Suzuki RV90 weak lights


Q: My new bike is a Suzuki RV90 running 6v magneto electrics. Needless to say the lights are feeble, the stop lamp glows dismally and indicators don’t. Apart from making sure all connectors and earth points are clean and the general wiring is in good order is there anything else that can be done to boost performance? Just having the indicators actually flashing would be good! Usually upgrading a 6v generator to 12v is relatively straight forward but can this be done with a magneto set up? What about using 6v LEDs with a suitable mod to the indicator relay to maximise use of the low power level available? I’m sure others would appreciate an article on this offering practical tips and methods to upgrade the system.

Rob Neal

Article continues below...

Enjoy more Classic Motorcycle Mechanics reading in the monthly magazine.
Click here to subscribe & save.

 A: This sort of electrical layout was deemed at the time to be suitable for smaller (by which we mean a cheaper system for cheaper) bikes, but at least it did work after a fashion and the functions such as brake light and indicators would have to conform to the then current legal requirements. So what is wrong? You have mentioned ensuring that all the wires, connectors and earths are in good condition but one change which can happen over the years is that the magneto rotor loses its magnetism to an extent. This can be corrected by being re-magnetised, which costs next to nothing. Check CMM’s adverts for a suitable supplier. Another point is to make sure that the bulbs fitted are to the correct specification. Ones which are too powerful will not improve lighting –quite the opposite, in fact. Finally, I am assuming that the battery (6 volts, 2 ampere hours) is in perfect order but wonder if it would be possible to change to one which is even bigger?  Although this would not increase the amount generated, the brake light and indicators are only used occasionally so there would be a bit of extra charge available in reserve.

Subscribe to Classic Motorcycle Mechanics Magazine Enjoy more Classic Motorcycle Mechanics reading in the monthly magazine. Click here to subscribe.