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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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1985 Honda Goldwing Limited Edition - 1995 Honda Goldwing GL1500 SE - 2012 Suzuki V-Strom DL1000
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The Compu Fire 55402 is another series RR to consider, 40 amp rating I believe. Smaller footprint than the SH847. Have one installed on my 1000 V-Strom, works well - replaced a Rick's Motorsport Hotshot RR.
 

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Discussion Starter · #63 ·
The Compu Fire 55402 is another series RR to consider, 40 amp rating I believe. Smaller footprint than the SH847. Have one installed on my 1000 V-Strom, works well - replaced a Rick's Motorsport Hotshot RR.
Has Rick's Motorsports RR failed on you?
 

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Discussion Starter · #64 ·

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1985 Honda Goldwing Limited Edition - 1995 Honda Goldwing GL1500 SE - 2012 Suzuki V-Strom DL1000
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Discussion Starter · #66 ·
Engine back on the bike, new Ricks-Motorsports Stator is in, plus SH775AA RR.
Hopefully this is the last stator replacement ever.. :)
 

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Discussion Starter · #67 ·
SH775 update:
I carefully monitored the Voltage provided by the SH775 in the last months:

As long as I keep the RPM below 7K, I get 13.5-14.0 volts on the SH775 outputs (connected directly to the battery). I get at least 13.0 at idle.

At 7K-7.5K the SH775 misbehaves: the voltage leaps to 15V for a few seconds every minute or so. This behavior becomes worse as the RPM goes higher and the weather gets hotter.

At 8K and above, the SH775 doesn't keep up and the voltage across the battery exceeds 15 (definitely over charging the battery and may cause lethal damage to the electrical components).
 

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Pim, I believe you did some testing with the alternator set up in a lathe. Did you find anything similar? Does Oshoshan maybe have a bad unit?
 

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Discussion Starter · #72 ·
R&R update:

I've had the SH775 for 2 years now, and about 10K miles. It worked as it did new - basically perfect all the way up to 7500 rpm. At 7500 and above, it would occasionally stop regulating and over-charge up to 15.5 volts. I obviously never stayed at that RPM for more than a second.

A couple of weeks ago I replaced the SH775 with SH847. Lo and behold, it provides a steady 14.1V from idle to 8000 rpm. It has the same connectors, so now electrical modifications were needed. It is physically larger, which meant that I have to remove the bracket that holds the various connectors. Yippie ka yay.
 

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R&R update:

I've had the SH775 for 2 years now, and about 10K miles. It worked as it did new - basically perfect all the way up to 7500 rpm. At 7500 and above, it would occasionally stop regulating and over-charge up to 15.5 volts. I obviously never stayed at that RPM for more than a second.

A couple of weeks ago I replaced the SH775 with SH847. Lo and behold, it provides a steady 14.1V from idle to 8000 rpm. It has the same connectors, so now electrical modifications were needed. It is physically larger, which meant that I have to remove the bracket that holds the various connectors. Yippie ka yay.
Is it uncommon for a regulator to not work up to redline? I'm just curious.
 

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Looked at the specs for the alternator system on the GL500/GL650. The alternator output is RPM dependent and apparently develops max power at 5000 RPM and delivers 252W according to the OEM service manual. After 5000 RPM the output goes down. This is how most motorcycle alternator systems work. The regulator/rectifier (RR) is not engine speed dependent, only monitors the electrical system voltage and compares it to the RR reference voltage of approximately 14.2 VDC. Voltage in the electrical system should not go above this, but if so, only a point or two. If the voltage in the system goes up to 15 VDC as mentioned, there is an issue with the RR, or a component of the electrical system such as the battery. A faulty battery will draw a lot of power such as the 15 VDC mentioned, have had this happen. Doing this for too long a time will damage the RR. The RR will work up to the red line, if not, there is a problem that needs to be found.
 
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Honda says the regulated voltage can be anywhere between 14 and 15V at operating RPM (13V at idle is about what I would expect) in all of the FSMs I've looked at (all normally aspirated CX/GL500/650 plus GL100 and 1100) so I would be very surprised if the Turbos are different.
I would be more concerned if the voltage across the battery is under 14V at 3,000 RPM than if it occasionally reaches 15V.
 

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Discussion Starter · #76 ·
Is it uncommon for a regulator to not work up to redline? I'm just curious.
An RR should be able to regulate up to redline. Not all of them do.
Traditional RRs (shunt types) short-circuit the excessive charge, causing high peeks of currents through the coils and the internal SCRs (mind you that once current runs through a coil you can’t really stop it without reaching high voltage). This shortens the life expectancy from both.
MOSFET RRs work differently. They anticipate the amount of power each rev will produce and start conducting only partial cycles, as needed. The result is a cooler and more efficient run. However, this means that the RR must be capable to anticipate faster as the RPM increases.
Both the 775 and the 847 are of the new generation. The 775 is the older model with limited performance. The 847 replaced it.
 
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Discussion Starter · #77 ·
Honda says the regulated voltage can be anywhere between 14 and 15V at operating RPM (13V at idle is about what I would expect) in all of the FSMs I've looked at (all normally aspirated CX/GL500/650 plus GL100 and 1100) so I would be very surprised if the Turbos are different.
I would be more concerned if the voltage across the battery is under 14V at 3,000 RPM than if it occasionally reaches 15V.
The battery’s spec is for 14.5V max. Of all the Hondas I have had (and still do), the charging system is always the weakest point. I never replaced water pumps or even headlights as much as I replaced RRs and alternator coils.
The fact that original RRs allow 15 volts doesn’t make it right. With my 775, the voltage would go even higher than 15V… definitely not recommend..
 
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