If you want a quick and easy fix for that leaky Honda fuel petcock here's what I did to one which has been working for 6 months without leaking. The simple proceedure involves drilling the two rivets out, flipping the rubber 4 hole washer over, polishing the selector plate or lapping it flat, and replacing the original rivets with screws.

This is not Rocket Science

I took a #36 drill bit and drilled all the way thru the two rivets that hold the plate on that holds the fuel selector lever plate in place in the petcock.
I used a 5/32" drill bit to drill away the rivet heads that remained after the #36 drill did it's work.
This allowed removal of the plate, lever handle. plastic washer and spring washer.
When I looked at the 4 hole rubber washer/seal that was under the selector lever plate I noticed that it had flat spots on the raised edge around 3 of the holes whose size correlated with the width of the band on the back of the selector lever plate.

This photo should show the correlation between the outer ring on the back of the lever selector plate and the flat spots.

Here's a photo of the reverse side of the rubber washer/seal that shows that it's almost identical to the front side, except it doesn't have the flat spots caused by the selector.
This seal is approximately 27 mm in diameter and the holes are approximately 8 mm.
Which leads me to think that a quick fix may be to simply flip this 4-hole washer/seal over, reassemble the selector lever plate and use the petcock.

To see how I replaced the rivets with 6-32 Allen head screws please see the Next page