methods mention doing that.
Measure down 5/8 inch from the top of the filler neck, wrap masking tape around the filler neck, to guide you in cutting off the filler neck, with the gas cap in-place. You can use a Dremel and a cutoff wheel, or a sawzall, I prefer the Dremel or other abrasive disc tool. Of course, do this with an empty gas tank! Draining the gas through the hex bolt drain port on the bottom of the tank is one way, or remove the gas level sending unit. After emptying the tank, use water to rinse the tank, and then use compressed air to dry it thoroughly. Then you can cut the neck with the Dremel cut-off wheel and mandrel, remember that 5/8 inch dimension.
The 5/8 inch will put your cut below the gas cap.
Once the neck has been removed, you can disassemble the gas cap by removing the two phillips-screws. There is a 'how-to' on refurbishing the gas cap, follow it.
At your friendly NAPA store, buy a 2" I.D. rubber gas hose, used for the filler neck on a 'cage' (car or truck). You will probably need to buy a foot, but you only need an inch. You could go to a wrecking yard and look for the correct size, or you could use a length of vehicle water hose, but the first is time-consuming, and the second probably isn't rated for use as gas tubing.
Use a file or your Dremel and and a drum-shaped abrasive stone to remove the sharp edges on the filler neck and the piece you cut-off. Make sure the notch on the cut-off piece of the filler neck faces forward.
Put the 1 inch piece of 2 inch i.d. gas hose tubing (NAPA part NBH 1045, gas filler hose, it doesn't have a steel helix in it (metal wire-reinforced), just rubber and some-type of heavy thread, probably cotton, so it's easy to cut. Do not buy the super-stiff metal wire-reinforced rubber gas hose! It is much too-stiff to make this repair!) over the filler neck on the gas tank. Put the cut piece of gas tank filler neck into the other end of the 2 inch gas hose tubing. You want to position the 1 inch piece of gas hose tubing where the middle of the gas hose rubber tubing covers the two pieces of the steel filler neck. Start to tighten the hose clamp (NAPA BK 705-1216), use the type of SS hose clamp which doesn't have the exposed serrations which can dig-into the hose rubber, and cut it. The rubber hose closest-to the gas cap should be about 1/4 inch-3/8 inch below the bottom of the gas cap.
This is where I use some safety wire to secure the loose end of the hose clamp. You won't tighten the safety wire until the hose clamp is tight, and neither the gas tank neck, nor the piece of the neck you cut-off, is moving-around. Then use the safety wire to secure the loose end of the hose clamp.
That's it, you can now replace the gas cap. Try it out for operation, it should easily release.
Sure, if you have the tool, you could TIG weld the cut-off gas tank neck back onto the gas tank filler neck. This is for those who don't have access to that.
If you use a Corbin seat, you can use a longer hose and put the gas cap closer to the surface of the seat. This is especially useful if you have the older Corbin 'flap' style seat, instead of the 'plug' style. You will need two clamps.
Last edited:
