1973 Honda CB750 Custom Build Part 32 - Final wiring

time to finish up the wiring in the cb750 welcome to hack a week well it's time to get the wiring wrapped up on this project and we've got quite a few things to tackle today we've got to get the spark plug wires connected to the coils put the spark plug wire ends up get those back on the plugs I'm going to route the rest of this wire harness up into the headlight bucket which is a very intimidating thing for a lot of people when they pull the headlight by the motorcycle and look in there at that rat's nest and it just kind of freaks people out they don't know where to start but you know what you take one wire at a time and work on it that way and what you know the wiring system on Honda bikes and the colours they tend to be the same throughout all the years the greens are always your ground wires so always make sure those are connected like signal lights have a tendency for the wires to come apart in here and all that so we're going to get those connected we are going to finish connecting up the alternator neutral switch the ignition wires from the points need to be routed over here and connected I've got to repair the harness that connects to the alternators got a little break in it here the one that runs down to the neutral switch then the wires need to be routed toward the back for the signal lights back there I'm going to put the signal lights on just yet but the wires just hang there so that's not a big deal it's just a few wires that plug in so where do we start today well I think we should start reviewing the coils and get spark plug wires on then we'll move on to that crazy headlight area these are the spark plug wires that came with the Dyna coils they are a copper core wire so that's a solid copper core in there these are the NGK ends that were on the other wires they're not from the factory those are added on and these aren't too difficult to install they have a threaded end in there it looks kind of like a wood screw it's just this brass threaded section and it screws right on to the end of the spark plug wire so we'll put this boot back in place for now and the first thing we've got to do is cut off these ends that came with these wires we're just going to snip them right off we got plenty of wire to work with here so we'll just cut all four off and I'm going to take a little bit of the dielectric grease that I use on a lot of stuff and put a little bit of that on the rubber boot that's on the spark plug wire and put a tiny bit of it inside there what that will do is help me to push that wire down in there a whole lot easier and it's just about this simple you just start screwing them on and they will kind of bottom out and start to feel a little resistance right there there we go that's as simple as that so we're going to do that to all four ends all four ends are in place and now we're just going to shake all of these wires cut them in half we're going to take them over to the bike and figure out how long each one of them needs to be when I worked on the coils the last time I labeled this coil two and three so I remember which was which so this is the one that's on cylinders 2 and 3 which are the two Center ones and I just simply need to figure out how much wire I need leave myself a little bit of room to be able to pull it out and put the thing off to the side so the connections are on the bottom of these coils they come out this way and there's a special end that we need to crimp on to the wire so let's see let's just hold it right about there I guess and we're going to clip that one and then this is the one that goes over well you know what let's just make them both the same length here's one of the spark plug wire ends that go on there just a conventional type and there is a tool to crimp these on to spark plug wires I don't have that tool I have another crimp tool that'll probably work okay though so what we've got to do first is strip back a little bit of the wire on this plug wire I'm just going to take a pair of wire strippers and I'm using the 12 gauge stripper section and I'm just going to strip away about a 13 millimeter piece there 13 or 14 millimeters so we've got bare wire hanging out we're going to take that wire just give it a little get that little other reinforcement thread out of the way give it a little twist and we're going to bend it over like that now that it's bent over we'll take the end and place it on there in such a way where that bent over piece is on the bottom side of the crimp so let's take the crimping tool we're going to give this a little squeeze that's good enough that'll work and we're going to put that into the coil so do the same thing the other one and repeat that on all four wires there's a boot that goes on the end of these probably should have put that on first a little dielectric grease in there and I can slide it past this crimp done and easy enough let's try to get this in a position where you can see what's going on we're just going to push these in they just kind of click in place I had a question about this wire right here this comes from the points and I didn't know where it out 'add so I got on the single overhead cam for forum otherwise known as the stock for forum and I posed the question there on the thread and a couple of guys answered for me uh ray V and art from Bama thanks for the input guys you guys get a shout out they mentioned where this stuff routes and goes and ray V told me first and then art from Bama posted some pictures and it turns out they're supposed to be a little clip right here on this bolt the one that I've taken out of the case I can't take it out of the case now though and I didn't put the bolt on so what I've done is I've taken my little Clippy thing and I've split it I can put it over that and let's see which way should that go up or down probably like this okay so if I can just put it over it and then I can just take the needle nose pliers bend to