Rex’s XJ600 Race Wiring Loom. Below are 2 examples of stripped down wiring schematics for XJ600 race wiring looms. There was a requirement to have a horn, which is why we show one fitted. Elements can be added or removed as required, for example if you intend to roller start or push start the bike, the starter motor can be removed.

You can buy the correct type of wires and connectors from www.rexs-speedshop.com 01580 880768 
 Firstly there are a few safety features you need to know about. Some XJ600s had a starter relay with only one small wire to operate them. This type must be replaced by one with 2 wires. On the standard bike there was an interlock relay to stop the starter motor from running when the ignition switch is off. You have removed all these interlocks. To give the system a basic level of safety a two wire relay MUST be used. This will prevent the starter motor turning with the main switch in the off position when wired as shown. Serious injuries may result if the engine is started or the starter motor runs when not intended. A 20 Amp fuse must be fitted as shown. This ensures the battery is separated from the loom if a fault develops. The generator can only produce a few amps, in comparison the battery can supply several hundred and cause a huge amount of damage, therefore the regulator should be connected after the fuse as per the diagram. XJ Models with dual pick-ups. Take care when wiring in the pick-ups on models with dual pick-ups. These use the same wire colours for both the HT coil control and the pick-ups. The easy thing is to remember the HT coils go to the same plug on the ignitor box as the power wires. The pick-ups have their own plug with NO wires for powering the box. Single pick-up models use different wire colours on the pick-ups. Tips to make the job easier Use non adhesive tape to wrap the loom. Traditional ‘insulation tape’ turns in to a sticky mess. Its use should be limited to securing the ends of non adhesive tape (if heat shrink is not available or practical). Use Japanese type bullet connectors with rubber insulators or motorcycle block connectors NOT the red or blue type car terminals. Get a proper ratcheting crimp tool, after you’ve done 20 crimps with the budget pressed steel crimpers, you’ll be ready to throw them in the bin. An automatic wire stripper is a luxury but makes the job so much quicker and easier Finally This is intended as guide intended only for fully qualified and experienced auto electricians, it is not an instruction manual to teach motorcycle electrics to beginners. Unfortunately we do not offer technical help on free to download guides or DIY wiring loom builds. Our technicians will not be able to speak to you on the phone to trouble shoot home built looms.

Rex’s XJ600 Race Wiring Loom. 


Single pick-up loom

Rex’s XJ600 Race Wiring Loom. 


Double pick-up loom

Rex’s XJ600 Race Wiring Loom. Charging system Some models had a ‘field controlled’ type of alternator, this is the better alternator. Permanent magnet alternators are always on full load absorbing the maximum amount of power from the engine.This is because the only way to control the output is to either use the power or dump it to earth, placing a heavy electrical on the generator, hence they always absorb a lot of HP. Field controlled alternators can ‘turn down’ their output and off load the engine when little power is needed. Field controlled types are a little more complicated, but not much as there are just a couple of extra wires. The brown and green wires running down to the alternator supply power to the field (often called an exciter winding). If you have a permeant magnet alternator just ignore the green and brown as there are no field windings just the 3 phase windings. The regulator will still need a connection to the brown but the alternator will not have green and brown wires, just 3 white or yellow wires.