Homemade Riv-nut Tool

On 03/20/03 Dwayne Verhey (aka Torch) from the FJROwners online forum wrote this Web page describing how to use a homemade tool to install "Riv-nuts" into the Yamaha FJR1300's header pipes. This is required to properly modify the EFI's CO setting, like the European and OZ/NZ models allow.

Note: there are companion Web pages documenting how to install the Riv-nuts, how to do the Barbarian Jumper mod, how to adjust the CO setting.

Ok, maybe you are the kind of person who will never install another riv-nut again for the rest of your life. Do you really have to buy the tool to do just four of them?

No, but I wasted quite a few riv-nuts experimenting with other ideas before I figured out a reliable solution:

First, get a piece of scrap metal 3" or 4" long, and drill a hole in one end the same diameter as the bolt you plan to use as a plug. This will be your 'anvil' against which the riv-nut is compressed. The length allows you to hold it and prevent it from turning. (The shape is not important and as you can see, there are no points for neatness here. ;-)

Next, get a regular nut of the same size and thread. Mark the nut at one point as a reference mark.

You will also need a longish bolt (1 1/2" or 2") and washer. Assemble as shown here. (Note: that's a steel riv-nut being used in these pictures)

The washer may not be necessary if you are using thicker steel than I did, but here it is necessary to reinforce the 'anvil'.

Ok, here's how it works:

Insert the riv-nut into the hole. Snug up the nut finger tight. Note the position of your reference mark on the nut. Use one hand and a wrench to hold the bolt and anvil from turning. Use a second wrench to turn the nut clockwise 3 complete revolutions (now you know the reason for the reference mark!) It does not take a lot of strength to hold the anvil steady; as you can see, I used my fingertips. But it is important to hold it from turning. Earlier experiments using just washers usually resulted in the riv-nut turning in the hole before it was compressed.

Here's the finished product after 3 revolutions of the nut. Measured with a caliper, the installed length matches the installed length of the same type riv-nut installed with the proper tool.

Make sure the hole in your anvil is the same diameter as the bolt. The above photo shows an example of what happens if the anvil hole is too large.

Similarly, do not over tighten. Here you can see how over tightening distorts the pipe and the riv-nut, making a poor seal with an obvious gap. (Distortion was actually first visible at 4 turns.) Compare that to the neat, snug fit provided by limiting your enthusiasm to 3 revolutions. More is not always better!