Regulator Rectifier identification help!

[Mike149]

Okay sir will do, thanks for the help and i'll post up what readings I get from where. ...as soon as I get a multimeter!

[V4beermonster]

Hi there it's a standard fit net to many honda's I have one fitted to my seed Vfr it's a 5 wire reg/rect

[Mike149]

I think the problem has been sorted, a friend helped me out last night and identified some nasty corroded wiring on the way from the stator to the rectifier. Having changed that, we started it to find that she charged the battery nicely and ran at around 14 volts at 4k with maim beam on.

[Morespeedvicar]

Cool, pleased you got it sorted

[Mike149]

Well, I'm back with more grief! On the way to MOT the bike gave up, come to think of it it was the first time I had run it with the sidelights on and well when I came to a stop on the way there it didn't tick over, didn't turn over once tried and had to be bumped to get it to MOT. Do NOT ask me how it passed, the whole experience was rather hilarious.

Anyway, I'm back at my friend's house, the man who initially diagnosed the dodgy wiring from the stator to the rectifier.

Thinking that it was the rectifier we changed it for a chinese one bought tonight from a shop close by. It is definitely wired in correctly, in relation to the three yellows from the stator then the red and the green out of the rectifier.

the resistance has been tested from each of the coils and it reads 0.7ohms each. The resistance from each yellow wire to frame earth is infinity. So according to these tests the stator is not at fault. I also checked the plug down near the V of the engine on the right hand side and I am getting the same readings from the multimeter.

What is currently happening is the battery will read 12.1 volts. Once started it will run at around 12.9 to 13 volts when at 5000rpm. But, all the while, the rectifier is getting hotter and hotter. You can barely touch it without burning yourself! (this is the chinese one bought tonight)

We are now checking wiring which comes away from the rectifier, in case we find anything.

Any more help, advice or suggestions are appreciated :)
btw it's T - 76 hours until I leave for the Island, and I am DEFINITELY going on this bike. So it has to be something simple. hopefully.

[magg]

The rect/reg gets hot, it is how they function. What voltage do you get at the battery when running at idle with lights off, then high beam on. What voltage do you get at 5000 rpm with high beam on. How many times has the battery been run flat?

[magg]

Although the example below has had the battery wiring was changed to remove some inefficiencies, it is indicative of the battery voltages for a well functioning charging system.

idle:

No lights 14.0 volts
Low beam 13.3 volts ( expect 13.0 volts with 55/60 watt headlight)
High Beam 12.7 volts

RPM to achieve 14.6 volts:

No lights 2000
Low Beam 2500 (expect 3000 with 55/60 watt headlights)
High beam 3500

[NGneer]

The rect/reg gets hot, it is how they function.

The electrical charging system is a well known 'weak' area on the NC30. The OEM Reg/Recs wether due to age or poor design were (and still are) prone to overheating and subsequently melting the connector plugs....and in turn potentialy killing batterys and even ECUs on occasion. Like so...



When this happens (or if you are smart you do it before it happens) most people have changed the OEM Reg/Rec for either an more robust item with more finning to assit in the cooling from something like an R6 (similar to the one you had fitted origionaly). A give away of such a change is the in line splicing of the yellow cables - as per your bike.

IMHO - get rid of the Chinese Reg/Rec, before that dies and potentialy takes out mor eof your charging system, and refit the heavy duty item that was on there. Then go through the whole wiring run, clean all connections and make sure they are well connected.

Having done that go to the documents page (http://www.400greybike.com/docs.htm) and print of a copy of the "Generic charging system check list". Work through that step by step and it should either give you a positive health check - or at least identify which area you need to be looking at.

[magg]

"Over-heating rect/regs" do not burn connector plugs. No matter what type/size of rect/reg you fit, a burnt connector will occur when the contact resistance becomes excessive. Maintaining low contact resistance is easier with environmental sealed connectors, unfortunately many/most rect/regs are manufactured with connectors that are difficult/impossible to seal. Rect/regs that have flying leads can be modified by removing the fitted connector and replacing it with a sealed type.

Alteratively examine the connection points of the charging system as part of your regular maintenance schedule.

[NGneer]

Ok - I conceed that the 'heat' from the Reg/Rec itself does not cause the burnt connector plugs (I was trying to be concise) but the excessive heat build up in the OEM / Chinese copy Reg /Recs does cause them to break down, thus building up excessive resistance as they start and continue to fail, causing the damage to the plugs ...and potentialy the rest of the system.

Alteratively examine the connection points of the charging system as part of your regular maintenance schedule.

Agree totaly, and by doing so you will see any early signs of 'overheating' and hopefully be avble to rectify them before it becomes a major problem