charging issues xj

[chevy45412001]

ok been riding my bike for many years. the other night i parked it. got up to go to work and zipoo. check the batt,it was very low on liquid (i know shame on me )fill it with tap and through the charger on. Fires right up and off to work i go. After work zipo,get a jump fires right up off i go home (32 miles ) get home try to restart no dice. Well batts shot,so i buy new one for the bike fill it with acid and charge per instructions. rode back and forth for the last few days mon,tue and half today coming home pulling up to a go and stop light bang bike goes dead,no warning just like i hit the key. Now no power,it's 2 am in the morning call the ole lady to come wiyh cables, she gets there put on cables bang instantly fires as soon as i hook up cabes. drive it home no probs till i get in driveway start to play a littlepull in clutch and let the idle go to idle speed,lights start cto dim ,rev it a hair lights go bright,let off throttle and it dies no power whatso ever.NOW the question is whats my problem ? Does the xj have a voltage reg? i would think that is my prob as the bike runs as long as the idle is up.I'm thinking it's not putting the correct voltage back in the batt to charge. Help oh xs gods.sorry for the length but i have to ride this bike or quit my job do to fuel prices

[rover]

Hey CHEV, did you do the obvious and check all the connections? The grounds could really make life miserable for the charging circuits. When are you coming to WI? Love the handlebars.

[chevy45412001]

Hi Rover

other than just make sure they are tight thats about it.this problem came on like a huricane,no advance warning at all. Running fine when i parked it then when i start to leave whamo.And if i get it going proper i'll have to take a side trip to the land of cheesee (and Rover...lol)

[John]

Hey Big Bock. The regulator is under the tank, just ahead of where the tank bolts down. I have a couple of used ones if you need...

[rover]

Running fine when i parked it then when i start to leave whamo

Still could be a bad ground, or regulator, or stator or rotor. If the XJ has the same charging devices as an XS, I have everything you could need. If you take the side trip, remember to bring your cheese hat or they might not allow a FIB to enter WI. L O L. Your buddy Rover

[Jerry]

Well, the XJ does not have the came charging system as the XS. The XJ is equipped with a brush-style alternator; when you see an XJ note the extended right-side engine cover. There are 2 brushes in the set-up; either they are hanging up or are worn and need replacement.

Brush 1: 4G0-81611-10-00
Brush 2: 4G0-81612-10-00

Someone mentioned Parts-N-More has a better price than Yamaha on these.

The Yamaha manual recommends replacing these brushes every 10K miles, if my memory is not faulty....

Brushes are more likely culprit than regulator. Keep in mind the XJ regulator is rated at a higher current load than the XS, as the brush-style alternator puts out more current/wattage. The units are interchangeable mechanically, but if it is the reg I'ld look for an XJ oem replacement.

BTW, here is a link to the Yamaha parts catalog, which includes shop manual illustrations and part numbers:

http://www.yamaha-motor.com/star/parts/home.aspx

[rover]

Jerry, do the complete charging packages interchange? If the XJ has a higher output, would it be feasable to update an XS F to the XJ parts?

[Jerry]

I don't know if a full swap is possible, never compared both alternators side by side. I would have to defer to those who have worked on both models for advice.

[rover]

OK, Thank you. Maybe some expert will give some advice

[John]

The xj may have a better charging system, but the parts are as rare as rockin' horse poop. At least there are still some good used xs pieces out there. I'm sure that with a good wiring diagram to go by, a clever man could do the conversion.

[Winterhawk]

Doesn't the smaller red wire run from the starter solenoid, battery side to the fuse box? If the fuse holders are bad maybe it won't charge. Haven't looked at a wiring diagram yet but wired a couple of fuse box's last week.

[pggg]

Dont know about XJ's but if the rev counter dies or plays up on an XS, the battery's usually not charging also.

[chevy45412001]

procedure

ok i'm broke (can't afford cthe cd of knowledge) how do i check what with multi meter? one brush is longer than the other but both seem to move freely up and down. Seems that they are contacting the plate on the stator (or whatever they ride on ) as it is shinny on both spots respectivly. .are the brushes what actually take the current to the voltage reg.?My bike does run on the alt once started.thats why i guessed volt reg. Cause the batt is not being charged to proper voltage?

[chevy45412001]

new things

charged batt got 12.4 volts off bike. hook up batt. volts start going down quick.8.2 and sinking. bike wont fire even with jump now,turns slowly. cleaned both frame grounds and wires with a grinder,very clean and contact points.now i'm on too thinking starter selinoid? isn't that where the battery gets the juice to recharge? as the batt cable goes to sel. one one side then two smaller wires and the pos that goes to starter.I am not an electrican by no means . If it wasn't for 8 years of faithful service i'd put a bullit in it and get a NEW bike.

[DiverRay]

The battery should NOT drop that fast. Pull all the fuses out, hook up a charged battery, and check voltage. put fuses in one at a time, and check voltage after each one. See what part of the wire harness may have the short. If it is the main, it probably is the regulator. Next step is unplug the regulator, and check battery voltage. Does it still drop? Let me know.
Ray