Bad Reg/Rec ?

[michael5035]

So my 1981 was running fine then started to sputter and backfire on acceleration. I thought it was carbs so cleaned them and no change. Then while idleing i unhooked the regulator rectifier and it ran smooth and reponsive again.So I ordered a new R/R and hooked it up and it runs terrible again. So im wondering what to do now. Note I have put on a new rotor and brushes and battery is good.

 

[retiredgentleman]

So my 1981 was running fine then started to sputter and backfire on acceleration. I thought it was carbs so cleaned them and no change. Then while idleing i unhooked the regulator rectifier and it ran smooth and reponsive again.So I ordered a new R/R and hooked it up and it runs terrible again. So im wondering what to do now. Note I have put on a new rotor and brushes and battery is good.

You have likely come across a common failure that happens on TCI bikes. The TCI ignition uses a small magnet that is embedded into the alternator rotor. That small magnet is very important, because it triggers the TCI pick-up coils.

That small magnet's magnetic field shares the same real estate as the rotors magnetic field. When the small magnet was newer, it was strong and all was well. However the small magnet gets tired and weak over the years. Now the rotor's magnetic field is over coming the small magnet's field. That's why unplugging the rec/reg , removing the rotor's field, allows the the tiny magnet to once again trigger the pick-up coils.

Its been told that Radio Shack sells a tiny magnet that can be glued over the stock magnet and the TCI will once again work correctly.

For more info, try a "Google custom search" in upper left corner.