[81honda]

Im still having trouble getting my bike to start. I thinks its a bad wire but I just cant find it. There are a few splices in the wiring harness that I think are from a previous owner, maybe not I dont know. Would it be more work to try to build a new harness (All the ones online look just as rough as mine) or should I keep digging to find the problem? I would rather not take it to a shop I prefer to spend a little more time to figure it out myself. Is a rebuild as hard as it looks. Its an 81 Honda Cm400e

 

[DianneB]

Keep troubleshooting!

Building a wire harness is a hellofa job, particularly connectors, and it takes a whole lot of spools of wire to have all the different colours and stripes in the different gauges. If you don't stick to original colour codes, it is going to be nearly impossible to troubleshoot in the future.

 

[cmonSTART]

Ya, I would keep the stock harness if at all possible. If you really have to, just piggyback a wire or two to correct some defect. Been there.

 

[wadenelson]

I suggest you start by A) downloading a wiring diagram of the harness that is supposed to be on this bike B) create a wiring diagram of what is actually connected to what on the bike, individually tracing, following each wire or using a meter to check continuity between each end, C) correct any discrepancies, add any "detour" wiring needed, etc. You can find by searching "wiring diagram" in this site several posts leading to sites where you can download virtually any wiring diagram for any bike. Or buy a manual online (ebay) containing a wiring diagram. Make this your winter project. Or you can pay a professional to debug why your bike won't start andhe'll fix the 1-3 wires that are the actual problem and be done in 3-4 hours.

 

[wadenelson]

IF you do build /purchase a replacement harness, be sure to add blinker fluid to the turn signal circuits before you use them the first time. Otherwise they may fry the first time you signal a turn.

 

[slumlord]

Knowing what connects to what

http://www.satanicmechanic.org/wiringcodes.shtml

This chart will aid you greatly if you take the time to really study and understand it.

You can also verify the bike will start by just hooking up a few components. Have you ever heard the engine fire up, or at least run a few beats? There are shortcuts to get you there as well.

I does pay to clean all those male/female connectors throughout the wiring harness. A .177 bore brush for a pellet gun is handy for the female connectors. Use dielectric grease on them to cut down on future corrosion.

 

[81honda]

If it touch the starter wire to the battery, the bike fire rights up and runs really well. I have a new solenoid, new battery, when hit the starter button the solenoid just clicks.

 

[wadenelson]

Do a search on this site for "voltage drop"

 

[slumlord]

voltage drop reference http://www.motorcycleforum.com/showthread.php?t=151506

Also a good price for a new keyswitch if your testing indicates a problem

http://www.partsnmore.com/parts/honda/cm400e/?filters[fitting]=custom

Good job on doing the work around to bypass the defective components. My best guess is a solenoid or an ignition switch or perhaps it is just a connection that involves one of them. Do not overlook battery connections, the grounds or where the grounds connect to the bike.

Voltage drop testing works [from personal experience]

 

[wadenelson]

Sorry, THIS is the link I should have given you for a no crank

http://www.motorcycleforum.com/showthread.php?t=156258&highlight=diagnosing

 

[slumlord]

Hey,Wade, why don't you drag and drop the no-crank as a link to the voltage drop thread? It is your stuff, so you should be the one to do it...

Easy way to add it to a stickied thread so we do not lose track of it.

 

[yahmyxs]

to be sure, your solenoid also might be failing

you need to check for loose connections, make sure all your direct battery connections are clean, and make sure all the connections to the solenoid are well contacted.
Your starter button maybe failing. Or your kill switch might be failing.
please don't pull the entire wiring harness... you need some dedicated training of some type to tackle that one!

 

[81honda]

The wiring harness is was all taped up so i pulled most of it off. THere are about 7 of these splices. are these factory or did someone else do these. if so does it tell me anything.

 

[DianneB]

The wiring harness is was all taped up so i pulled most of it off. THere are about 7 of these splices. are these factory or did someone else do these. if so does it tell me anything.

That isn't factory so somebody has been messing with the wiring. Gawd only knows what problems they may have created.

 

[Critter]

The blue wire is a total mess

 

[81honda]

got the bike to start...turns out the new solenoid i bought was no good. but I still this mess of wires...should i bother with them or leave it be till it causes problems

 

[DianneB]

Tape up the joints and leave them. Aside from being sloppy, they are electrically solid and shouldn't cause any problem.