Andrew’s long-wheelbase supermoto is a unique mix of old and new, featuring parts from several Yamaha models

switchgear rework

The R6 switchgear has a hazard button which can be reconfigured to become the on/off switch

Rex stator

Fitting the new charging/ignition kit from the excellent Rex’s Speedshop

Andrew’sĀ Yamaha XT500 special

Every now and then someoneĀ brings somethingĀ wildly different into the shop. Meet Andrew, who has assembled a cunning mix of Yamaha parts around an XT500 engine and frame. It’s got XT660 mudguards, WR450 forks, a WR426 swing arm converted to twin shock, R6 switchgear and MT-03 silencers. Not to mention a Koso speedo, a powerful front brake and stacked headlights.

The trouble isĀ that YamahaĀ originally gaveĀ the XT feeble 6V electrics. The solution was a kit from Rex’s Speedshop which provides their carefully developed, made-in-Sussex CDI igniton and 12V charging. The kit is designed to plug into a stock bike, but with a few cable extensions it fitted Andrew’s concept perfectly. You don’t have to worry too much about ignition timing when you fit the stator, because you can fine tune it with a strobe and a special screwdriver (supplied) once the engine is running. (Rex’s website is an extremely usefulĀ bike electrics information sourceĀ ā€“ the tech section is crammed with hard-won knowledge.)

The switchgear needed wiring differently to turn the lights on and offĀ via the hazard switch. I’ve also found you need a three-pin flasher unit (ie with an earth pin) to operate the Koso dash’s indicator warning lights. To keep things away from the underseat exhaust as much as possible, most of the connectors and cables ended up at the headlight end. Only the tail light and number plate wiring, and possibly the battery, get within a few inches of the silencer box. Fortunately the Koso comes with a temperature sensor which will allow Andrew to keep an eye on heat buildup.

XTs have a reputation of being hard to start but this one kicked up easily, even without the decompressor cable connected. Rex are experts in designing CDIs that work over the full rev range, from kickstart to the redline.


Space is pretty tight on an XT thanks to the oil-in-frame top tube

headlight detail right

Most of the wiring action happens inside the brackets holding the twin headlights

battery area 1

The underseat pipe meant we decided to put the battery as far forward as possible, with a temperature probe to check it doesn’t get too hot