98' R/R FH0012 overheating after (all) replaced

Hi there,
my first post on related with famous burning Regulator/Rectifier problem on gen5 VFR.
I got a bike 50k+ km, with VFRNess(?) already installed and RR wired to battery. But, after few years, in the middle of nice trip and 300km away from home, it stopped on the road and RR (not wires) was making funny smoke.

FH0012AA has been ordered, then new battery installed, then stator replaced with Rick's stator - and my current problem is an overheating FH0012. People has it "warm to touch", I have it "burn your skin off".

All voltages and resistances seems to be ok (went many times with troubleshooting topics on this forum).
But after a couple of minutes even on idle - R/R becomes burn-to-touch hot. Also tried another R/R - FH0010, same thing.
Took for a ride - after 10-15m of 100km/h highway R/R just turning off (built-in over-heat protection) and turning back on after cool down.

Tried with highlight on - no difference.

I ran out of idea where to look and what else to try to replace.

 

Hi and welcome to the Madhouse:welcome:!

OK - we try to offer a warm welcome to new Forum members but it looks like your RR is already warm enough!

If you have not come across the following thread - please read the first post (re known problem areas) and then give the charging system wiring and especially battery and stator/RR connectors a close inspection. Look for visible signs (or smell) of melted connectors or wires. If that does not reveal any obvious faults - then move on to do the tests set out in post #9 which is routinely referred to as "the drill".

http://vfrworld.com/forums/showthread.php/39277-How-to-fix-common-regulator-Stator-failures

Essentially Post #9 is a set of diagnostic tests to assess the charging system health and identify potential faulty components. You need to do the checks (at least twice) once with the bike cold and then again after taking the bike for a decent 20+ minute ride by which time things will be good and hot. Why? Well some components like the RR and the windings in the stator can test out fine when cold but, once hot - insulation can start to fail and instead of charging your bike can rapidly discharge your battery.

Basically all four elements of your charging system (Battery, RR, stator, Loom) need to be in good order, and sadly a fault in one, can cause damage in some or all of the others. Testing is only valid if you start with a healthy and fully charged battery - so make sure your battery is not on its last legs as that can force the RR to run continuously in high output mode. High RR output is normal for a short while to replenish the battery after a cold start, but the wiring will take a real beating if a duff battery forces the RR to operate in high output continuously. Most decent motorbike shops will be able to test out a battery.

If you do find an obvious fault - don't assume swapping out just that component has got the problem fixed - do the drill again (twice) to make sure other components of the charging system have not sustained damage.

Good luck and when you get a chance swing by the "introductions" section of the forum to say hi to the fest of the folks (PS the folks on here really like pictures so make sure you add at least one picture of your VFR in your intro post.




SkiMad

 

Ok, I speed-read skimad's post but the one thing I think was missing was that CONTACT POINTS must be tight wherever connections exist. Many remove the plugs entirely & just solder the connections together to avoid this issue. Otherwise , GREAT advice from skimad!

 

Thanks for intro SkiMad
I read that post and went through "drill". My problem is that charging system itself works fine - good V readings, good charging, no any melting or even hot wires. Non of usual symptoms people having. Just an overheating R/R.

I was thinking of some problem passing current down to ground, but even direct thick wire from R/R to ground/battery "-" did not make difference. Two faulty brand new FH R/Rs , heh?

 

If you scroll way down that stator checking links thread you will find comments from people who had issues with stuff from Ricks - I tend to suggest http://www.roadstercycle.com/ - oh and yes on the critical charging system connections if you have issues then consider eliminating connectors by soldered and heat shrink joins instead.

just my 2p




SkiMad

 

Where are you Defacto?
If in Sydney I can have a look for you.
Seems a bit strange to be so hot within a few minutes, but a faulty stator or R&R could cause it.
Not a fan of anything but an original Honda stator, R&R's are plentifull and most are OK as long as connections are soldered and a voltmeter is used to keep an eye on.
Stators can fail quickly, R&R's can give you a hint that all is not fine.

Sorry, just realized you're in NZ. That's what you get when you copy our flag.

 

You need to check actual voltage from your stator.

 

I expected the battery to be charged, but I had a no start scare and also played the R/R dance today. Turned out my battery was just low and everything tested OK. Nonetheless, I decided that I don't like worrying about when my R/R is going to die.

I soldered the wires. Done. I would suggest doing the same if you are hunting down a potential R/R issue.

Jose

 

Yes loose connections are a known issue for 800s which a soldered joint can eliminate. But if the battery was low, you should probably try to identify the cause? If its something obvious - like you accidentally left the parking lights on - then the battery may recover with a recharge, but a healthy charging system should be producing ample charge to prevent your battery volts dropping so low that the bike won't start.

Sadly batteries do not last forever and it might also be an early warning your battery will need replacement soon.

http://www.whitedogbikes.com/shop/content/11-motorcycle-battery-faqs/#batfaq9

:focus:

When operating properly an RR should safely dissipate any excess energy as heat transferred by conduction to the frame and via the cooling fins to the air passing by - certainly once the bike is moving an RR should not be getting dangerously hot. Whilst 2 faulty RRs does seem unlikely - these things tend to be manufactured in batches and you could have been supplied with two RRs taken from the same faulty production batch.

By comparison I have never seen anything but positive reports on stuff supplied by Roadster - so if you want peace of mind, albeit at a price, then maybe consider fitting a replacement from them. If that solves the overheat problem, then you may want to recover some of the cost, by sending the Ricks one back and ask them for a refund - as it does not sound like it is working right.

Take care



SkiMad

 

Stator/old R/R definitely had have some problems, can say from the look of it, but both has been replaced. Voltages are correct. I'll try to bypass connectors, but they were replaced before me and looks quite solid, no unusual resistance over them. As it's only part not replaced yet..

We are working on a new flag!

 

they should run hot. they shunt unnecessary current to ground

 

Yes. But how hot? It's a too big difference between "just warm" and "burning" after 5min on idle on MOSFET one. Even this could be ok, but I'm quite sure that automatic shutdown due overheat protection is not a normal behavior.

But would be interesting to compare if somebody has FH0012AA.