that little part that I split back and then I can just put that sucker right back in there ah little tricky to get in there okay there we go get the wire into the clip i rerouted it I had it one way but I'm gonna put it a little different here go ahead and just bend that up so the little clip is holding it in place now and then we're going to route it behind the oil lines here and then I'll grab it right here and pull it up through and then it goes over to another clip now it comes up through here and there should be a clip on that bolt so let's pull that off and we're going to put this clip on pretty sure this is the one this looks like the one in the picture that art from Bama posted it's a pretty large clip I'm not sure if it holds other wires or not but anyway we're going to put it on there because I had it in the parts bin 9 foot-pounds just like all the other six millimeter bolts okay the clips installed and now we can connect things to this section of the wiring harness the blue yellow black and green or the yellow stripe so the ignition wires go to here blue the blue yellow to yellow and make sure that they're pushed all the way inside the insulating plastic I like to push them in there with a little bit of help from a needlenose pliers and the brake lights which connects up here let's see we get the green I'm at the yellow stripe ah make sure that's in all the way and then we have a black one let's push that in with the needlenose also click that's it's all the way in now we can take all of this and tuck it down in here into that clip put all the wires in there bend it over there we go break light switch hand ignition are all set let's move to the other side of the bike there's three yellow wires to connect those are the ones coming off the alternator it doesn't matter which ones go where as long as the three yellow ones go to the three yellow wires make sure they connect good and solid these tend to get a little hot you can see that on these older ones they're a little discolored that's from heat this wire goes to the neutral switch we'll just drop that down here for now and right here we have a blue one with a red stripe that runs over there to the oil pressure switch that wire runs through the box that houses the starter so let's push that in that went click now tuck down in here there's two more that come from the alternator or a green one and a white one there's the green wire they're pretty short I'm going to hang on to these with the needlenose pliers make it a little easier click and the white wire and to click and all of that stuff will route underneath the cover here that covers over the sprocket but for right now we'll just leave that alone and we'll get down under the engine here and connect up a neutral switch neutral switch is right there it's got a screw in it pull that screw out and let's get back connect it up now I've seen a couple pictures where there's a little retainer clip down here somewhere - saw one where it was on the oil pan but I don't see where I can actually have the slack to do that I'll have to check into that one it might go over there somewhere but we can come back to that later all right back up to the top this whole mess right here we're going to shove up above the frame put that out of the way and we've got three wires right here to connect to the voltage regulator green white and black and there's a little sticker right there tells you right where they go green is the upper one white one goes in the middle and the black one on the bottom now we've got the starter wire that's this big black when it comes up here and that makes its way up here to the starter solenoid so that's going to go on this side of the starter solenoid tighten up that ten millimeter bolt there was probably a insulator over that at one time don't have one here on the bike at the moment but we'll leave it like that for now we're ready to drop a battery in here now I'm not going to hook up the terminals just yet but let's drop one in there I picked up a AGM battery so we got a couple more things to connect here let's see this is going to go to the positive side this one right here this one goes nowhere as far as I can tell extra red wire that's on the hot side of the starter solenoid on the main harness we have one that's red with a white stripe and that's going to go on to this wire right here which is a red one with a white stripe okay that's connected up and let's see this green one I have to check where the green one goes I think that that's a main ground wire that would go probably on the chassis somewhere it may go over right directly on to the battery cable I kind of there's a battery post I'm not sure how to look that one out but anyway that's a green wire that's going to go to ground the rest of these all run back to the taillight so the ground wire would be the next one the big ground cable just a minute ago I found the boot that goes over that the starter cable so that's good I got that taken care of now the ground cable let's see that'll come up through here and connect to the ground on the battery right there and the best I can tell is it goes to this bolt right here that holds the engine in I've found a few pictures online that show that that's where it goes there's a clamp it holds it around this part of the frame right here so I need to take that nut back off the nut is removed I push the bolt back and I'm actually going to file some of the powder coat off from this section of the frame that way when I put this on I will have a good ground not only on the engines from the bolt but also right to the frame itself so let's see a little smear of dielectric grease on there just to slow down any corrosion that might happen we'll get the cable in place here all the washers back on and we'll tighten this bolt back up and that will take care of the ground connection okay I've routed the wire harness down under here so that everything that's going to lead to the back taillights