1971 wiring diagram from scratch

pkaczmar

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Hello everyone.
Recently bought a 1971 XS.
This thing has been a racer for quite some time and has the bare minimum for electrical. no lights no ignition etc.... therefore i get to start from scratch. I'm looking to keep this thing Cafe style as it already has the tank and handle bars for it. Looking for a wiring diagram that includes headlight, taillight, signals and sticks with the kickstart but ads a turn key for power.
I know there are a number of diagrams but I can't sam to find exactly what i need or simply searching incorrectly.
I am a complete newb with electrical, would appreciate any help on the diagram.
And potentially some direction for parts?
Thanks
 
Welcome to the forum, pkaczmar.
To get you started, here's the wiring diagrams for the 1971 XS1B:

XS1B-Wiring.jpg


View attachment 22978
 
Thanks so much.
But as mentioned there is nothing left from the original wiring. I'm just looking for a simplified diagram that will work with the 1971, utilizing a kickstart.
 
Thanks so much.
But as mentioned there is nothing left from the original wiring. I'm just looking for a simplified diagram that will work with the 1971, utilizing a kickstart.

Hi pkaczmar and welcome.
FYI, that IS the simplified diagram, there's not one wire on it that the bike don't need.
If you think it's complicated, well, compared to the total of 7 wires (OK, 10 if you want signals) that work my BSA, it is.
Compared to my XS650 Heritage Special's 2-page electrical diagram and wrist-thick wiring loom, it's dead simple.
You say the bike needs ignition wiring? What's it got for sparks right now?
You could do worse than put your parts shopping list in this list's parts wanted forum.
 
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Whoa
i guess to a beginner at first glance this is rather overwhelming. But if you break it down I suppose it's not that bad and things such as neutral indicator turn signal indicator etc... you can easily cut out.
Currently wire runs from battery to the rectifier and to alternator and there is a single Ignition coil running to both plugs. The whole system is on a switch on and off. I just would like a turn key so you can't steal the bike.
And I suppose building this yourself would be the way to go? or does Mike'sXS sell this wiring harness? Also I suppose what rectifier and regulator and condensers would work with eachother? or are most simply interchangeable.
Thanks so much
 
Hi pkaczmar and whoa yerself!
If you have a single (presumably 2 wire) coil firing both plugs on a '71 XS650 it's ignition has been messed with and you'd best check what's there before ordering (it's the easiest way) a replacement wiring harness.
Take off the round covers on the ends of the camshaft to see what's in there.
The stock '71 (& up to '79) had points on one side and a mechanical advance mechanism on the other.
If there's nothing in either side but the ends of the camshaft most likely the ignition has been swapped for the '80 & newer Hall effect ignition.
If the bike runs, put your multi-meter on the battery to see if the alternator is charging (or even if it's still there)
Charging will show as a voltage jump from ~12V to ~14V at ~1,500 rpm and above.
There are other possible ignition mods, especially on a race bike, so check what's there before spending any money.
And take photos, I can't do those dancing signposts but a picture is worth a thousand words.
 
The 70 and 71 had the least complicated electrics. In 72 they added the e-start and had to add a few other things to make it work. The later models just got more so as the years went by.
If you want to buy a new harness Mike's lists one for the 70-71, XS1-XS1B bikes, $59. This isn't a bad price.
Making your own would run about the same. It has all the right connections to use all the stock parts.
On the pics good ones of what's under the round chrome covers on each side of the head. Behind the round cover that says Yamaha on it on the lower right side of the engine.
Leo
 
I took the round covers off the cam shaft and found nothing in there as the ignition system has been changed. So after some research and talking tot he previous owner, I found out the ignition system on this bike is a newer stock Yamaha CDI ignition. As per the pics below you can see the ignition Unit and the single coil that ignites the two park plugs.
Now since we know what kind of ignition system I have does anyone have a diagram for this bike using a CDI ignition system or link to a harness etc..
Thanks for any and all your help.





 
Uh-oh. This bike's had some serious mods. Camshaft ends cut off, TCI ignition? Conventional answers no longer apply here. If it's had the later '80-up rotor/stator system installed, with the matching brush configuration, the '80-up charging system schematic could be used. But, that would need to be confirmed first, with good close-up pics of the stator housing and brush block.
 
I took the round covers off the cam shaft and found nothing in there as the ignition system has been changed. So after some research and talking tot he previous owner, I found out the ignition system on this bike is a newer stock Yamaha CDI ignition. As per the pics below you can see the ignition Unit and the single coil that ignites the two park plugs.
Now since we know what kind of ignition system I have does anyone have a diagram for this bike using a CDI ignition system or link to a harness etc..
Thanks for any and all your help.

Hi pkaczmar,
OK, the bike starts and runs?
With the '80 ignition it must have a battery.
Does the battery get charged or is it a dead loss system?
To charge it needs a regulator/rectifier.
To electric start it needs a minimum 14AH battery.
To work lights and signals you need a keyswitch and the stock handlebar switches.
I'd start with the post '79 wiring diagram in Clymers or the one you can find on this list to work out the wires you'll need.
How much of that do you have on the bike right now?
 
Alright 'TwoManyXS1Bs' took the covers off looked at the alternator and as per the pics, no brushes this seems to have been updated into a magnet system or something else.

