Where can I find a 1965 BSA Lightning wiring diagram? Bike was running great then just stopped - no spark. Has Boyer ignition. Tried new coils, Boyer module gets warm - not hot the Boyer seems to check out. Took off headlight lens and found some connecters not attached (but live with 12 volts) and none of the wiring colors match those in my manual. Last question - how to make the clutch "easier" to activate. My wrist gets awfully tired. Timmer
Easy part first, the clutch. Best option, buy & fit any one of the cast pressure plates with mushroom actuator. Then regardless of what pressure plate is fitted;- Adjust the pressure plate to get a square lift ( not as easy as it sounds ) When lift is square put the front wheel against some thing solid like a brick wall. Put the bike in 1st and back each nut off 1/6th of a turn at a time till the clutch just slips when you depress the kick start lever. Tighten each nut 1/2 turn Start the bike engage 4th gear and let out the clutch slowly. If the clutch slips then tighten each nut 1/6 turns and repeat till the engine loads and looks like stalling. Your clutch is now properly adjusted. Slack off the cable and using the center adjuster nut in the pressure plate adjust the clutch lever on the engine till it just makes a 90 deg angle with the cable at full clutch lift. Your pushrod is now properly adjusted. Now finally , ie the LAST THING you adjust is the cable, remove most of the slack so that the handle bar lever has 1/16" to 1/4". Go to a push bike shop and buy some gear change cable lubricant. Clean you old cable with kerro ( parafin to some ) , let it dry then apply the cable lube according to the instruction on the bottle. If the holes in either the lever pivot or the lever itself are any thing but 100% round then replace or repair them. Check that you have the correct shouldered bolt in the pivot ( some use a sleeve ) so that by tightening the bolt you do not pinch the lever onto the pivot.
Now for the sparks. 1) check the coils by connecting one side to the battery and making a flicking contact with the other battery terminal. If you get sparks then the coils are OK. 2) check ignition by reconnecting the - side of the coils ( one at a time ) . Turn on the ignition then make a flicking contact on the + side with the jumper from the battery. If they fire each time then ignition wiring is OK. 3) connect the Boyer directly to the battery and kick the engine. If you get a spark then the Boyer is OK and your ignition switch is suspect. 4) no spark above then measure the resistance of the trigger coils .
Bike Beesa Trevor
#411673 - 01/04/1212:20 pmRe: Wiring AND clutch on a 1965 BSA Lightning.
If it is a real live 65 with the type wiring and clutch, this answer will hopefully help. If it has been modified to some other type of clutch and wiring, just ignore the whole thing
1. Clutch - The 4 spring original clutch is a bit of a b@stard. Lots of things unique to the unit twin 4 speed, but other bits can be made to work. IME, I don't find a 4 spring anymore difficult to actuate than the 3 spring. If the clutch is pulling that hard, it is, IMO, broken.
If you have the correct clutch release mechanism, the engine should have a rear entry clutch cable. Not sure what bars you have, but cable routing is VERY important for easy clutch operation. IME, home market type bars give the best cable routing and clutch operation, high bars, not so much. The best cable routing is a gentle S bend from the clutch lever to the rear of the engine. The cable should only be lightly tied to the frame so it can move around during operation. Any tight bends or tight tie wraps will cause cable binding. The cable must also be well lubricated.
The clutch lever may have the wrong pivot length or mismatched lever.
If you have the original lever type release inside the engine, everything should move freely, there should be a ball bearing in the plunger that actuates the pushrod.
The cable to lever attachment at the engine is unigue If the adaptor between the cable and sleeve is missing, you are going to have issues with clutch release.
