Author Topic: CB 750 Project 1 - Rides Well but a few tweaks needed (Read 116533 times)

timbo750 · « **Reply #550 on:** February 21, 2016, 12:15:06 AM »

Terry. Challenge accepted.

Terry in Australia · « **Reply #551 on:** February 21, 2016, 12:29:44 AM »

OK, set the stop watch mate, any longer than 30 minutes and you'll have to apologise to Sean, his memories of installing that fcuker are very similar to mine!

timbo750 · « **Reply #552 on:** February 21, 2016, 12:59:42 AM »

Done. I couldn't find the original pin. May of been so bad I threw it out. Used a 6mm stainless long shank bolt and cut it down then drilled a 3mm hole. It most certainly would of been easier without the oil tank, and engine in place. I still need to fold over the split pin ends but need another pair og long noae pliers and I have them at work.

timbo750 · « **Reply #553 on:** February 22, 2016, 01:53:40 AM »

Next thing I am trying to sort out are the wires behind the headlight. I have no worries reading and understanding a wiring diagram, and in fact I could rewire the entire bike if I needed to but I certainly do not feel the need.

What has me a little puzzled is that it would seem I have extra wires. I have looked over the different diagrams for later models as cross reference but the changes really were only minor and don't answer my questions. most of the wires connect up alright but the following wires need sorting.

From the L/H switch, I have 2 pale blue wires, one is slightly different in color but the wiring diagram has 10 wires and I have 11.

From the main Harness, the following wires seem to be extra.
Pale Green
Brown
2nd Brown w/white stripe
2nd Black - have checked polarity, it is connected to the other black wire
Grey

The main Harness is new and I got it a long time ago from ebay and supposed to be K3 but the Clymer manual has K1-K5 all the same, I believe only a few plugs changed. The switch blocks are also new and I got them from Z1 Parts.

I am tempted to connect everything else and to start turning things on to what turns live, but if anyone has any bright ideas I would appreciate some feedback.

Terry in Australia · « **Reply #554 on:** February 22, 2016, 02:21:35 AM »

Don't worry about it Tim, some switch-blocks look identical but probably originated from different Honda's over different years, and so there are usually extraneous wires that can't be accounted for, however, as long as you get all your ignition, lights, horn and blinkers working, it doesn't matter.

The K2 I'm building for Mike is a case in point. I couldn't get a K2 harness, so I bought one for a K3-K5 (or maybe K6, I can't remember) and it has way more wires than I need, but as Honda used pretty much the same color code for each bike of the era, I could still plug in the light blue and the orange wires from the left switchblock, which made both blinkers blink, the brown wire with the white stripe for the headlight switch, the black wire with the white stripe for ignition, etc.

I just use one of those little test lights with a clip on one wire and a point at the other, to earth the light, connect it to each wire coming up from the harness with the key switched to "on" and it only takes a few minutes to connect up all the wires I need, then I tape off any "live" male connectors so I don't get any shorts when I shove the headlight assembly back into the bucket. Simple.

timbo750 · « **Reply #555 on:** April 11, 2016, 02:01:57 AM »

Managed to get in to the shed after a long unwanted absence. Didn't really do anything except work out were I left things, the question I have for the brains trust out there is about the coil wiring.

I have fitted 5ohm dyna coils and didn't get much of an explanation of which terminal is for which plug. You will see from the photo that there are two screw terminals but i don't know which one is for which plug wire.

Terry in Australia · « **Reply #556 on:** April 11, 2016, 02:53:42 AM »

That's an easy one Tim, the reason they're not marked is because it doesn't matter. Cheers, Terry.

timbo750 · « **Reply #557 on:** April 12, 2016, 12:39:40 PM »

So each cylinder gets a spark on the compression and the exhaust stroke.

mystic_1 · « **Reply #558 on:** April 12, 2016, 03:09:39 PM »

Correct. "Wasted Spark Ignition".

mystic_1

timbo750 · « **Reply #559 on:** April 12, 2016, 08:17:00 PM »

I suppose it makes for simpler ignition and wiring but I have to admit that it had me thinking that dyna had let me down, not so it now seems. I will say though that the head scratching on this one has increased my bald spot.

timbo750 · « **Reply #560 on:** April 26, 2016, 01:55:35 AM »

Managed to get a bit more done. Started fixing the main cable loom to the frame, I test fitted an old tank to make sure nothing was rubbing and nothing catches. But now I need to find a 'Starter Motor Safety Unit' that connects to the red connector.

Terry in Australia · « **Reply #561 on:** April 26, 2016, 09:33:11 PM »

G'Day Tim, you, me and Cliff (Maduncle) all have the same wiring loom! Test to see if you have power to the coils before you go looking for the clutch lockout thingie, but if you don't, Scottly sent me a PM yonks ago about how to bypass it. Hey I finally scored a K0, so if you've still got that front hub, let me know what you want for it? Cheers, Terry.

timbo750 · « **Reply #562 on:** April 26, 2016, 10:49:27 PM »

Thanks terry. Still a few wires to hook up so will test then. Yes I do have the K0 hub and I think I found some other K0 part in a box but can't remember now what it was. Not sure what a K0 hub is worth Terry.

