- Knock your star-fangled nut down to about 45mm from the top of your stem (or the highest headset spacer, if you have spacers above your stem). You can use the provided 45mm dowel as a guide - the dowel should be just about flush with the top of the stem/spacer when the nut is at the correct depth. Ask your bike shop for help if you are unsure about this. You can use the provided bolt and nut to do this. Place the nut on the bolt and spin it down as far is it can go (if your bolt is fully threaded, spin the nut down about 20mm). Next, screw the bolt into the star-fangled nut as far as that can go. You can now carefully knock the star-fangled nut down with a hammer. The fork should be removed from the bike for this.
- By carefully pulling the wires apart, split the Reactor wire from the ends up until the tubing prevents further separation. This step is only necessary if you have a star-fangled nut with smaller gaps. The wire can remain together if you have a star-fangled nut or expander plug with a gap large enough for both wires.
- Feed one wire through a gap in the star-fangled nut and push it down the steerer tube until it comes out at the fork crown. This is possible even if the upper and lower gaps are not aligned, it just takes some wiggling and twisting of the wire to get it started.
- Do this again for the second wire, using an adjacent gap in the star-fangled nut.
- Run the wires down the fork and connect them to the dynamo hub.
- At the top of the steerer tube, plug the wires into the bottom of the Reactor. This is no polarity, you can connect them either way.
- Insert the Reactor into the steerer tube. A slight twist can help the wires go in smoothly. The Reactor should easily seat in the steerer tube; if there is resistance check the depth of the star-fangled nut - forcing the Reactor down with the bolt could damage the Reactor or the wires.
- Using the bolt provided, screw the Reactor into the star-fangled nut. If necessary you can use it to adjust headset preload, the same way you would with a regular stem cap. The nut should be removed at this point, it is only needed to help move the star-fangled nut.