If you have the correct original pressure plate, the 4 spring cups are much shorter than the later 3 spring clutch. Use of later clutch springs will result in binding. Too tight of adjustment of the springs can cause the same problem. 4 spring cluches do slip if all stock and bit tired
Alloy pressure plates help a 4 spring clutch, but IME, they are a bit fiddly to make work with a unit twin 4 spring clutch. You need later cups from a 3 spring, 750 Triumph clutch springs (IMO), and an extra steel plate to use as a "stuffing" plate to keep the longer cups from bottoming out on the cush drive hub. You can also use later clutch packs, just be aware you may have to trim the tabs on the individual discs to get them to fit. The 4 spring also uses 1 less plate than the 3 spring.
2. If you have an original electrical system, it is "interesting" to say the least. The system used coil switching at the alternator to control output. If you simplify the system, you end up with spare wires that are hot in the headlight The ignition circuit had 2 potential hot leads. 1 was the normal white (if I remember correctly) that was the DC power during normal use. The ignition switch also had an "emergency" position that provided AC power in event of a dead battery (not unusual with the original system).
For that vintage, I have made my own wiring diagram to simplify the system to use a Podtronics charge control and the rest of the system much more like the later bikes. It also uses harness grounds for all components. Won't help you with your immediate problem, but if you want to rewire it, let me know and I will send you the schematic.
With all due respect to Trevor, I suspect a little clarification of his post might be helpful ...
However, one important thing that Trevor didn't mention is battery voltage and condition. We're talking about 12V e.i. but some - particularly B-B e.i. - can be sensitive even when the Volts are just above that but then drop below when a load's applied. Before fiddling with the e.i., you need to check with a meter that your bike's battery has well above 12V (ideally 13V+) and that it's capable of sustaining that with a load - a quick-'n'-dirty test with the headlamp has been posted on various Boards at various times, do a search, or have it properly load-tested by a battery shop or similar.
Originally Posted By: BSA_WM20
3) connect the boyer directly to the battery and kick the engine. If you get a spark then the Boyer is OK
Imho, this should be the first test. Trevor means the White wire from the e.i. 'box', that's currently connected to the rest of the bike's electrics, should be connected directly to battery -ve (assuming standard +ve earth/ground, ideally with a fuse in the connection). "If you get a spark then the Boyer is OK", so not a lot of point then fannying around checking the coils separately?
Only if the e.i. still doesn't work should you try the following:-
Originally Posted By: BSA_WM20
check the coils by connecting one side to the battery and making a flicking contact with the other battery terminal. If you get sparks then the coils are OK.
Firstly here, telling us which "Boyer ignition" your bike has would've been helpful. There are three different types (analogue (Micro)Mark 3 or 4 (black box), MicroDigital (red box) and MicroPower (blue box). This test applies to the first two only.
Assuming standard +ve earth/ground, one coil +ve terminal is connected already to battery +ve anyway? If whoever (you?) fitted the e.i. followed the Boyer-Bransden wiring diagram, the two coils should be wired 'in series' - i.e. one coil +ve connected to earth/ground, that coil -ve connected to the other coil +ve, only that second -ve connected by a Black wire to the B-B box.
Trevor's test is best conducted with that Black wire to the B-B box disconnected from the coil, a piece of spare wire long enough to reach battery -ve connected to that coil terminal and the other end used to make his "flicking contact" with the battery -ve terminal. Bear in mind that the coils will only charge when the wire end is in contact with battery -ve and the plugs should spark only when you remove the wire end from battery -ve.
Originally Posted By: BSA_WM20
check ignition by reconnecting the - side of the coils ( one at a time ) . Turn on the ignition then make a flicking contact on the + side with the jumper from the battery. If they fire each time then ignition wiring is OK.
This bit I don't understand so hopefully Trevor will clarify.
The previous test will have established whether both coils are working, so I don't see the point of connecting them "one at a time" to the "ignition?"; also, I don't see the point of "a flicking contact on the + side with the jumper from the battery"?
A. You haven't said whether the coils are 12V or 6V; if the latter, connecting 'em "one at a time" to 12V won't do 'em any favours.
