FR 400R ignition problems! -------------------------------------------------------------------------------- Hello, all! I have some problems with my VFR 400R 1988. The sparks are small and yellow insted of blue and powerful. I have measured the coils (4) and they are all 3,2 Ohm and they all have the right volts when the ignition key is turned on. The pulse generators have 389 Ohm (should be in the range of 450-550 Ohm) each but leaves only 1-1,7 volts when cranking the motor, a little bit to low (at least 1,8 volts or above should it be according to a repair manual for later models). Could this be the problem? Does anyone know a way to check/measure the spark unit box? Best wishes to you from Sweden
Do you have the correct battery and have you checked to see if it is fully charged? If the battery is dying when the bike is running you might have a generator problem.
Are you using New plugs? if all the coils have the same weak spark spark then you can generaly rule them out. would definitly check the battery. if its a TPI ignition system(i know 3rd and 4th are) then the battery voltage plays a huge role. it needs at least 10.5 volts just to turn the brain on. so fully charge your battery and then check your charging system as well as the power wire(should be getting battery voltage) and check the ground wire(should have no more then 1 ohm to chaiss ground) at the brain. also check the resistance of the pulser coil at the brain. hope i helped.
I have found the problem with my starting issues. Corrosion where the cables connect at the starter relay so it got current but not well enough. Thanks to you that have answered this thread.