Terry in Australia · « **Reply #563 on:** April 27, 2016, 12:39:25 AM »

No worries mate, my standard offer for anything is 50 bucks, so you can decide if that's enough, or not. Cheers, Terry.

timbo750 · « **Reply #564 on:** April 27, 2016, 04:07:58 PM »

Terry, my first thoughts were 100 bucks so how about 75 and I will drop it off some time.

timbo750 · « **Reply #565 on:** April 27, 2016, 04:25:34 PM »

Terry, I am thinking I may have to bypass this safety unit thingy as the wiring harness is new and most likely correct. If you have that bypass info and could forward that would be great, I have tried to find a schematic for how they work internally but with no luck, if I had that I could wiring up a diode or relay to do the same.

timbo750 · « **Reply #566 on:** April 29, 2016, 08:35:43 PM »

Well I think I have sorted a solution to the safety unit. After studying the wiring diagram I have determined that I can do similar with a relay using the neutral switch to activate.

Turns out these things were never fitted to the Australian delivery bikes. I called into TT motorcycles in mornington on Thursday and he had never heard of it before.

maduncle · « **Reply #567 on:** April 30, 2016, 04:18:30 AM »

Quote from: timbo750 on April 29, 2016, 08:35:43 PM

Well I think I have sorted a solution to the safety unit. After studying the wiring diagram I have determined that I can do similar with a relay using the neutral switch to activate.

Turns out these things were never fitted to the Australian delivery bikes. I called into TT motorcycles in mornington on Thursday and he had never heard of it before.

Okay - so I am interested in what you are doing to deal with that unnecessary red terminal block - as I will need to do something too.

EDIT: oh look, this is on the forum in another thread.

"If you unplug the SSU and remove it you can by-pass it's function by jumping the solid Green wire to the Dark Green/Red wire( there is also a light green/red ). That's it, your done........the starter will now spin whether your in gear or N or clutch is pulled or not... N light will still work when in N 'tho..........."

I love this forum.

timbo750 · « **Reply #568 on:** April 30, 2016, 08:39:31 PM »

Yeah, I thought about that and I trust myself to clutch every time I start the bike but I would also like a safe guard. I have worked out a bypass and will post once I have a decent drawing done.

timbo750 · « **Reply #569 on:** April 30, 2016, 11:59:05 PM »

What I meant to say is that I have worked out a alternative. Here it is.

mystic_1 · « **Reply #570 on:** May 01, 2016, 08:20:21 AM »

Wow that's fairly brilliant. Nicely done!

mystic_1

Terry in Australia · « **Reply #571 on:** May 01, 2016, 08:38:16 PM »

Well done Timbo, that looks very professional. I didn't bypass the wires to the plug, but everything works as it should, except the kill switch. If the bike was mine I wouldn't care as I never use the kill switches on my bikes, but as it isn't mine, I might have to rethink it before I hand it over to Mike.

I'll take you up on the hub too mate, thanks for that, and I want any other K0 parts you might come across. Cheers, Terry.

timbo750 · « **Reply #572 on:** May 02, 2016, 12:02:20 AM »

Keep in mind guys I haven't tested it yet, however it is a very logic process so I can't see why it wouldn't work.

Terry I think the head is K0 but too keen on pulling that off the engine now.

Terry in Australia · « **Reply #573 on:** May 02, 2016, 01:37:02 AM »

No worries mate, if it ever does come off I've got a minty K2 head here that Cliff had hydro-blasted, and there are new bronze valve guides in a bag that I don't need as well. Cheers, Terry.

mystic_1 · « **Reply #574 on:** May 02, 2016, 06:30:41 AM »

Quote from: timbo750 on May 02, 2016, 12:02:20 AM

Keep in mind guys I haven't tested it yet, however it is a very logic process so I can't see why it wouldn't work.

No, I think you're really onto something here. Here's a thread from a while back where a few of us were kicking around the design of the SMSU:

http://forums.sohc4.net/index.php/topic,145726.msg1657876.html#msg1657876

Also in that thread are a couple of different bypass methods:

Quote from: Grinnin on March 07, 2015, 10:48:14 AM

I tested these this morning. They work. I.e. the starter solenoid responds to the starter button only if the clutch lever is pulled in or the transmission is in neutral.

Quote from: HondaMan on November 08, 2010, 08:11:40 PM

I'd quote you the page number if I had one of my books handy, but...

Find the Dark-Green/Red wire that went into the red connector that plugged into the safety module, pull it out of that connector and change the end to a male bullet, and plug it into the extra Green wire that is hanging near the rear of the battery box. Presto, it becomes a K0-K2! Just don't forget to pull in the clutch or find neutral before starting, or you'll make the DOT mad...

Do let us know your results, lots of people run into problems with this interlock circuit eventually.

mystic_1

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Author Topic: CB 750 Project 1 - Rides Well but a few tweaks needed (Read 116533 times)