is now tucked under here this green ground wire goes right here on this lug and a six millimeter bolt goes in there what that holds on is the seat hold down latch it's got a key in it and there's a thing that pokes in there and the seat catches on it and you can lock it now in this one it's different key than my ignition switch but at least I have a key for it so we'll put this on this goes through here there's a peg up on the top that locates it and I know you can't really see that I'm tightening it now but that's the bolt that grounds out the wire harness right there you can see that a little better now tightening it up with a wrench here okay that's good to go there's a fender liner here that goes down in there these two little clips hold the wire harness so since I'm working on the wire harness see if we can get this in there come on you can do it okay that's that's one side and now let's see if we can get this side pushed Janet yes there goes that wasn't so bad after all all right up next we've got the handlebar controls the switches and the wire harnesses that go from those to the headlight bucket where everything joins together the stock handlebars had holes in the handlebars where they went through and then they came out here somewhere this set they have actually have notches in them some holes in them where the harness can come out I guess they're from a later year bike this side has of two the ones that I bought used that have good switches don't have those notches in them so I guess what I'm going to do is take all the guts out of this switches and everything else transfer it over to mine same thing with this side and we'll hook it all up that way got the left control mounted and they took the ones I bought ground out this section down below with a die grinder so that the wire can come out of it run outside the handlebar and I painted it with black caliper paint and then touched up the letters by hand with a tiny little brush looks pretty sweet so before we connect all this stuff up probably be a good idea to test out the switches okay so testing I've got the voltmeter here I'm going to lay this down here I've got it set on continuity testing so when there's continuity it makes a beep got the wiring diagram here and on these switches one at a time I'm going to look the wiring figure out what switch is supposed to connect to what when it's in a certain position and test it for continuity all right we're connected up to the brown wire with a red stripe that's the common for the high-low switch for the headlight the white wire is for the low beam so when I flick it to low beam yes got continuity okay same connection Brown with the red stripe is the common the blue wire should be the high beam yes that works horn button is the light green wire and what we're doing there is connecting it to ground so let's see let's just try touching it to the handlebars so that works signal lights which gets a little weird to test out but I can do a quick check here if I go to the center I've got continuity and then over on left I've got continuity between the brown with a white stripe and the blue with a white stripe and then when I go to the orange wire I should get a beep to the right nothing to the left or yeah middle and right I get a beep to the left I don't so there's a couple other wires to test but that pretty much tells me if that switch is okay so that takes care of this side now here's where you're going to see why all those wires end up in the headlight bucket because the headlight bucket is kind of like your brain that's where all the wires go all the nerves go it's the nerve center so we're going to take the main wire loom here we're going to run it through that hole in the back start my loops till we get that pulled up into there okay so there's those wires now what we're going to do is take what was coming off from that left-hand control switch we're going to run that between the forks and right through the same hole bring all that up into the headlight bucket now all of this stuff is going to connect together in a while but next we got to get the right hand switch connected but the other switch all refurbished and installed test it out on the bench everything is working and we're going to take this pigtail here and run it up into the headlight bucket just like the other one through here all right we've got the left and right control switches and we've got the main harness here there's the indicator lights for the turn oil neutral and high low beam and we do get that old harness pulled up engine all right that's I believe everything that's got to come into the headlights bucket now there are two more little harnesses I did not install yet this one is for the instruments for the speedo and the tach I don't have that one in there I suppose I could just run it in there and connect it later same thing with the front brake light switch so we can bring those in this one I can actually just push through here pull it backwards suppose that would work too so there's the front brake light switch that's my left control this is the instruments just two wires we'll go ahead and pull those through okay now what it is is just a matter of matching up colors really that's all there is to it and so what I usually do is get these all untangled get them all laid out nice and clean and the first thing I want to do is find all the grounds all the green wires start with the grounds first so we get all the green wires grouped together let's see there are dark green by the way there are three of them you'll see a lot of these have double and quadruple connectors on them these have places for four wires to go into this one has places for two wires to go into usually there would be a wire connected here there would be like a a round slug of metal with a green wire coming out from it that's to help ground out the chassis here of the signal lights for right now I'm just going to wire it up without those I will