Installing the R1 Gauges - Tach & Speedo
The trick that the original author of the how to worked out really well was how to use the existing funtions of the tach to show information that is needed by the RZ. We'll go step by step for each component starting with the main harness wiring and all wire color functions are listed in the resources page for reference as is a wiring diagram for the original USA RZ. You'll need the following parts:
The image above shows the R1 upper headlight wiring harness that connects to the R1 gauges, as well as the original R1 motor, thermostat and some other connections.
The harness has to be modified by removing all the parts that aren't used in the conversion. You'll need the main plug for the cluster shown above and the rubber boot to keep out the weather.
You'll also need the thermostat sender plug. Luckily the original wires are easily long enough to reach from the cluster connector to the RZ head.
To remove all the wires not required, peel open the black tape and wrappings to expose the wires in the main trunk. Carefully follow the wires back from the gauge connector and snip them at the furthest point to keep the wires as long as possible.
When you are done you should have a revised harness that looks like the one above, with free wires for the gauge, and the original wires still going to the thermostat sender connection. All the remaining stuff is junk and can be thrown away or go back on eBay??
In order to have the R1 gauge temp readout work you'll need to switch out the existing RZ one which is located in the center of the cylinder head as shown above. Disconnect the single lead to the sensor and zip tie it out of the way as you won't need it any more. You'll need to drain the coolant to replace the sensor. The easiest way to do this is simply remove the two drain bolts in either cylinder. These face out away from the bike on the side of the cylinder sleeve. This won't drain all the coolant but it will get the level lower than where the cylinder temp sensor is located.
In the shot above the original RZ sensor is on the left and an original R1 sensor is on the right. I installed a copper washer between the head and the sensor just to be safe about leaks. It felt like the new sensor had a slightly tapered thread but it went in to the existing cylinder head hole with no problem. There is easily enough room for the top of the sensor. Before going any further now is a good time to refill the coolant and check for any leaks.
At this point you should physically mount the gauges to the bike so that you can make sure all connections are long enough. Plug in the connector to the rear of the cluster with the loose wires hanging out. I used a piece of metal from the new headlights as shown and while I am not especially proud of how it looks, it does the job for now.
The R1 tachometer needs just a single wire connection from the existing flywheel pick-up on the RZ. Since no wire exists from the flywheel to the gauges, you'll have to add one. The easiest way to do this is to find the 3 pin motor connection which is located near the battery/airbox on the right hand side of the bike. Run a new wire from the R1 cluster yellow/black wire and splice in to the white/green wire arrowed in the image above.