Topic: Where/how to mount combo voltage regulator / inverter on 1978 cb550k?

[dvgibson]

I Recently bought a 1978 CB550K and the wiring is pretty bad.  Multiple wires with metal showing thru the insulation, cuts, and some hacks.  So, I'm installing a new wiring harness and fuse block.  I also bought the combo voltage regulator/inverter from common-motor.  Can anyone recommend how/where to mount this unit?  It is larger than the individual parts it is replacing, and has different mounting.  I've removed the left side mounting plate, and removed the old parts, but still not sure what the best way to mount the new one is? 

Thanks,

Dave

[newday777]

Welcome aboard the forum Dave from NH.
I haven't done it but here is a thread on doing it, you'll need to make a plate to mount it to, aluminum would be best.

https://www.sohc.co.uk/index.php?topic=19875.0

[calj737]

I've mounted them in the past on the backside of the original bracket. Took a bit of massaging, but it fit, sat beneath the stock cover, and left room for the solenoid.

[TwoTired]

If the old units work, why replace them?

[grcamna2]

If the old units work, why replace them?

Will this new unit the OP is considering installing be compatible with the bike's charging system and will it be an improvement over stock ?  I'm not sure and wondered if dvgibson knows;just trying to learn.  thanks,Bill

Also,if you haven't done this yet,clean All the electric connectors on the entire motorcycle system including the grounding spots to the frame;I do this on all my bikes and keep them maintained and use the stock charging components and never have a problem with charge rate.

[grcamna2]

I Recently bought a 1978 CB550K and the wiring is pretty bad.  Multiple wires with metal showing thru the insulation, cuts, and some hacks.  So, I'm installing a new wiring harness and fuse block.  I also bought the combo voltage regulator/inverter from common-motor.  Can anyone recommend how/where to mount this unit?  It is larger than the individual parts it is replacing, and has different mounting.  I've removed the left side mounting plate, and removed the old parts, but still not sure what the best way to mount the new one is? 

Thanks,

Dave

Welcome to the forum Dave.

[wolf550]

Seems like the old spot is a good spot
if you can bend some metal there should be plenty of space for it and a fuse block

[Deltarider]

Germans found out there are aftermarket REG/RECs which have the alternator work 100% all of the time and simply shunt the excess to the frame. I never bothered with replacing parts still working perfectly.

[dave500]

regulators for permanent magnet field type alternators work like that Delta and shouldnt be used on electromagnetic field types,the regulators on electromagnetics alter the voltage to that electromagnetic field increasing or decreasing its magnetic strength,thats how its regulated,but in an off/on way.

[PeWe]

Adjust the stock regulator if voltage is too low.
A voltmeter at front between gauges so the voltage can be supervised while riding
.
It takes a longer ride to see when it reach max voltage.
If charging too low or high, adjust core gap after all involved electrical connections have been cleaned from corrosion and verified to sit tight, completely seated.

Both my CB750 have the core gap between 0.80-0.85mm.
Less or more will cause charging issues.
Stock can work really fine.

[TwoTired]

Adjust the stock regulator if voltage is too low.
Stock can work really fine.

I will warn not to adjust until you are certain the vreg it getting very near what the actual battery voltage is at the vreg sense terminals through connectors and switches.

Because of the range of output the alternator has, the vreg is there primarily to protect the battery from overcharge.  As such it doesn’t adjust system voltage directly, but by maintaining the battery in a proper state of charge, when the alternator is supplying enough power to do so.   Only when the battery is at full charge, the system is under full load, and the alternator spinning at optimum speed, should you adjust the stock vreg to 14.5v.  Otherwise, you risk boiling the electrolyte out of the battery on long run cruises.

[Deltarider]

Oh, to verify my claim in the socalled 'charging insufficiency' discussion, I had decided to keep book for a while to precise on what I've repeated so many times:
I always return with a better charged battery than I took of with.
Here are the facts:
Battery is an over 6 year old Yuasa standard battery.
Last part of my rides is always within city limits: 5 minutes of 40 km/h max with three traffic lights.
Final part is more or less a pedestrian area. Another 5 minutes but speed is reduced to 25 km/m max with two traffic lights and 2 pedestrian crossings.
I have always measured in the garage. The lowest after a ride was 13,4 V on arrival right after I had killed the engine. Next morning battery read 12,8 V. Ergo: my claim was right.

[PeWe]

The voltmeter will show if voltage getting to high. Then adjust.
The adjustment I have found making good is core gap. Honda manual say 0.6-1.0mm.
Both my bikes needed in the middle.
0.6-0.65mm did not work as well as 0.9mm that gave another side of wrong

The max voltage screw set so it will avoid overcharging.

I have also measured voltage over battery with separate multimeter to verify the onboard voltage meter's numbers on bike. Idle to 5000rpm.

[Deltarider]

BTW, are there any experiences to report concerning rectifiers using Schottky diodes? I mean, as far as reliability and durability? Haven't heard much about them for a long time.

[PeWe]

My K6 has Schottky diodes installed. I used it for a while until the voltage decreased after ca 30 minutes ride, around 0.5V less.
Swapped the connectors back to stock rectifier that kept the voltage.

I swapped between stock and Schottky several times during a longer ride earlier this summer.

I have not investigated that further yet.
If connectors are involved or Schottcy circuit only.

The plate the circuit sit on was not very warm either. Warm, but not hot for electronics.
"Power transistors" of similar assembly design usually much hotter.

I will test again if the diodes will behave as I saw earlier.
I spent time to adjust the regulator trying various core gaps to see what happened with the charging.

A voltmeter between the speedo and tacho should have been stock design.

See charging and see in time when going bad due to corroded connectors, battery or avoiding too high voltage causing battery issue.

I also care about the Dyna-S ignition.