rec/reg

[littlebigman]

Hi chaps,
I think I need a new rec/reg. New battery dies in a day or two. What type, oem or after market?

[jim157]

99-04 Yamaha R6 reg/recs are a popular choice.

viewtopic.php?f=28&t=9698&start=0

[SmallFrowne]

Well depends really, a beefier aftermarket one will be better than oem but personally I've been looking at fitting a mosfet reg, which are much more reliable and run cooler. They are a bit more expensive and it seems the easiest way is to order a kit from the US. The main brand is shindengen, a japenese company, and some new bikes do get these as standard but not many, i think yamaha, kawasaki and honda fit them to the top of the range stuff. If you do a search for something like "shindengen fh020aa" you'll get loads of info and links to numerous other bike forums where people have fitted one for better reliability. You have to do a bit of crimping and soldering, and the mounting holes won't match up as standard but for me anyway looks the best bet (reliability if not price) at the minute untill somebody else comes up with a different mosfet reg, for cheaper/easier to install.

[magg]

Why not do some testing to identify the exact cause of your flat battery before you make a purchase that may not fix the problem.

[Neosophist]

If you service and maintain the bike and its battery properly even the original reg/rec is fine. The one fitted to my bike still gives out good voltage.

People have been using the R6 units for a few years now with little to no problem. They can withstand much more abuse than the OEM can take so seldom fail.

A switching regulator can have inherant problems of its own due to noise it can introudce into the electrical system, these old bikes were not designed with their use in mind.

But, with the R6 regulator being a proven choice tested by many people, cheap and easy to obtain and fit is there any need to spend more money than you need to?

Most but by no means all reg/rec failures I see tend to over-charge the battery and boil it away. If your battery is going flat your reg/rec may be ok but not be receiving power from the genny.

Either knackered genny or commonly the plug that connects the genny to the reg/rec can melt if crap is allowed to build up and the connection becomes poor, severing the supply from the genny.

Have you tested / checked any of this?

And why ask what type of reg/rec if your already considrering somethign different?

Plus do a search, there are dozens of topics already discussing this, and guides on how to fit the R6 reg.

[SmallFrowne]

Yes I should of said, as above, don't buy a new one unless you know it's a dud. Go to the documents page http://www.400greybike.com/docs.htm and seek out charging system check doc.

And yeah there may not be much point in fitting a fancy mosfet reg (overkill?), but I did say "personally".
Sometimes it is just nice to have a fancy new part that could increase reliability, and not leave you stranded (doh). I haven't bought one yet, I'm still trying to get the bike to run ok first before I even spend money on a cheaper reg/rec (R6 or something), so in the mean time I'm doing as much research into these things as I can.

Neosophist: Have you got any examples/other info to shed light on how the switching interference has had an effect? nc30's or otherwise, again just trying to build up a good picture before I make any purchase. Cheers

[jo]

If your reg/rec has failed so will the alternator and battery. You will most likely need to replace them all at the same time...

[Neosophist]

As I said above, I still use the original Honda reg/rec on my bike without issue.

I put an R6 reg/reg on my NC24 about 5 years ago now as the original one died due to a knackered battery. The R6 reg/rec was cheaper than a Honda replacement even second hand and is still faultless 5 years later.

I have no idea about any theoretical problems, you would need to identify a specific reg/rec your interested in and then try it or see if anybody else has.

All I can remember is somebody with an old bike was having firing issues due to interference from a switching reg/rec messing with the ECU at high speed. Perhaps it wont even be an issue on the NC30 but I have no desire at all to look into it as its something ill never do.

[magg]

Without any testing it is pointless speculating on what needs to be replaced.

A failed rect/reg can damage the battery by either undercharging or overcharging.

A dud alternator will have a winding shorted to chassis, an open circuit winding or a bad connection to the rect/reg and will always undercharge the battery no matter how good the rect/reg.

Failure of either unit is very rarely inter-related, so arbitarily or collectively replacing all the parts of the charging system is likely to be wasting money.

The switching action of a MOSFET rect/reg is not significantly different to that of an SCR type rect/reg and therefore will produce similar electrical interference noise, that can be managed by the ignition control unit, the only unit on an NC30/35 that would be susceptible to interference noise.

An SRC type rect/reg can be as reliable as the newer MOSFET type, provided there is a good thermal path between the rect/reg and the chassis support surface. Because the MOSFET type run much cooler than the SCR type they do not need a thermal path to extract heat and therefore can be mounted almost anywhere (most large capacity modern bikes have the rect/reg attached to the frame with rubber isolators).

[jo]

Failure of either unit is very rarely inter-related, so arbitarily or collectively replacing all the parts of the charging system is likely to be wasting money.

I must've just been unlucky the five times I've had a reg/rec fail on my bike for it to have had a failed alternator and battery as well.