'fredintoon' The bike did start when I bought it since then I can't get it to start seems the battery is dead and won't charge enough to turn it over, it was a 12V 5ah battery. The bike does not have regulator/rectifier. all the exists is the on/off switch, Ignition Unit and wires connecting it all, I assume that means a dead loss system. No light switches on the handle bars or key ignition. All the controls, brake switches, lights would need to be purchased, that's why I really meant 'starting from scratch'
Hope this narrows down my problems and setup.



 
Oh dear.
all you got is the rotor and the stator casing and all it's doing is using the little permanent magnet (use a thin feeler gauge to find it) in the rotor face (and that rotor face don't look quite like mine, could the trigger magnet be a DIY add-on?) and the Hall effect trigger (the oval plastic thing on the outside of the stator casing) to trigger the TCI box that fires the coil.
Which is fine and the right thing to do on a race bike but leaves you totally screwed for street use.
However, if the battery won't charge you can boost the ignition from a car battery to get the bike running.
 
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Well that's not the best news to hear. Does this mean no proper charging for the battery.
If this means Im screwed for street use where should I start? I'm assuming installing brushes and new alternator system?

And no the 71 never had an electric start. Its a kick.
 
Well that's not the best news to hear. Does this mean no proper charging for the battery.
If this means Im screwed for street use where should I start? I'm assuming installing brushes and new alternator system?

Hi pkaczmar,
Note that the '80 & newer alternator is a dual purpose device; the original electromagnetic rotor and it's surrounding stator coils have the TCI ignition's trigger magnet and Hall effect pickup unit piggybacked onto it.
What I see in your photos is (I think) an early rotor with a DIY trigger magnet buried in it and the empty shell of a late model Stator used to hold the Hall effect pickup in place.
All that's left on your bike is the ignition trigger, there ain't no charging system there no more.
You got options.
1) Go back to stock electrics.
2) Fit post '80 electrics less the e-start wiring.
3) Switch to a permanent magnet alternator and one of the aftermarket ignition systems.
I'd say go with #2) as being the easiest way to go but that's up to you. Troll this list's parts column for used stuff.
Lotsa XS650 builders swapping to PMA that could have stock parts to sell.
 
Hi pkaczmar,
as you are in Canada you'll be shopping at Mikes' Canadian outlet:-
http://www.xs650direct.com/products-29.html
But yeah, the PMA will work for power but you'll need to get a Pamco or Boyer-Bransden system for sparks and I think either of those will need some kinda pickup on the points system hardware that's been removed from your bike.
Or, MikesXS sells OEM replacements too.
#24-2656 & # 24-2652 will get you back to post '79 stock ignition and
will let you use the TCI and Hall effect pickup you already have.
But I get chided for giving opinions about stuff so you choose, eh?
Whatever you choose, get the rotor puller #35-0040 as well.
Claw pullers can work but can also wreck the rotor.
 
Fred's recommendation of option #2 may be your only choice. Since the camshaft ends seem to be cut off, you're stuck with a crank triggered ignition, which the PMA offerings don't provide...
 
Fred's recommendation of option #2 may be your only choice. Since the camshaft ends seem to be cut off, you're stuck with a crank triggered ignition, which the PMA offerings don't provide...

Hi 2Many,
#1) and #3) are also possible if the OP wants to tear down the engine top end and swap in a replacement camshaft along with it's mechanical advancer & points.
But yeah, #2) does seem to be the easiest way.
However, the project involves putting a race-stripped '71 XS650 back into road-going trim.
How much time effort & money is this going to take?
I see $400+ just in replacing the ignition and charging systems.
There's lights, wiring, fenders, seat and a paint job still to go.
Mind you, a restored back to original '71 will be a valuable machine once it's done.
 
Thank you for everyone's input, I think I'm almost there, wrapping my head around this.
So options 1 & 3 are definitely out of the question, im not ready for that.
So if I understand correctly best bet is to get the charging and ignition system to an 80's setup without the electric start this bypasses the use for points and uses the TCI box system which I already have.
Therefore I should be following the diagram below?
I have included part numbers from mikes xs just to make sure everything works with the other piece. Couple questions in there about the wiring harness (stock 80's or chopper?) Also about the pickup coil? And preferred battery 12v etc...
Hope you guys don't mind taking a look and letting me know where I am wrong.
Thanks so much again!
 
There is a little bit of wiggle room here. You'll need to keep your alternator housing, with that trigger unit and ignition box. You'll need to test that rotor, it looks cooked to me. If bad, you'll need the 80-up rotor with the trigger magnet. Since you suspect that your rotor may have been modified, you'll also need to confirm that your rotor's trigger magnet is positioned the same as a replacement rotor. Your rotor may already be an 80-up rotor.

Then you'll need a stator and mount screws.

Now, for the brush block, brushes, and their wiring. You could choose to go with either type of configuration. The 70-79 grounded brush system with matching regulator, or the 80-up powered brush system with matching grounding regulator. Can't intermix components here.

Rectifier: Doesn't matter, any of the 3-phase rectifiers will work. There is an economical 3-phase rectifier block on eBay.

Regulator/rectifier combo: Another alternative, use whichever type matches your brush block configuration. The included rectifier will work for either type.

Battery: Stock on these was a 5.5 amp-hour unit, you can do with smaller if need be. I'm using 4.5 amp-hour on mine.
 
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