For all you reg/rec experts...

[vfrman]

Noted.

[magg]

Gepe, you appear to misunderstand the advantage of a MOS-FET rect/reg. Because they do not generate the same quantity of heat, they can be literally left hanging in space, as most bike manufactures are now doing.

The older SCR type rect/reg are the ones that respond well to flat mounting surfaces and heat transfer compound.

How have your rect/reg "heavily degraded after just 15,000km"?

[Morespeedvicar]

I think 'heavily degraded' is just posh for nakered......

Interesting that is getting that hot tho, i've thought about moving the reg to the plug in the vpiece and mounting it on the frame. only thought about it tho........

[gepe]

magg: With "heavily degraded" I meant to say that it no longer delivered the voltage that is required to fully load the battery. A new oem Shindengen r/r from David Silver Spares fixed it (no other issue).
The combination of r/r, generator, battery and wiring is very delicate and most people just replace one part with "an upgrade" without understanding the whole.
Compare this to wiring to headlights, some people think the engineers who designed it are idiots because the wire gauge is sooo small and there is a voltage drop and hey if I use thicker wire my headlights will shine brighter. But while they increase the light output from the bulbs they reduce the lifetime of their bulbs to let's say 20% because halogen lamps age very fast when they are driven with "over-voltage". There is a compromise between brightness and life span but most people modifiyng this don't consider that (well, maybe some do and are happy with 20% lifetime if they have brighter headlights).

Same with the charging system. If MOSFETs are used in a shunt type regulator and they don't get as warm as thyristor type r/rs, where do you think the excess heat is happening? Exactly, in the wiring of the alternator. The wire insulation will not like this. Not a good idea because that one is really expensive to replace.

Even the famous MOSFET Shindengen FHxxx r/rs are of the shunt type and they seem to put additional load on the alternator. See here: http://www.advrider.com/forums/showpost ... stcount=13
"It will help with problems of the R/R failing that some bikes have, e.g. if it can't handle the load of dissipating all the heat. But it will not help in our case, and might even make things worse. The MOSFET type shunting regulators run cooler than their thyristor counterparts because of their construction, which increases efficiency. But if you are not using the extra electrical power, and it's not being converted to heat in the R/R, the only way where it can go is the stator (and to a minor degree the [bike's] wiring)!"

Serial r/rs are something different but they are VERY rare because it is difficult to program serial voltage regulation with MOSFETs. In fact during my search for an r/r replacement I have only found two suppliers which are small companies with very small production runs. According to various forums, both have issues. And look at those serial monsters: they are huge and one even has a fan built in. They would not fit to my RVF or NSR without major modifications.

So, after a few days of searching the internet and reading, I have come to the conclusion that the charging system of a bike is a huge compromise and that due to cost, weight and size reasons most bikes can't have a charging system like in a car (which is ideal) and that the regulator is a wear and tear part and has to be regularly replaced. And even though I have a lot of expertise in the field of electronics I would not try to compete with Honda engineers and just leave it as they had designed it. It's too complex.

[krisztian_andre]

I've been looking for waterproof connector for my r/r and found these: http://www.ebay.com/itm/5-Kit-1-5mm-Car ... 4ab946a071
It says it has 1.5mm pins and is usable with 18 awg wire. Is this enough for the purpose?

[magg]

All bike charging systems are a compromise for the reasons you mention, including the expectation of the manufacturer than the life of their product will be no more than five years and preferably much less (they want to sell you a new bike as soon as possible).

Consequently the maintentance requirements are going to increase if we want to still have a reliable charging system well beyound the manufacturer's life cycle. Hence mounting the rect/reg using best thermal enginneering is a regular suggestion made on this forum, although using the newer MOS-FET rect/reg is a way of reducing the risk of a rect/reg failure.

