Is there any advantage to using a genuine R6 one over a replica Honda one?

Heat is the killer for any rect/reg. The claim to fame for a late model R1/R6 rect/reg is the FET technology they use that produces less heat. This FET technology is used by other motorcycle manufactures also but the R1/R6 apparently are the best known examples.

Having said this it is also necessary to use a rect/reg that has a current rating sufficient for the alternator fitted to the bike.

A rect/reg from any 400 should be suitable however some appear to be better than others, those having a metal base that allows efficient heat transfer to the frame being an example of a better type. The type with no or few metal fins and no metal base should be avoided unless you can find a way to get a good thermal connection between the rect/reg metallic surface and the bike frame.

Using a rect/reg from a larger bike simply takes advantage of the higher power and current rating because the larger bikes have larger alternators. If possible, good heat transfer to the frame should still be maintained just as an added precaution.

worthy reading

http://eviltwinsbk.com/forumz/index.php?topic=276.0
http://roadstercycle.com/Shindengen%20F ... %20kit.htm
http://www.triumphrat.net/speed-triple- ... grade.html

So if I could somehow make some sort of airflow to be aimed directly at the reg/rec whilst having it attached well to the subframe I could be onto a winner?

DaveLiverpool wrote:So if I could somehow make some sort of airflow to be aimed directly at the reg/rec whilst having it attached well to the subframe I could be onto a winner?

You dont need to.

As magg has said, overheating is the biggest killer of the reg/rec.

You need to look at WHY it overheats.

1. Most popular cause is an old / dying battery. All batteries age.. motorcycle batteries have it very hard. The plates are tiny and easily damaged. When the batteries become old they cannot take charge so good. This loads up the reg/rec so it gets overly hot.

2. Bad connetions like corroded earths and poor fitting plugs will put extra strain on the system as to overcome the resistance more current is required which causes the reg/rec to run hot.

The bigger units like the R6 (my NC24 uses a standard shunt type 1999 R6 reg/rec without fault) can dissapate more heat so will mask / overcome any weak points of the charging system / electrics.

Providing your battery is always kept fully charged (optimate it if you dont use it for more than a week or two.. batteries discharge overtime and the bike system isnt made for recharging a flat battery)

All your electrical contacts and plugs are good then the standard Honda reg/rec will be fine.

My NC30 is a 1989 K model and still has the oringal reg/rec fitted without any issue.

Id reccomend an R6 one anyway as you can pick them up cheaply secondhand and they wont die if you do have small faults with your bike.

DaveLiverpool, more air flow is good but can be difficult to achieve within the confines of the existing body work. if you run lights ON you will reduce the power loss in the rect/reg. Easiest mod to get the heat away is to make sure the thermal path at the chassis mounting point is a good as possible.