alternator or diode board or what?

[Semper Gumby]

All my bikes come home and get hooked up to a Batterytender every time.  Makes the batteries last longer.

http://www.batterymart.com/merchant2/merchant.mvc?Screen=CTGY&Store_Code=BM&Category_Code=deltran-battery-tender-battery-chargers&SortBy=&show=48&pl=&ph=&char=

My R65 has a Odessy PC680 in it and as such it gets the big charger.

http://www.batterymart.com/p-battery-tender-plus-12v-5a-wp-battery-charger.html

If you get the AGM battery then you really need the bigger charger.  I had a regular 1.25 Battery tender let my Pc680 get discharged!!!!

(Love the Pink battery Tender.  Just in time for Christmas...)

Good Luck,

[GrimReaper]

The battery is YUASA not a sealed type. should i open the six caps before charging

[Barry]

Not really essential providing there is a vent tube which is the normal arrangement. You might want to remove them to check if a top up of water is required.

[Semper Gumby]

How long has that battery been in there?  If it's more than a year then its probably time for a new battery.  But here is the drill....

Not necessary to put the caps off to charge.  I would pull the battery out of the bike and charge on the bench though.  When they get cooking the make a lot of gas.  Kind of caustic to the metal parts on you bike.  

Make sure each cell is filled to the bottom line with fluid.  
If you need to add water to a cell make sure it is distilled (steam Iron) water.  Never use tap water.  

Charge the battery on slow overnight (if it is a multi level charger).

When done check each cell with a specific gravity tester.  (Little eyedropper thing with little balls inside).  This will tell you how strong each cell is.  Get one from Autozone or Napa.  When a cell is good all the balls will float (I think - its been a while).  If even one cell is bad, throw the battery away and get an expensive but really long lasting AGM battery  - Odessy PC680 highly recommended.

If the cells check out.  Make sure each cell is now at the Full line (top up with distilled water) and put it back in the bike.

On a Deltran Battery Tender you need to check the fluid level every six months as the cells will "dry out".

Good luck.

[Bob_Roller]

Since I moved to the Phoenix area a little over 16 years ago, my commute is now 11 miles, 2 miles surface streets, 9 miles urban expressway, I haven't had any charging issues, until I added two PIAA 40 driving lights (55watts each) .

I put a charger on it Friday night, for about 6 hours before I use the R65 on the weekends for work .

The additional electrical load of the two PIAA 40 driving lights, is enough to cause problems, if I use them while in city traffic .

Here in the oppressive desert heat of the southwestern US, I would check the fluid level on the battery about once a month, until you see how fast it loses water .

I forgot about checking specific gravity of each cell, it's been 10 years since I've had a serviceable type battery !!!!!!

If the battery doesn't have a vent tube on it, install one, the metal seat pan will get eaten up by the gas discharge from the battery .

[montmil]

Only thing I didn't like about the Motorrad Elektrik kit, was the type of connectors that are provided  .

They cut the insulation of the wire, I personally didn't use them .

I dumped 'em, too. Used the "proper" technique.

I run Staab generic AGM that fit both R65's battery box perfectly.

Monte

[GrimReaper]

the battery is about 5 months old.For last month i ride the bike about a 5-6 miles a day in the city so i guess with all the traffic lights and stops it is not enough to keep the battery charged.i will try to ride tomorrow with recharged battery,if the problem occurs again will test the rotor.

[GrimReaper]

Well it looks like the voltage regulator is faulty.I recharge the battery and after a ride(about 40miles) i had the same problem.So i check the regulator.I followed the instructions from this site:
http://bmwmotorcycletech.info/testingvoltageregulators.htm

and the results are:
 With voltage regulator the voltmeter shows 13.1
 Without shows over 14
 
I ordered a new one -Borg Warner R588

Will post results as soon as i recieve it

[Ed Miller]

Was 13.1 your resting battery voltage?  Simple fix anyway.  

[GrimReaper]

Was 13.1 your resting battery voltage?  Simple fix anyway.  

13.1 around 4k rpm

[GrimReaper]

Turn the ignition key to the off position, or remove the positive battery cable again .

Place small pieces of paper between the brushes and the slip rings, place the leads from the multimeter on each of the rotor slip rings, you should get around 2.8 ohms .

If you get infinite resistance, the rotor is bad .

Just ran that test and the multimeter reads 0 ohms resistance.Is this means that the rotor is bad?

[montmil]

Rick Jones at Motorrad Elektrik offers a remanufactured rotor $90.00 (or $124.95 for a new rotor).
Send your dead one as a core exchange.   Monte

http://www.motoelekt.com/charging.htm

[Bob_Roller]

Sounds like the rotor has 'shorted' internally .

Not too uncommon, to have the insulation on the windings, which doesn't amount to much more than a coat of thin, varnish like material .

That coupled with the centrifugal forces try to move the wires around, along with age, and heat exposure breaks down the insulation, and then bare wires touching each other .

[GrimReaper]

I will order a new rotor from Rick tomorrow.The problem is i don't have a repair manual .Can u guys give me some advices how to use the special tool to remove and instal the rotor

[Rob Valdez 79 R65]

Sure.

This article will tell you all you need to know, including graphics!

http://www.airheads.org/content/view/194/98/