probably make some myself later because what I've done here since I have those custom billet aluminum headlight brackets I just took the signal lights and use those as the mount for the headlight bucket normally these would mount down here further and there would be some bolts that would go through here and hold this to the to the brackets but I did it this way so back to the wires so we got the green ground wires so now we want to do is take anything on these other harnesses that is green and connect them up so we just get all that crap out of the way and pull these through here are there any grounds on that one no there's not there is definitely one right there so let's push that in and connect it up that's one for the instruments here's a green wire here that one's for the brake light switch plug that one in there and like I said there would be a couple that go here take up a couple spaces let's see what else we got Wade down here goes to the horn horn switch and that would be over on the left side control here's the wire for that and there is the brown with a white stripe and now we'll connect that one in here and I believe that takes care of that and so you get the idea I'm not going to bore you with 20 minutes of video of me connecting every single wire you get the idea here what you've got to do is really pay attention to these connectors right here because they will tell you what's going on with this stuff here for instance here's here's a blue one it's got a little white tag on it if you look on here enough you're going to find that right there is one that's got one two three four wires on it that's a blue connector now that one would be this guy right here that's the one that goes to the signal light anyway step at a time just keep plugging away and you'll get them all connected I got most of it connected up there's a few leftovers going on here but we'll figure it all out so I'm about to finish up at the rear I've got the taillights on there temporarily mounted not really bolted yet but I'm going to connect up these wires then we'll connect up the battery get some fuses in there and see what works and what doesn't okay this is pretty straightforward just Orange - orange and the green is around the green the ground that's about it I don't have the stoplight down there we'll get to that later okay I got some fuses in there key switch on all right I got some lights I got the instrument lights I got a neutral switch light don't have the high beam yet because I don't have the connector up front for the headlights and that's integral to all of this working signal lights don't work because I don't have the flasher unit installed we do have a starter what else I don't have the horn connected I can go back here and test the brake light switch so let's see no voltage right now at the brake light I let go of the switch for the front I got eleven point three volts and I'll push that switch back in let's pull on the switch for the rear brake hard to pull on yep I got voltage there too so those are working okay I just connected up the horn and that kind of kind of works that horns a little lame I got a couple to choose from but I got a horn so well that's that's a pretty damn good start well not a bad start everything that I've connected up is working I've just got to get a head light fixture in here that little three-pronged plug I got to buy one of those and probably it will have all the connectors on it'll take care of the rest of this other stuff and I did notice that off from the signal light switch on the wiring diagram it does show that there was a double filament bulb in these these have just a single so this may have come from a different year for all I know it could be that was off from a later model that had that but anyway I can just eliminate those wires I don't need them so let's see what's next get that straightened out and I think we can probably start putting more things in the blank get the powertrain hooked up get the front sprocket on that chain on there and the chain guard and then we're going to move on to what brakes front brakes the rear linkage has to be connected up but that's all in future videos but this pretty much takes care of the electrical system and like I mentioned earlier don't let it intimidate you just take your time use the wiring diagram use a continuity tester to test from the back to the front to find the wire you want and make sure you get things connected up right the worst that will happen is you'll blow some fuses so keep a few extra fuses on hand as you're doing this and take your time you will get there and you'll be able to figure it out I know when you look in there I mean God look at it it looks like just oh my god where do all those wires go but you will be able to figure out trust me patience is what it takes well thanks for watching and thanks for the 10 million views that I just hid the other day on the YouTube channel here whoa hack a week is cruising right along and we're going to keep on going we'll keep trucking with the cb750 got some really neat electronics projects coming up to Raspberry Pi I'm going to put a Windows 10 internet-of-things operating system on that play around but hoping to get this thing done by maybe the end of April something like that there's a few bike shows I'd love to take it to so thanks for watching thanks for sharing thanks for all the donations and until next time and then into that threaded section there and whoops we'll go this way wait a minute where am I okay

Channel: HackaweekTV

Views: 56,397

Rating: 4.9621301 out of 5

Keywords: electronics, diy, hardware hacking, hackaweek, motorcycles, circuit, automobile, mechanical, cb750k3, cb750, cafe racer, honda, wiring, turn signal switch, coils, ignition switch, headlight wiring, tail light wiring, battery, brake light, brake switch, head light switch, horn switch, starter switch

Id: r3g3KQ-h80I

Length: 31min 48sec (1908 seconds)

Published: Sun Mar 06 2016