Greating Brother and Sisters, I have a 95CBRF3 bone stock. It's been running great, sounds good and then I woke up with a dead flat battery. I attempted to recharge the battery by throwing it on a charger and when I removed it, I saw it was a factory battery. Yes, 12 years old. Not bad life for a battery. Got a new one, did the whole eight hour charge thing per the instructions. Bike ran great for about 14 hours comig back from a 350 mile trip the bike started missing hard, then would only idle, then died. I trailered the bike back and checked the battery. The new battery was shot. It would'nt take a charge. After a check of this site, I found that a voltage regulator may be the problem. Got a new reg from ebay for 36 bucks delivered. Replaced the battery, pluged in the new reg and everything was working fine again. With the exception of the regulator was wicked hot after only running for ten minutes or so. Does the regulator get that hot? Is the plate the mounts the reg some kind of heat sink. Voltage meter reads 14.3 to 14.7 at 5000 rpms with the new regulator. I'm guessing that must be pretty close to normal operations.

I hope it's not a bad stator. Those go for big $$.

 

Sounds like everything is ok, the reg is not something you would normally check day to-day, ok. Wot wears em out is exactly that, they git hot man. Believe me, if you felt your old reg before, it would have been the same (although they do get hotter as they go south) My battery went for 8 years, and probably would have gone longer, but you assume that when its that age & it goes flat, you replace it, same with you I suspect, its a bugger cos a new Yuasa is a decent slice of change, especially when you to get a new reg as well.
I got a heavy duty unit, requires a slight mounting mod, but the heat sinks are big enough to disperse the heat. With that in mind, put away a few bucks for the day that the replacement packs it in.

 

When i replaced my r/r a few weeks ago it too was getting hot as hell i was extreamly cautious about it because i diddnt want to fry a second one, but i rode past a local cycle shop and asked they said its supposed to get pretty damn hot, that's why it's mounted where it is.....soooo i just left it up to fate, and so far (3K miles later) all is well

 

I thought about ordering a slab of copper from a computer store. You know the heatsinks you use when overclocking? I wonder if that would be any good...

Stay tooned!

 

The main problem with the F3 would be the R/R. It get really REALLY hot. I think it's a combination of things (Small Cooling fans, bad connections, small wires). Mine went out, and I decided to replace it with a GSXR R/R. Bigger cooling fins. I had to soder all the wires but it was really easy. Haven't had a problem sense. but it's only been 3 mouthes. *Knock on wood*. Hit me up if you want to try it out, or find the tatorial for the change, if your R/R goes out again.

 

Thanks for the your feedback. My F3 is running well and continues to charge. Must just make a lot of heat converting DC to AC back to DC. I would agree that some sort of finned heat sink or a little fanmight make the part last longer than the heat sink they have in place on the bike right now. But, the first part did last twelve years! What more did I want?

THanks!
C

 

Some people fix cooling fans (as LlanoSVstated) off a computers processing unit to it. These can be bought very cheap from any computer shop. Dont worry though the reg/rec is meant to get very very hot, your first post was right, the metal plate is a heat sink used to dissipate the heat from the reg/rec to the frame of the bike and cool it a little.

 

The stock unit and the OEM replacement part were never "meant" to go on that particular application, which is the initial cause for the overheating. There is a store on ebay that sells a really good aftermarket unit. More internal diodes, aluminum backing instead of that crappy rubber, and better cooling fins. Hope this information can help someone out.

 

A lot of people use Gixxer one.
Here's the write up of my problem and possible solutions advice:
https://cbrforum.com/m_199676/mpage_.../tm.htm#213937

 

I just bought my '92 F2 a few weeks ago. I knew it had a bad R/R when I bought it. I bought a used R/R on ebay that came from an '05 GSXR 750, and soldered it on. It still gets really hot, but I checked its ouput voltages, and they are within spec. This weekend I am going to wire up a computer cooling fan for it. Does anyone have any good suggestions on where to wire this to? I am unfamiliar with the wiring of the bike and any hints would be good. Thanks a lot.