GSXR 750 K1 - further electrical issues - generator and battery fail?

kippermitten · 5 Jul 2010 at 13:48

So leading on from replacing the rectifier in the week..

Saturday I charged up the battery, bike started and ran fine.
I put a volt meter on the battery and saw it hold at about 12.23v and drop slightly under load but seemed to recover to 12.23v.
So off I go only to have all electrical power die about 2 miles from work - right opposite the houses of Parliament to be precise!
Bump started and go to Vauxhall bridge and no juice at all.
AA dude(bike specific) turns up, I explained whats happened and whats been done...

In his oppinion the generator has died and most likely the battery now as he said when running you should see 13v and never a voltage drop.
His logic was - when the rectifier goes it forces the generator to work over time and the battery as well which will expose any faults in the generator and battery due to the increased load due to the failed rectifier.
So when Ive run it with the new rectifier and not seen correct voltage under load its because the generator and battery are most likely FUBAR.

Does this sound right? Any particualr way I can test if the genny or battery have defo failed?

Im about to order a new genny and battery as I need the bike back asap, cant afford a garage to do the work and am missing out on some FINE riding weather!

Any help appreciated!

fullspizz · 5 Jul 2010 at 14:45

Hmm, not too sure on this one.
It could be how the AA geezer told you, or it could just be some dodgy wiring.
When you bumped it, did you have no lights or power at all, eg dash, etc?
How far did you go before it packed in?
It does sound more like the genny or stator from what you describe, with no charge being fed back to the battery, which is constantly trying to keep all your electrics going on it's own.
I read somewhere (gixxerjunkies, iirc) that the genny doesn't actually properly start charging the system until it starts to rev over 5k, how true this is I don't know.
http://www.gixerjunkies.com/forum/showthread.php?t=85911&highlight=generator

There are ways that you can check the genny, I believe there are a few GSXR sites that show you what points to check with the volt meter to see if you are getting charge back.

kippermitten · 5 Jul 2010 at 16:43

I could barely see the lights on the dash and much clicking from under the seat relays...dont think its wiring as checked things throughly when putting in the harness and new rectifier.

Ive ordered a genny and battery and genny gasket as Id rather have all known new working parts to start off with.

I need a backup bike, anyone selling a 125cc+ scooter or 250 motorbike on the cheap let me know!

.one. · 6 Jul 2010 at 00:28

You should see a good 13v when running and a lift when applying the throttle as for the battery being ****** as well that's debatable.

1980s Gs550s and Gs1000s are known to burn out generators due to lack of oil > must be kept topped up regular but surly this is a thing of the past with the newer suzuki's.

kippermitten · 7 Jul 2010 at 11:30

I got the new generator and bits yesterday, the damm gasket I was sent is wrong! Id already cracked open the cover which mangled the current gasket meaning the bike is now in my works car park, leaning to the RHS against a huge HP server box, in gear, brake zip tied closed and front lower fairing off!

off to metropolis at lunch to get one, hopefully then ill be back on the road!

VFR_KID · 7 Jul 2010 at 12:57

Can you not get the battery to a garage and get it load tested? When my regulator/Rectifier went mate recommended getting a new battery as the other had been boiled. was showing fine on a few different battery charger thingys. but when mate load tested it all it said was change battery.

kippermitten · 7 Jul 2010 at 15:03

VFR_KID said:
Can you not get the battery to a garage and get it load tested? When my regulator/Rectifier went mate recommended getting a new battery as the other had been boiled. was showing fine on a few different battery charger thingys. but when mate load tested it all it said was change battery.

Eeep.
I didnt think of that...but normally isnt a battery boiling or failing is a result of another componant failing e.g. the rectifier and or generator?

VFR_KID · 7 Jul 2010 at 15:11

Not 100% sure on that one i would say yes as its being over volted. However im no electrician so could be talking a load of carp.

I was also told years ago that if a battery is completely drained at can have ill effects on it to.

Bigsy · 7 Jul 2010 at 18:39

On the VFR forum where R/R failure is common place they recommended you change the battery as more often than not they do get boiled, however you can usually smell when that happens. Even if it didn't boil a completely drained lead acid gets damaged if left uncharged for any length, I know this from experience with my car.

kippermitten · 8 Jul 2010 at 12:36

Yes, Ive heard that a number of times now.
Worth changing the battery every year so the rectifier and generator are charging an optimal battery hence less load on the genny and RR.
I put the new genny and battery in last night, rectifier is new as of last week....
14.5 volts constant, dips and recovers under load, perfect.
Bike feels like its had a upgrade

I think new sparks next, air and oil filter too.

fullspizz · 8 Jul 2010 at 15:08

Good stuff, glad you have got it sorted.
I think you need to take it for a good thrash now, just to make sure it's ok. Lol