1973 CL350 Restore - First Timer!

[ancientdad]

Got my new dyna coils fitted and installed my Charlie's Place electronic ignition. Anyone have any good sources for how to route a custom wiring harness on a 350 and also how much slack to leave in the headlight bucket? I need to cut some extra length and am a bit nervous about cutting off too much.

Good to see you back Mike. I've never installed a Charlie's ignition, but are you sure the backing plate is oriented correctly? The cutouts look like it should be rotated left about 90° but if you followed instructions then I suppose that's how it's intended. Also, the index mark on the left exhaust adjustment shaft is pointing the wrong way, should point out away from the camshaft like your left intake does.

 

[mikemill]

Good to see you back Mike.

Good to be back!

I've never installed a Charlie's ignition, but are you sure the backing plate is oriented correctly?

Yeah, pretty sure! It looks like the photo in the instructions.

Also, the index mark on the left exhaust adjustment shaft is pointing the wrong way

Good eye! Ill get that corrected.

So my plan for wiring this B* is to start at the front with the headlight bucket connections and work my way toward the back of the bike. That should allow me to cut the harness length as needed to reach my battery box appropriately. But how much slack do I want in the bucket to ensure the bars turn freely without causing excess bulk?

Also any tips on routing a custom harness? Where are the main points I should zip-tie it?

 

[ancientdad]

Typically the stock harness has about a 2" to 3" droop as it comes out from under the tank and goes past the steering head into the headlight case. If you're using the stock handlebar switches (can't recall) then compare the length of those wires inside the headlight case to give you an idea of how long the main harness wiring should be there as well. Obviously, the important thing is to have enough length to work with without taking up too much space in the headlight case for the headlight once put back on.

 

[MechE_13]

Dude, I’ve been scrolling back through the history and everything is looking great. Keep it up! That bike is going to be sexy.

 

[mikemill]

This weekend I modified my battery box to allow for routing some wires I hadn't planned properly for before. Stuff like the battery ground strap, starter motor cable, and reg/rec cords. I dremelled out a space for these in between the two holes I originally had and then inserted a piece of grommet to protect the wires being routed there.

Then I put my big boy pants on and actually started modifying wires to set up the battery box. Scary! I was cutting wires down to size, stripping a piece, adding the correct connector (ferrule for m-unit) and adding a piece of heat shrink for a secure connection.

My ignition was a little trickier because one wire has to go into the m-unit and the gauge is WAY too low. So I cut it down, added a bullet connector and heat shrink. Then I took a piece of high-gauge wire (18 or 20 ga) and added the female side of the bullet. This didn't crimp down securely enough due to the wire gauge, so I also added some solder for a secure electrical connection.

 

[mikemill]

I made more progress tonight in battery box land. It was just more of cutting wires to length and putting secure connections on them with proper terminals and heat shrink. I also removed the paint around the lower rear engine bolt for a nice clean connection when I eventually connect the battery ground strap.

I have one question about the solenoid, however. Now that I have it in my hand, how do I know which post should be connected to the battery and which should be connected to the starter motor?

 

[LongDistanceRider]

The left terminal in the picture shows a secondary eyelet which I would think is for power from the battery to the M-unit. The right side doesn't have that so I would guess it's the starter connection.

 

[Yendor]

I think AD is correct on the Plate for the Charlies Place is 90 Deg too far clockwise.
I have (2) of these running and both have the pickups at the 6:00 position.

 

[66Sprint]

LDR is correct.......

 

[mikemill]

Sweet!

Unfortunately I have now discovered that my starter motor cable is too short haha. I need to make a new one. In order to make it as bendy as possible and easy to squeeze into the back of my battery box, what is the minimum wire gauge I can use for this?

 

[ancientdad]

First, are you routing it behind the starter motor between the starter and the crankcase? That's the factory routing and it might save a little bit of length, but if your solenoid in the new electrics tray is far from where it was originally that little bit might not help. I'm thinking the starter cable is at least 8 to 10 gauge

 

[LongDistanceRider]

The starter cable measures between 4 and 6 gauge, I think it was a JIS measurement standard that doesn't quite hit the AWG numbers.

 

[mikemill]

Hi guys, I'm wondering what one of the wires are for on the 1973 CL350 tachometer. Below is a list of all the wires and their colors. I also filled in the ones I think I know the functions of. Really wondering what the black is for!

Blue - power for left turn indicator
Orange - power for right turn indicator
Green/red - power for neutral light
Green - Ground
Brown/white - power for backlight
Black - ???

I'm connecting up everything in the headlight bucket, and it's unfortunately been a LONG time since I've had my hands on this project so I'm second-guessing myself about the tachometer wiring (my diagram shows 5 wires but the instrument has 6).

Thanks in advance!

edit: Could the black wire be power for the neutral light?

 

[LongDistanceRider]

Yes, Black is the power wire for the neutral light.

 

[ancientdad]

edit: Could the black wire be power for the neutral light?

Yes, for the neutral light and every other key-on function as well.

Good to see you back Mike.

 

[mikemill]

Yes, for the neutral light and every other key-on function as well.

Good to see you back Mike.

Thanks Tom! This time I'm staying back and finishing this bike!

Another stumper -- I have those universal brake light switches (like this one). Which wire is ground and which is power?

 

[ancientdad]

Thanks Tom! This time I'm staying back and finishing this bike!

Another stumper -- I have those universal brake light switches (like this one). Which wire is ground and which is power?

Please tell me you didn't give them $20 for that switch.

Neither wire is ground, one gets power from the Black switched power wiring and the other (Green with Yellow) sends it to the brake light.

 

[mikemill]

Please tell me you didn't give them $20 for that switch.

Nah, the link was just handy to demonstrate what I was talking about.

Neither wire is ground, one gets power from the Black switched power wiring and the other (Green with Yellow) sends it to the brake light.

Awesome. I actually do need to route one of the wires to ground just because of how the m-unit is wired -- I just wasn't sure if it mattered which one I use or if power flows through the switch both directions (I'm assuming it does). I wired black to the brake input terminal on the m-unit and green w/ yellow stripe to ground.

When that circuit is grounded via the switch, the m-unit sends power out of the brake - output terminal to the brake light.

 

[ancientdad]

When that circuit is grounded via the switch, the m-unit sends power out of the brake - output terminal to the brake light.

I guess I get it (I mean, I do understand the circuit design) but the m-unit still seems like reinventing the working wiring harness. I suppose if you're using different handlebar switches then it might "require" the use of one but even then it could be re-wired to work with a ground instead of power, pretty much anything on the bike could. Glad you have it figured out though.