LiFePo4 on an old bike - charging system?

[simonwri]

So I have an 80 Gs850 chopped and simplified. 8)

I run an antigravity 8 cell
Have new stator, rectifier and run a dyna s

anybody run similar ?
Some questions.

Do i need a specific charging system setup on this bike for this battery ( i used it for size as the bike is custom)

Can i run a total loss system ? aka no charging

Any other simple options? ???

My dilemma is a discharging battery ( either I have cooked it through the bikes overcharging or its not charged enough )
It holds 12.5vs and when running the bike it reads 13.4)

I just a lot of dead starting thats all ....very confused. I realise this is not plug n play stuff... but maybe its over my head!

 

[DohcBikes]

It is perfectly fine and normal for the bike to show a higher voltage when running.

As for the antigravity getting hot, yea it could be overcharging. Any lipo used with a standard bike charging system runs that risk. There are several forms of overcharge protection.

All that said, suzuki gs charging systems suck. What did you replace your components with? Have you folowed the charging system test procedures as outlined in your manual? Test the output voltage at the reg/rec with the bike running and the battery disconnected. Post results. Test each of the 3 stator legs on A/C at 3000 rpm. Post results.

Measure amp draw with key off. Post results.

 

[simonwri]

ok so i just ran the bike .

Output voltage on the Reg was a whopping 20v+- if this is accurate I have cooked my LiPo .
Its max charging is 14.6v

will come back with other tests

 

[jcw]

If this is the case, your regulator is not regulating. And you'll fry whatever battery you put on there.

 

[DohcBikes]

just because your reg rec is fried, which it is, doesn't mean your battery is bad. The advice above is correct, it will fry any 12v battery at 20v.

Does the battery hold a charge when disconnected?

Do you have a reg/rec as one unit or do you have separate units? if it is a reg/rec, is it a suzuki unit? They blow tornadoes for soup. Actually all zuki reg blow 'nadoes. I don't know what that means but its bad.

Thank you for doing that test. Continue testing and we will know a lot more.

 

[simonwri]

:-[Have just resistance tested the stator....

1-2 .9 ohms
1-3 OE
2-3 OE

1 phase was 8v @ idle rising to 20v when revved
other phases....nothing

Stator is stuffed.

Battery is:

unloaded 12.3v
main switch on 12.07v
headlight on 11.7v

more tests to come because the Reg is brand new..... or maybe the stator fried it too...

 

[DohcBikes]

Stator probably fried it. If it is putting out 20v its toast, one or more of the diodes is open.

Lets hope for the best on the battery.

Check with sonreir on the components to see if he has good replacements for that model. Otherwise electrosport makes a nice stator for the gs. Reg/recs are basically interchangeable as long as they have enough diodes for your system.

What you measured is voltage drop. Thank you. What we are also looking for is amp draw, which is a bit more complex and at this juncture not particularly pressing.

Excellent job of testing. If all posters had this attitude this end would be much easier.

The ups and downs of "old" bikes. Things break, we replace them with better things. You have a good bike, the gs' are excellent and overbuilt, save for the charging which is a nightmare. Keep working with it.

 

[simonwri]

ahh that makes sense - if 2 diodes are stuck open , they are the ones producing the 20+v and the 'normal' phase (the one reading 1ohm resistance is the one that was testing a max of around 13-14v?

The Reg was rebuilt by a guy from Gsresources (Duane?)
Rejigged honda thingy.

As i said its new , and now is going to be hard to test without an operational stator.

Thanks for your help very muchly ...this was doing my head in ...

I hope I can resurrect the LiPo , its worth 240 bucks!

 

[DohcBikes]

ahh that makes sense - if 2 diodes are stuck open , they are the ones producing the 20+v and the 'normal' phase (the one reading 1ohm resistance is the one that was testing a max of around 13-14v?

The Reg was rebuilt by a guy from Gsresources (Duane?)
Rejigged honda thingy.

As i said its new , and now is going to be hard to test without an operational stator.

Thanks for your help very muchly ...this was doing my head in ...

I hope I can resurrect the LiPo , its worth 240 bucks!

