Shadow Ace Stalling

[Zaphod]

A couple of thoughts ...

Any 12-volt battery that is giving open circuit voltage less than 12 volts is dead. A fully charged battery should read 12.7 volts. It might be possible to resurrect it by hitting it with a 15 volt equalization charge. Make sure the electrolyte level is kept up.

My wife had a 1999 Shadow Ace for a while. We did a lot of work on it. At idle, the alternator did not produce a high enough voltage to charge the battery. Only when the engine was revving in the 2,500 rpm to 3,000 rpm range did the alternator get up to the requisite 14.3 volts normally needed. We even tried changing out the regulator, but it made no difference. We concluded the stator was worn, but that’s a big task we avoided by selling the bike.

 

[pumper316]

The best upgrade I did to my '06 Shadow Aero was to ditch the shunt R/R and upgrade to a mosfet R/R. It produced 14V even at idle.

 

[dwalby]

My wife had a 1999 Shadow Ace for a while. We did a lot of work on it. At idle, the alternator did not produce a high enough voltage to charge the battery. Only when the engine was revving in the 2,500 rpm to 3,000 rpm range did the alternator get up to the requisite 14.3 volts normally needed. We even tried changing out the regulator, but it made no difference. We concluded the stator was worn, but that’s a big task we avoided by selling the bike.

I think that was normal for that style of alternator/regulator, it needed to be revved up to produce 14v. Back in the UJM days they were all like that, until they started going to self-excited coils.

as pumper316 mentioned, he modified his to get a different charging profile.