got a 400ex. you charge the battery (2 monthes old, by parts unlimited) and it will run fine for a couple of hours. after those hours the bike spits and sputters. then looses its battery power, and will not start.

i just put a new amr coil and stage 3 cdi on yesterday. the stator is putting out juice. could it be my battery is just bad or what


thanks!

 

You answered your own question. If the battery will hold a charge, (you said it will for 2 hours or so) and then go flat, your charging system is not working. Why it's not working, your going to have to find out.

 

Do you have a volt meter?

If so, take a reading across the battery terminals with the machine off. Then take another reading with the machine running and revved up a bit.

 

A fully charged battery should be about 13.2 Volts. (fully charge the battery on an external 'battery charger') Now, with the engine running about 1/2 throttle the voltage across the battery terminals should be in the low to mid 14 Volt range (14.2 to 14.6). If it is only 12.9 to 13.0 Volts, it is not charging.

Usually only two things; Regulator/Rectifier OR Stator.

Disconnect the Regulator/Rectifier. Take the two 'Yellow' leads coming into the harness plug that you just pulled. Set Voltage meter to 'continuity' setting. Test 'Yellow to Yellow' = should have continuity. Test 'Yellow #1 to ground' = NO continuity. Test 'Yellow #2 to ground' = No continuity. If any of these three tests 'fail' then either the Stator or the wiring to/from it is 'bad'.

If the Stator passes these tests (which it usually does) - then the Regulator/Rectifier is 'probably bad' (98% certainty). (no real 'practical' way to test the Assembly - 'testing' would cost more than a replacement). Just go get a new Regulator/Rectifier.

 

ok, thakx. i will try these things. also would this have anything to do with my coil not sparking?