The reg rec is not hard to test, disconnected. There is a diode setting on your meter, they will need checked in forward and reverse bias, looking for .5 volts only one way on each phase. Red probe to black wire on the regrec and black probe to stator input wires one by one, then vise versa. If any diode fails any reverse or forward bias test, the reg rec is done. Check the net for testing details if you are still working, I'm too tired to post the whole procedure but the basics are here. I will check in tomorrow and hopefully by then sonreir also has some input.

 

[hillsy]

Your stator needs to be checked with the bike running at about 5K rpm.


Disconnect the 3 wires from the loom and you should see around 80-90v AC between each sets of wires at this RPM if the stator is good.


Pretty obvious from the fact you're seeing 20v at the battery that the regulator is gone but the stator may still be OK.

 

[simonwri]

Just tested the R/R ....dead
Both positive and negative sides kaput not even registering.

add it to the list of things to buy..... :'(

 

[simonwri]

Thanks Hillsy

The 20v reading was on the stator wires disconnected with bike at around 4000rpm

Its cactus

 

[DohcBikes]

Your stator needs to be checked with the bike running at about 5K rpm.

No it doesnt. His resistance checks were sufficient and clearly showed that the stator is not functioning properly. More than one way to skin a cat.

 

[hillsy]

No it doesnt. His resistance checks were sufficient and clearly showed that the stator is not functioning properly. More than one way to skin a cat.

Not really sure his resistance checks were accurate or not - first he said the 20v reading was off the reg then later it was off the stator (??).


Always a good idea to check the voltage output on a stator if you can regardless of any other readings.

 

[DohcBikes]

Reply number 5 gives the resistance values.

He also checked the output with the engine running.

His tests were sufficient. Regardless of your opinion.

Iys always a good idea to read the whole thread before arguing a point that is irrellevant.

 

[hillsy]

Reply number 5 gives the resistance values.

He also checked the output with the engine running.

His tests were sufficient. Regardless of your opinion.

Iys always a good idea to read the whole thread before arguing a point that is irrellevant.

The reason I responded was because I did read the whole thread - he said had 20v coming out of the reg/rec then changed that to the stator.


You should always test stuff fully if you can (like he has now) or you can end up making assumptions and chasing phantom issues. Sure that's my opinion but it's based in years of experience.

 

[DohcBikes]

Talking is fun.

He got .9 ohms on one leg of the stator, which alone, with experience, comma, should tell you that his results are accurate. The FACT that he got overvoltage on two legs of the reg out put and got open resistance readings on two stator legs should stick out like A SORE THUMB. And it does.

Chess, not checkers.

 

[simonwri]

So have ordered a new R/R

For those with a GS850 or similar shunt type R/R , apparently a reasonable upgrade is a polaris SH775 .

4012941 REGULATOR-3PH,35A,SERIES,105C

Modern series type R/R i Think

Hillsy , i will check the stator again tomorrow with the bike running ,

Just to confirm I got 20v+ on the reg output with it disconnected from the battery.
I also got 20v AC readings from 2 of the legs of the stator with the bike running, i think the other leg was even lower.

Thanks for all your input guys appreciate it .

 

[Sonreir]

For anyone else reading this thread at a later point, a more cost effective approach to replacing the Suzi GS R/Rs is to make use one one from a Honda GL1000. They're usually in the $20-$30 range (excluding shipping). Some wiring will be needed.

These will work all the way up through the mid 90s.

 

[hillsy]

Hillsy , i will check the stator again tomorrow with the bike running ,

Just to confirm I got 20v+ on the reg output with it disconnected from the battery.
I also got 20v AC readings from 2 of the legs of the stator with the bike running, i think the other leg was even lower.

No worries. Just to clarify my point you should always do both tests on a stator (resistance / continuity and no load voltage) to ensure you have diagnosed the problem correctly. The resistance / continuity reading you got INDICATES there is a problem but the no load voltage reading them CONFIRMS it. Basically, the output voltage of the stator is the money shot. You should do both tests on a new stator as well - don't assume just because it is new it is good and then move on....

It's important to make sure you have DEFINITELY eliminated any possibility of error when you're troubleshooting this stuff or you can end up chasing your tail in other areas (this is more for anyone else who reads this thread than for you )