B. There is an issue with trying to test continuity specifically with Boyer-Bransden (and Sparx copies of) analogue and digital e.i. - to prevent the e.i. overheating and/or flattening the battery, if the box doesn't detect 'engine movement' (via the trigger unit) within a very short period (ten seconds?), the box switches off, only switching back on when engine movement is detected. That's why, in the previous test, you supply the coils directly from the battery - trying to do it through the B-B box won't give you anything.
Originally Posted By: BSA_WM20
no spark above then measure the resistance of the trigger coils .
From this recent Triumph Board thread, if your B-B is an analogue (Micro)Mark3, the trigger coils' resistance should be around 130-140 Ohms, if Sparx copied that.
Thanks for all the tips. I will execute them this evening and get back to let you know the results. Just for clarification, it is the original harness, it base a MK III Boyer, I have a few other questions but not until I apply these suggestions.
My post is going to sound anti-climactic, but I got here late. Not to detract from anything that's been said about the clutch, but 90 percent of the time, if the clutch was ever ok and hasn't been messed with, the cause of a hard-to-pull clutch is a frayed, corroded, or inadequately lubricated cable. Before tearing into the clutch, remove, inspect, and either replace (if necessary) or lubricate the snot out of the cable. I've removed cables, and they felt "kind of okay", and then I oiled them, and wow, what a difference. My technique is to hang the cable from a stopper bottle full of oil until the oil runs out the other end. A crude stopper bottle can be fashioned by drilling a hole in the cap of an ordinary oil bottle, and wrapping some tape around the cable to make a seal in the hole. It will leak a little, but who cares? Just have a pan beneath. Also make sure the barrell end of the cable pivots freely in the handlebar lever (clean, grease).
OK so call me a dummy. I checked the engine number on my bike and it's a 1966, not a 1965. Having said that, I tested the coils as per your suggestions and very very weak apart and not every time. I checked both my 6 v coils and my 12 v coils. When I did get a noticeable spark (1 6v coil wired directly to the battery, I then wired up the Boyer and - no spark. I ordered a new Boyer and two new coils. Have a new battery so lets see how all that works. I considered getting a new harness but it worked well before so.......!!! Does anyone have a 1966 BSA 650 Lightning wiring diagram I can refer to? I think that would help along with the Boyer instructions that I already have...... Thanks (still haven't worked on the clutch issue - maybe tomorrow.....http://www.britbike.com/forums/images/icons/default/tongue.gif
OK. The latest: I replaced the Boyer Ignition and coils. Bike started easily, ran pretty good. Drove down to the gas station to get gas, the bike stopped, wouldn't start - no spark. Pushed it home, charged the NEW battery and it started no problem When the bike starts, the ammeter reads in the +, fluctuating quite erratically. Then it drops to the negative even thought the RPM stays the same. Looks loike the barrety is not charging however the positive indication on the ammeter seems to indicate that the alternator is working ok. I checked the diode with an ohm meter. current one way looks like this - 3 ohms from the first prong to ground. 6 ohms from the center to ground. 3 ohms from the third prong to ground. The zenner diode shows current only one way but I don't know how to check it. QUESTIONS: 1. What is a good way to check the out put of the alternator? 2. How do I check the zenner diode? 3. How can I check the current to the battery? This is a 12 volt,positive ground system. 1966 lightning I have a multimeter but don't want to arbitrarily stick it in line without good direction. One more question: I have 3 wires one side of the ammeter but all the diagrams I looked at have only 2. Finally, there are many unconnected wires in the headlight and I found a grn/brn "hot" wire with a quick disconnetor on it (male) and a grn/brn wire with a female quick disconnector on it. I joined these two - right or wrong??? This is a "stock" 1966 BSA twin with the only change being the Boyer ignition. it the above wiring digram ok to follow if I decide to re-wire the entire bike? Also where can I buy color coded wire? I live in Hawaii and don't have a clue. None of the auto parts stores carry the wire. Thanks.
