3en1 Battery Not Holding Charge

[G3o]

Hi, Sorry to make my first post about a problem but hey!

I bought the bike about a month ago and all seemed fine and dandy, went out on a long old ride the weekend after i bought it and, after a seriously fun ride, the bike fried the reg/rec and subsequently the battery, A mate happened to have a spare reg/rec in his shed so i replaced that and the battery, it was charging again and all seemed well, took it out for another ride checked the battery was still charged/charging and it was so all was well.
I left it for a week without being used, I've just gone outside to start it and the battery is dead. Hardly even enough charge to turn over, what i'm assuming is the EXUP valve servo under the seat?

Not really too sure where to start with it to be quite honest, my first thought is that its a short on the frame somewhere thats draining the battery but i would have thought that would show up with a volt meter over the battery terminals when the bike is off. If you get what i mean, Electrics are really not my strong point so any suggestions are welcome,
Cheers
Geo

[Evilchicken0]

I wouldn't have thought the servo would be at fault.

First thing is to visually chech and wiggle the wires, to see if there's anything broken. take off the genny cover and have a look at the windings, make sure the pick up's ok too and again check the wires. Check the reg rec again as that's the last bit to be put in the system.

If it leaves you stumped then consider taking the bike to garage and getting it tested, I know it's not in the spirit of the forum but if you don't know wha's wrong you might spend a lot on parts without actually curing the problem.

[G3o]

thanks for the reply,
probably could have worded it a bit better, wasn't saying the servo was the issue was just saying as an example of how little charge the battery had, it could barely turn the servo over.

will have a look over the genny today see if its in good order and have another check over the rest of the loom, just thought I'd ask people in the know in case there were any common places for wiring issues/shorts/etc.

cheers
Geo

[Evilchicken0]

Generally Yamaha electrics are ok.
Do you have a current draw on the bike .... an alarm or some other accessory ????

[G3o]

No there isn't anything thats a constant drain on the battery, Which is why its confusing me. The battery was fully charged and still charging properly when i got back from the ride on tuesday, i made a point of checking because i'd just fitted a new reg/rec.

I've not had a chance to have a proper look over it yet, I had another quick glance around it and the wiring under the front fairing looks like a bit of a rats nest but couldn't see anything that looks like it would cause a problem, no bare wires etc.

[G3o]

Been and had a good look round stripped off all the fairings etc. couldn't find any shorts or damaged connector blocks, stator coil seemed in good nick, no scratches/gouges etc.
The battery was down to just under 3 volts, i've got it back on the optimate and i'm going to fit it again once its charged, double double check that the reg/rec is still working and the battery is getting charge, then i will keep tabs on it over the next week and see what happens.

[Hogdigerdy Dog]

if your sure the battery and reg/rec are ok
then it sounds like an electrical problem and not the charging system,
could be draining to earth
or could be the big resistor is us,
not sure about the 3en1, but on the tj the resistor is next to the battery (looks like a white fuse carrier, but with big wires)
or an earth drain
fault finding "how to" below

http://www.mediafire.com/?c74i3kctvzz4l

[G3o]

Awesome, thats fault finding guide it brilliant, will have a go over it this week and see what it turns up.

[G3o]

Well i just spent the best part of today, from about 11 this morning til about 5:30 going over the electrics and trying to find what drained the battery and the verdict was....

... absolutely nothing is wrong...

Going to take it out in the damp and see if it causes a problem and then go from there seems slightly odd but hey ho

[G3o]

Just putting this in here to save making another thread, bikes been fine since the battery randomly throwing away all its charge, went out for several rides this week and not had any issues at all until today, Been out for about 3 hours and the reg/rec has blown again, I only replaced it with a brand new one a couple of week ago.

I know its a common problem with these bikes but surely even with my luck it should last more than 2 weeks?!!! Just wondering what the root cause of the problem is?
From what little i know about the electrical side of things, my guess would be that its a grounding issue because the rectifier body itself is the earth, as far as i can tell, opposed to having a separate wire for earthing? thus allowing corrosion etc. to build up between the reg/rec and the frame making a bad connection and cause excess heat to build up in the reg/rec?

But as i say that is only a guess!

The new reg/rec i bought had cooling fins on that i imagined would have helped, but evidently they don't solve the problem completely.

Assuming my above guess is correct, would putting a wire between the reg/rec and the battery or engine earth solve the issue?

Cheers Geo