Is my number up? - R/R problems?

Tried to leave work last night and my battery was dead. I got a jump from a buddy and rode on home. Tried to restart when I got home and the battery was still down (solenoid clicking).

This is the battery that came in the bike when I got it last year. It always did seem a little weak (slow). It needed a bit of water and charging, but I haven't had any problems until now. I always plug it into my battery tender when I park at the house.

So, I left it on the tender overnight and tried starting again today. It fired right up. I started it maybe 6-7 times and it turned over and started every time. I was hoping it wouldn't start so I could just call it a dusted battery and get a new one. I put the VOM meter on the battery and I get ~12.4v with the key off. I started the bike and revved to around 5k, the voltage slowly climbs to about 13.3v and that's it. Book says that test should yield 13.7v - 15.3v (assuming a good battery).

So I guess my next step is to scrutinize the battery. I have a motorcycle hydrometer that I will use, but I've always had mixed results with those. Should I just go out and plunk down the cash on a new battery since I really don't know the history of this one?

Any other tips to help me out here?

Thanks!

 

I'm guessing your R/R is on its way out, I would say check all your grounds but I know you had the whole bike tore down so I'm assuming you would have covered those already. Being you don't know the history of the battery personally I would replace that @ the same time. There was a recent post on adding add'l ground & power wires to help even out the output voltage of the R/R was on a newer bike but would still apply. There are also detailed R/R diagnostics post somewhere as well,I would look them up but I'm still @ work & little busy @ the moment(on a break right now).

 

Thanks buddy. You are probably right about the R/R. I'm dying to go in the shop and start testing things, but I've been sicker than a dog today with some kinda stomach flu. uke:

 

Ok, just got done testing and it is looking like the R/R is bad.

First I pulled the battery and checked each cell fully charged with a hydrometer. All cells checked good gravity level (full charge). Fluid level was fine and no sulfication.

I put the battery back in and checked for leakage by disconnecting the negative lead only then checking voltage between the negative battery terminal and ground. Sure enough, pulling about 12.5v. This is why my battery went dead while parked. Some confusion here though between the factory and Clymer service manuals. Factory says 8v is normal for this test. Clymer says should be 0v and any voltage indicates a leak that will drain the battery.

So I unplugged the R/R and resistance tested per the book. Sure enough a couple of the tests show opens or shorts.

Here's the main thing that leads me to beleive the R/R is bad. When I unplug the R/R at the 4 pin block the voltage leak goes away. This leads me to beleive it is the R/R that has the short and is draining voltage.

All this combined with the low output level at 5k rpms and I think it's toast.

Does it sound like I checked everything correctly? Where is the cheapest price on a replacement? OEM or aftermarket makes no difference, just looking for cheap.

Thanks

 

Sounds just like when my R/R went, got mine brand new for Just over £100, You can pick them up for very little on ebay.