How to: up the reliability of your Regulator Rectifier
 

This was a pretty simple mod I decided to do in the midst of rebuilding my bike. I know most regulator rectifiers fail because of heat. So I had some leftover silicone paste thats normally used on computer cpus for better cooling and applied that to the back side of the r/r (bought at any best buy or radioshack). The r/r is bolted to an aluminum plate that is bolted to the frame. All sit flush together. The point of the silicone paste is to promote the travel of heat from the r/r to the rest of the bike frame therefore keeping the r/r cooler. Not sure how much it will help but hey its easy and cheap and makes sense (at least to me). Sounds like good insurance to me.


I applied the silicone to the areas marked in red.
Attachment 42376



The r/r sits flush with the aluminum plates like so...
Attachment 42377

+2¢:
i'd grind down to the bare metal on the r/r before sandwiching it on to the aluma plate.

The r/r you have, has the finned heat-sink, so it's probably also a mosfet-type rectifier.
Those shouldn't give you any trouble. The problem ones had no heat-sink (other than
the frame mount) and were the older switching type electronics. You'll probably not
have any issues with the one you showed in the pictures.

Ern

regenerated thats a good idea.

maddhattr - i actually only did this write up because i had to replace my r/r because it fails after it heats up. so i got the one off my parts bike and did this extra measure to try to prevent the problem again. either way i see it as an insurance. nothing wrong with making something better right?

Absolutely not! That's what these forums are all about. Information exchange and tweaking our little beasties.

Thanks for sharing, Ern

Have you checked the output of the stator as well as checked it for resistance & shorts to ground? Seen people replace RRs when it wasn't actually the problem. As MadHattr059 said, the RR is cooled by the fins. Any extra assurance is a good idea though.

Stators checking good. New battery bout a year ago.

Just thought I would throw that out there. Reg/Rec has 12 checks & the stator has 9.

I wonder if wiring in a thin 12v (for computer use) fan would do any good. Looks like that area is deprived of air flow.

That's an amazing idea. I'm on that 1. Ill post pics as soon as the rectifier comes in. I have 2 of those fans and i never knew what I was gonna use em for.
I'm thinking right to the battery with a switch. Any ideas.

If I was going to do it I'd wire it to a relay that 1) tapped into the license plate light so it's only on when the bike is on and 2) to the battery with a fuse for power and 3) a switch in-line in case you need the fan off for some reason, like when working on the bike.

Nice call DarkNinja. Solid engineering plan.

Ern

I've been having some issues with my 03 954 not starting. As a result I've been trying to read through posts talking about possible solutions. I've looked at few that talk about R/Rs and most of them have been on how to modify them to run cooler. From reading the posts I have gathered that these modifications allow for a cooler running R/R which allows it to perform better. But I don't know what exactly the R/R even does and what exactly happens for performance to the bike with the modifications? Are the modifications done for preventative maintenance? Are they even needed or is this just a mod that people do that are geeked out about their rides and like to tinker with them (that would be me-even though I am very much a noob)?

Just as a disclaimer...I know this is a thread for "how to do something" but I figured since I'm still talking about R/Rs that it would be OK. If a moderator feels the need to move this please do so (not that you need my permission).

R/R is a regulator/rectifier. It regulates the current going from the stator to the battery, ensuring that it's not too much or too little. The stator + R/R is the same thing as an alternator in a car. Too much current and things start to cook, too little and things die from lack of power.

Honda is known for having really terrible R/Rs because they oveheat. One good reason they overheat is because Honda places them in spots where they don't get any airflow.

Simple fix (after you've confirmed it is your R/R): replace it with an aftermarket one.

It also rectifies the current from AC to DC.