Mounting Bracket Materials:   10 EUR Order set from me.
1. Custom  Adapter plate for 52 mm diameter

2. 2- 5 mm x 6 mm Set screws

3. Cateye spacer #533-8730

4. 2-1.8 mm x 6 mm pins

5. 1 - 4 mm x 14 mm pan head screw.

6. Cateye Reversible Bracket H-32

  Tools:
1.  Pointed punch, 2.  Power Drill with 1.6, 3.5 and 4.2 mm drills, 3.  2.5 mm hex wrench,  4.  Phillips head screw driver. 

Assembly might take up to 20 minutes to complete.

Center Cateye Spacer on adapter plate.   With a pointy object, make an indentation in the adapter plate for the hole position for the drill to center in.   If you buy it from me, it might come pre drilled. 

Drill a 3.5 mm hole through the adapter plate.

With a pointy object, make two more indentations inline with the first hole in the adapter plate.    Space them about 7-8 mm to the right and to the left on the center line from the first 3.5 mm hole.   

Note:  If the left hole is too far forward then the hole will land over the taper of the housing and the mounting stabilty will be reduced.  Make sure the hole will be in an area where the adapter sits flat on the housing. 

On the center mark,  drill a 4.2 - 4.5  mm hole through the adapter plate.   A 4.2 mm hole makes for a tighter fit with the set screw. 

On the center mark, drill the second 4.2 - 4.5 mm hole through the adapter plate

The tube has a identification stamp on it.   Assemble the mount over this area to hide the stamp. 

It might be best to first glue the adapter plate on the housing to help prevent it from rotating during drilling.   This will ensure the alignment is perfect for final assembly.   Two part 5 minute setting epoxy can be used with a C-clamp.   Sand the housing first to roughen up the surface  finish so that the epoxy will stick better.

Holding the adapter plate firmly against the housing, butted up to the seal channel, drill a 3.5 mm hole through the housing.   Make sure there is little or no gap between the shoulder of the housing and the adapte plate, else the adapter can easily rotate and cause the mount to be at an angle. 

Deburr any hanging material from the inside of the housing. 

Drive in the 4 mm x 14 mm pan head screw until the end comes out inside the housing.  This will help keep the adapter plate stable and in postion to drill the next holes.     It is important to keep the plate aligned while drilling as the drill wants to rotate the plate.  If the adapter plate moves then the plate will be mounted at a small angle and will not look so good.  Gluing it first is recommended to prevent a crooked mounting. 

Drill a 4.2 - 4.5  mm hole through the housing. Deburr the hole from the inside. 

Drive in the 5 mm set screw making sure to hold the adapter plate firmly against the housing.    Avoid gaps between the housing and the adapter plate.  The set screw should be flush with the inside of the housing.   If it protrudes too far it will be difficult to slide the lamp in the retainer ring in the housing.

Drill the second 4.2 -4.5  mm hole through the housing. Deburr the hole from the inside. 

Drive in 5 mm set screw making sure to hold the adapter plate firmly against the housing.    Avoid gaps between the housing and the adapter plate.  The set screw should be flush with the inside of the housing.   If it protrudes it will be difficult to assemble the lamp. 

Unscrew the pan head screw in the middle so you can assemble the adapter plate.

Option:   Glue Cateye plate to adapter with epoxy.    Be careful not to get epoxy on the mount quick disconnect slide. 

Align the Cateye spacer plate and drill the first  1.6 mm hole for the steel pin.  

Press-in the 1.8 mm pin in the hole to attach the Cateye spacer plate to the adapter plate.

Drill the second 1.6 mm hole for the second steel pin.  

Assemble the second pin in the second hole.

Remove the pan head screw.

Assemble the LED lamp in the retainer ring (23 mm).  The lamp will fit more easily in the side which was cut.  The uncut side has a tapper in diameter and the lamp will not fit so easily in it. 

Assemble the lamp and ring in the housing.   Make sure the lamp is sitting squarley in the housing.   Look at the gap between the housing end and the lamp to make sure it is about the same all the way around.  

Assemble the lamp connector on the lamp.   Orient the lamp until the connector from the cap  is perpendicular with the base.    This orientation is later important for assembly of the cap.    When the cap is assembled, the switch and power connector will need clearance on either side of the lamp connector.  

Here you can test the lamp before it is assembled to make sure the connections are good.

It is important that the lamp is perpendicular during drilling of the next 3.5 mm hole through the 23 mm retaining ring.    To make sure the lamp stays pushed against the end, use the old piece of tubing from cutting to press the the retainer ring down.    Drill hole, taking care not to drill into the LED lamp. 

3.5 mm hole in lamp retaining ring. 

Now start the 4 mm x 14 mm pan head screw.  

It will make its own threads in the adapter plate and the housing.    

As the screw pops through the housing, press the 23 mm retainer ring against the screw while driving it to get the screw to also thread it into the retaining ring.   

The screw will usually try to force the retaining ring up and not thread into it.    With a screw driver tip, apply force against the retaining ring to get the screw to "bite" into it and create the thread. 

If you did it right, then the package should like this.  There should be no large gap between the retainer ring and the housing.  

Assemble seal ring so that the cap slides with the lip seal and not against it. 

  Assemble end cap so that the switch is on the right and the connector is on the left.  The lamp connector has to fit between the the switch and power connector so this is the reason for the orientation. 

Test the lamp and then go riding!