The additional "load" from a MOS-FET rect/reg has non effect on the that already imposed on the stator/wiring etc. The same magnitude of current flow around the charging circuit, if one assumes that the stator produces 350 watts as a current source with its output limited to 14 under full load. The 1.5 volts from the SCR voltage drop x 25 amps (max available stator current) means approx 40 watts is consumed by the rect/reg. The rect/reg is simply a switch diverting the stator output back to its self and the heat is the switching losses. The wiring/connector issues are again a case of under engingeering to save costs, which can be improved, together with direct connection of the rect/reg output to the battery for improved charging.

Regarding lighting, most people I think would prefer brighter lights not dimmer, even if the life is reduced as you contend. Maybe the H4R halogen bulbs that are fitted to our bikes are less reliable that the conventional H4 or the bike environment is less conducive to long bulb life due to vibration. Halogen bulbs in car last many years and run at similar voltages. I doubt H4 bulb manufacturer's consider 13-14 volts as over-voltage given that all car charging systems operate in this range.

Regarding the new series regulators, in theory a superior design although compatible with the existing alternator design may be an issue, those currently under development by Shindengen may be the best option in the future.

[krisztian_andre]

What's wrong with the Compufire 55402?
http://www.amazon.com/Compu-Fire-Regula ... B0035U7LRM

[magg]

Although the Compfire unit has been around a while, have not seen any info regarding long term reliablity. You could be the first on this forum to try one. I have seen a technical evaluation that verifies the claimed advantages of the series design but again reliability was not examined.

[Neosophist]

Without getting involved in which unit is superior then I think that unless you can get a super fancy unit for cheap then I really wouldn't bother with anything more than a cheap r6 type reg/rec.

People seem to forget that the old shunt type regulators are supposed to get hot when they are working, its normal for them to be hot.

It's my theory (as well as many others) that neglect is the biggest killer of the stock reg-rec.

There is nothing wrong with it for general operation, but due to its small size it doesn't deal with excess conditions very well and often cooks itself.

Honda state that charging system is designed to keep a fully charged battery fully charged, not recharge a dead one.

* corroded connectors
* old battery
* neglected battery

These are the 3 big issues that hasten a stock reg/rec failure.

a lot of people have seen what happens to the genny plug when it gets corroded, it melts away becuase extra current is drawn to overcome the increase in resistance which makes more heat. The extra draw can and many times overloads the genny too which burns that out, a shorted genny may cause reg / rec issues if the output voltage changes oddly due to some bizzare shortings, but this is probably quite rare.

bike batteries dont live as long as car batteries, the battery on my old peugeot lasted 12 years before it needed to be replaced, even then it was ok in all but cold weather.

the car is used more than the bike so the battery was always kept fully charged, but over time the plates in the battery wear out from use, this is hastened in a bike battery as the plates are very thin to start with so they dont take well to abuse.

high revving bikes also vibrate more than most cars which puts extra stress on the battery.

I use standard batteries and replace them every 3 years to be on the safe side.

Worn out batteries dont take charge well and overload the reg/rec.

A well looked after battery can last much longer than 3 years I tend to keep them for but neglect such as allowing the battery to go completly flat, not keeping it fully charged can shorten its lifespan.

The stock reg-rec doesnt tolerate old batteries well so they usually go before the battery is completely dead.

R6 and the like units are much bigger so can take more heat and operate bigger batteries so even a struggling NC30 battery should be dealt with ok.


As long as you keep the battery charged up, clean the connectors with some contact cleaner as part of general maintainacne every couple of months and change the battery before its past its best then even the stock system is fine.

[JZH]

Interestingly, Shindengen now manufactures a series-type reg/rec for OEM use, which is now used on certain Polaris vehicles. (Pn. 4012941, approx. UKP85 all-in in the UK; used with Furukawa connectors, which can also be found on Triumph "link lead" pn. T2500676, UKP8.50 in the UK.)

The criticism of the CompuFire series reg/rec was that it was never designed to cope with the stator output from a high-revving Japanese motorcycle (it was designed for Harleys), but I've only ever heard of one CompuFire failure. I have one on my VFR800Fi, but I don't have many miles on that bike. I don't know if the Polaris vehicles (I think they're quads) are high-revving or not. Probably not! So, maybe series reg/recs are really not suitable for our engines?

Ciao,