HPI Install RD

[SUPERTUNE]

On the HPI, I would do the charge coil mod as Mark said, disconnect the charge coil ground and connect to a new wire lead to run out to REC/REG as a 2nd charge leg. I think they come too close to being enough charging as they come out of the box with only a single charge wire setup.
Chuck

Can you point me to where the mod was talked about?

All I think you have to do is un-ground the charge coil lead on the backside of the stator and connect a new wire lead to run up with the rest of the wires and use it a for a 2nd input lead at the rec/reg so you now have 2 ac wave leads instead of 1 like I did on Mikes setup.

If you see in this pic 2 leads off the rec/reg are tied together as a purple and a yellow then connected to the single yellow lead the HPI came with.
Now that you just ran a 2nd lead, now unsplit the tied in purple wire and connect to the new lead you just made and now you have 2 ac leads into the rec/reg. Simple I think...
DC diagram on the left is the one your looking at.
Chuck

[m in sc]

THAT IS CORRECT

[CASADEHUSKER]

Guys see if I have this right.  I am not so good at electrical.

Unground stator......So disconnect 4th winding from the ground and run and new wire up the harness.  This new wire will connect to Purple wire from R/R (reference above pic from Chuck, the R/R from HPI)

Yellow wire from stator to yellow wire on HPI R/R.

Red wire from R/R to battery.

Black from R/R to frame ground.

CDI orange to Coil.

CDI and Coil grounds to Frame.

CDI black/white...?


Orange and gray wiring harness (previously connected to coils) no longer used.

Red and white wire from harness....no longer used?

Thanks, just want to make sure I get this right.

[SUPERTUNE]

Guys see if I have this right.  I am not so good at electrical.

Unground stator......So disconnect 4th winding from the ground and run and new wire up the harness.  This new wire will connect to Purple wire from R/R (reference above pic from Chuck, the R/R from HPI) YES

Yellow wire from stator to yellow wire on HPI R/R. YES

Red wire from R/R to battery. YES, connect on positive post with the stock red fused 12v wire.

Black from R/R to frame ground. YES, and make a jumper eyelet wire from frame ground point and to case bolt on engine for added engine ground. I also make a 2nd eyelet wire from frame ground connection to the negative post

CDI orange to Coil. YES, stator harness plugs into cdi unit

CDI and Coil grounds to Frame. YES

CDI black/white...? To be used as a kill wire for coil, connect to a toggle switch then to frame ground connection or kill button that then goes to frame ground connection for closed to ground for engine kill. Like a dirtbike button. You can also wire in a bosch 5 pin relay to run on the stock ignition switch.


Orange and gray wiring harness (previously connected to coils) no longer used. Not used

Red and white wire from harness....no longer used? That is the 12v hot with the stock key to power dc battery coils. Not used with toggle for kill or button for kill. Will be used if you install a bosch 5 pin relay like the Powerdynomo/Vape cdi does.

Thanks, just want to make sure I get this right.

Answers in BLACK

Chuck

[SUPERTUNE]

Powerdydnomo/Vape wiring PDF

https://photos.imageevent.com/supertune/paulsrd400//icons/72xr102.pdf.jpg




Look at the 5 pin relay and the Vape coil kill wire is bl (blue on the coil)
Its a black with white stripe on the HPI, but will wire up the same.

PD/Vape diagram is in Euro wire colors on the relay...
br (brown) is ground, You can do them in black to frame ground connection.
The sw (black) wound be the 12v red w/white stripe coil wire from the harness where the old coils were fed with 12v, now will go to the relay for 12v power switching.
Just connect to the proper terminal #'s on the relay as shown.

I'll try to explain more later, as it's way, way past my bedtime...
Chuck

[CASADEHUSKER]

I appreciate the guidance.

Thank you

[CASADEHUSKER]

So do we have to do a separate kill switch or can we just wire into the stock On/Off switch on the bars.

Not sure it will matter but I should have told you I am working on a 1978 RD400.

[Czakky]

You wire in a relay to the normally closed contact to the ignition/kill switch. A magneto is grounded to kill it. You can wire it however you want either kill switch or ignition switch.

[SUPERTUNE]

So do we have to do a separate kill switch or can we just wire into the stock On/Off switch on the bars.

Not sure it will matter but I should have told you I am working on a 1978 RD400.

OH Poo, you missed my point! I need to get better....

Re-Read what I said....I added relay.

Red and white wire from harness....no longer used? That is the 12v hot with the stock key to power dc battery coils. Not used with toggle for kill or button for kill. RELAY Will be used if you install a bosch 5 pin relay like the Powerdynomo/Vape cdi does.

Also I should have said...if wanting to use the stock wiring and ignition key setup...to use a relay wired in as I showed.
Sorry...

Chuck

[CASADEHUSKER]

No, you did great Chuck.

Was probably past my bedtime also and I missed the RELAY.

Thanks

[turtle]

hey chuck should I update my wiring for better charging or leave it alone.

[1976RD400C]

I've had my HPI up and running on my RD400 for 4 years now. It has performed perfect.

[Czakky]

Anybody know the thread pitch of the crank bolt that holds the rotor?

My bolt is too long and not threaded enough to just cut it down.

[SUPERTUNE]

7mm x 1 is the RD crank Mag side threads.

Some Ace hardware has them, no lowes or home depot.

I buy all my Metric hardware here...

https://www.belmetric.com/
C

[SUPERTUNE]

hey chuck should I update my wiring for better charging or leave it alone.

If your not having the battery run down too much, just leave it. If your going to add more lighting or more power drawing items like more lighting, a phone charger, then yes.
Your bike is pretty light on battery load, so that's a good thing.

You will have to pull ignition stator out, then retime as well to do this mod.
Chuck