Timmer, I think you may have overwhelmed readers with too many questions. Here's where I would start with the charging problem:
1. Start with a known good and fully charged battery. Check voltage across the battery with the engine off. Should be about 12.7 volts.
2. Start the engine, headlight off. Voltage across the battery should increase as you rev the engine, and should max out at around 14.2 volts.
If voltage reaches or exceeds 15 volts, you have either lost connection to the zener diode, or the zener diode is toast. I don't expect to see this though, since the symptom appears to be no charging, as opposed to over-charging.
If the voltage does not increase at all, or decreases, then the problem may be with the alternator or alternator leads, the rectifier, or a leaky zener diode. To eliminate the zener diode from the equation, simply disconnect it, and re-test.
I might point out here that often the problem is with the alternator leads. They run under the engine, and there are not-very-well-protected snap connectors right at the dirtiest and most vulnerable point. Check out these leads and snap connectors before going any further.
If you still haven't located the source of the problem, come back for an explanation of how to test the alternator directly.
Wiring questions: Find an accurate wiring diagram for your model year, either online, or obtain a service manual, Haynes, Clymer, or the factory service manual.
Wire in the correct colors can be obtained from British Wiring in Tuscola, Ill. They also have OE-type wire terminals and connectors if you choose to stay original, and complete wire harnesses as well.
QUESTIONS: 1. What is a good way to check the out put of the alternator? 2. How do I check the zenner diode? 3. How can I check the current to the battery?
I found a grn/brn "hot" wire with a quick disconnetor on it (male) and a grn/brn wire with a female quick disconnector on it. I joined these two - right or wrong???
This is a "stock" 1966 BSA twin with the only change being the boyer ignition. it the above wiring digram ok to follow if I decide to re-wire the entire bike?
The green/brown wires you connected would be either tail light or instrument wires.Do the tacho/speedo now light up,when they wouldn't before?
*If you connect the stator wires to a 60W headlight bulb and start the engine,you'll know if the alternator is working.The 60W bulb should light up well at less than 2000 rpm.Above 2000 rpm,you're likely to burn it out. *If that checks out OK,put the stator wires back on the rectifier.Disconnect the centre wire from the rectifier and join your 60W bulb between the centre terminal and ground.Start up again and the light should work about the same as before.It will be a little less,but you should still get 12V DC at the 60W bulb.
* It's not a good idea to run with the zener disconnected.You don't want 16V or 17V going to the Boyer.If the alternator works,the zener should limit battery voltage to about 15V maximum.If it won't reach 13.5V,replace the zener.If it goes too high,look for a bad connection/broken wire to the zener or replace the zener if wiring is OK.
*Your ammeter should tell the charge/discharge of the battery.The meter vibrates and the readings aren't always right.Voltage at the centre rectifier terminal should be about the same as battery voltage reading.
*The only thing that looks out of place on the wiring diagram above is the zener wire.It's normally connected on the other side of the ignition switch,so it's always directly connected to the ammeter and the rectifier output.The wiring diagram you want will be about the same as a '66 Triumph,both Lucas wiring.Google search "Classicbike.biz" and look in the Triumph repair manuals.
#415550 - 01/27/1212:06 amRe: Wiring AND clutch on a 1965 BSA Lightning.
[Re: Mark Z]
Joined: Jun 2006 Posts: 25Timmer
BritBike Forum member
OK. Tested out the charging system - appears to be OK. 13.2 volts across the battery when ignition is off. Start bike. Voltage goes to 14.9 - 15.1 at high revs. I cleaned the snap connectors from th alternator anyway. Still confused about why the bike stopped and wouldn't start when I tool it to the gas station. My next thing is to trace very wire and make sure the insulation integrity is good on all wires, Am going to replace electricians tape used on the harness (don't know why) with heat shrinking tubes. Ammeter still bounces bcd and forth like crazy. Original Lucas ammeter. Should I replace it? Thanks for all the help you guys. After tracking the motor number I guess I need to change my signature here. It is actually a 1966 lightning. Aloha