Topic: My 1975 cb 750 Build

[PPG9944]

Going to try to use this regulator rectifier off a 2001 magna as just the rectifier instead of the stock unit. 



Compared the 2 wiring diagrams though and the rectifier on the stock set up has a ground wire.  This one does not.  Can I use the wire from the regulator section of the unit as a ground wire?

[evanphi]

Any ground wire will work. They all go back to the same place... the frame.

[PPG9944]

I'm really hoping this works as the rectifier haha. I'm pretty lost with this wiring stuff.  I'll grasp it eventually

[evanphi]

You know you can get a solid state reg/rec combo unit that is wired for the stock harness?

http://4into1.com/ricks-motorsport-electrics-honda-rectifier-regulator-combo-cb350-cb400-cb500-cb550-cb750/

[PPG9944]

You know you can get a solid state reg/rec combo unit that is wired for the stock harness?

http://4into1.com/ricks-motorsport-electrics-honda-rectifier-regulator-combo-cb350-cb400-cb500-cb550-cb750/

I have seen that before but I had this unit lying around.  Trying to keep the costs down and get creative is what I'm after really. I'm hoping it works.  If it doesnt I'll be able to wire the stock unit in.

Any good resources on how to build a wire harness?

[PPG9944]

This makes me proud.



Still lots more to do, routing and rerouting wires but it's slowly making sense.

[PPG9944]

YEAAA!  Running lights and brake lights function!

[PPG9944]

It's been a while.  Life happens.  Minor update though.  I got it to start!

The start button engages whether the kill switch is in the on or off position.  Anyone have any idea what I did wrong.

The red and yellow wire runs to the start button directly from the battery.  The red and green wire goes out from that into the clutch switch.

The common power runs into the kill switch and runs out into the black and white wires which hooks into the coils

Any ideas?

[calj737]

That's normal. It's the BLK/WHT wire that runs it of the RUN button to the coils (delivering 12v) that is effected by the KILL/RUN position. START will spin the solenoid as long as you have 12v in the battery 

[Restoration Fan]

That's normal. It's the BLK/WHT wire that runs it of the RUN button to the coils (delivering 12v) that is effected by the KILL/RUN position. START will spin the solenoid as long as you have 12v in the battery 

What he said.  The start button should go whenever you press it.  However, the engine should not run (ie no spark) unless the kill switch is in the run position.  Instead, you'll just hear it turning over & over without firing.

[SOHC4 Cafe Racer Fan]

This is also a good way to check oil flow before the first firing of the motor (running the start button with the kill switch on).

[PPG9944]

You guys are brilliant!  Thank you!  I definitely did not even consider that as an option.  I just checked real quick and the kill switch does indeed kill spark when in the off position.  I'm used to my shadow where the starter won't crank when the kill switch is off.

[PPG9944]

Here it is in the current state.  I was messing around with it with my buddy the other day.  Gotta replace the clutch plates, shorten all the cables and sadly going to wind up pulling the motor again.

When I bought it, the front left cylinder was the one that was seized up.  We found some new marks on that cylinder bore and also, that side gets super hot super fast while the right side of the motor stays nice and cool.  When I got it, I didn't open up the bottom end but at this point if the motor is going to be out again to see what's going on, might as well open the bottom to see what's happening and replace the crank and rod bearings.  Sad day but I want to be able to ride this bastard. 

[PPG9944]

IT RUNS!!

Got to ride it for the first time this past Sunday.   Having a problem with the fuel flow though.  It seems like it creates a vacuum somewhere as i cannot get the fuel to flow through the filter down into the carburetors properly.