Trying to revive a 1973 Roadster

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GUTS said:
A continuity test on the black/white wire and the black/yellow wire shows good from the coil connection to the points.

After all this I do have lights and brake lights with the key in the proper position but still no spark at the points. Which coils do you guys recommend cause it seems I need to buy a couple.
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Given what we know, I would not-as yet rule out the possibility that something may isn't as it should be, having two failed coils at once does seem unlikely although not entirely impossible.
Could you clarify what you meant by: "no spark at the points" presumably you meant no spark at the spark plugs?

So, can we take it that you checked the points gaps and removed both spark plugs, fitted the plugs to the plug caps, and with the plug bodies resting against the cylinder head, with a wire from battery negative connected directly to each coil negative, neither plug produced a spark when the crank was turned?

As it was a photo that eventually led to the previous problem finally being identified, then perhaps a few photos of the coils and points assemblies might perhaps show something that is amiss, but could we be lucky twice?

Previously, you said one points wire was bad, now apparently both are good, so, what happened to alter this?

Did you remove either of the points wires from the points terminal posts at any stage during the checking process? As it's relatively easy to get the assembly sequence wrong when refitting the ring terminal which results in the points wire being 'grounded'.

Do you have volts at the white/yellow ignition wire [WY] going into the rubber block connector?
Note that the white/yellow connects to white/blue [WU] at the rubber block.
 
I thought I would eliminate the chance of a bad HT lead or a bad spark plug cap so I removed the HT leads and hooked the negative side of the coil to the negative side of the battery and the positive side of the coil to the positive on the battery to see if I at least had power at the points(I thought I should be able to see a spark when you roll the engine around). The points wire that was faulty had a bad connection that I cleaned and tightened up.
 
You won't get a spark by connecting both coil terminals directly to + and - battery. The spark is produced when the low voltage field collapses. This means you need to keep the points/condensers in the system. Hooking your 6 volt coil directly to a 12 v battery for an extended time is not doing it a favor.
Do as LAB suggests. put everything back together and test for spark with plugs resting on engine. First priority make sure your ballast resistor is good. Check for voltage before and after ballast and at each - coil connection. Your close to solving this
 
GUTS said:
I thought I would eliminate the chance of a bad HT lead or a bad spark plug cap so I removed the HT leads and hooked the negative side of the coil to the negative side of the battery and the positive side of the coil to the positive on the battery to see if I at least had power at the points
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Connecting the positive side of the coil to battery positive effectively bypasses the points.

The points are there to "make" and "break" the coil connection to ground, and it is this which produces the HT spark from the coil.
If you removed the HT leads, plugs and caps then you won't be getting any sparks. What you need to be doing is checking for sparks at the plugs when they are connected to the coil HT and 'grounded' against the cylinder head.
 
Just came back in from the big test, nothing, 0 spark. I went over the harness again and what do you know, the white/yellow stripe wire had become disconnected from the white/blue stripe wire from my hamfisted harness wrestling. I hooked it up and now I have SPARK! I name this bike Lazarus. I am going to tidy things up, check the points gap, put the tank back on and see if she will run. Thanks again guys! :D
 
GUTS said:
Just came back in from the big test, nothing, 0 spark. I went over the harness again and what do you know, the white/yellow stripe wire had become disconnected from the white/blue stripe wire from my hamfisted harness wrestling. I hooked it up and now I have SPARK! I name this bike Lazarus. I am going to tidy things up, check the points gap, put the tank back on and see if she will run. Thanks again guys! :D
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:mrgreen:

First, the bike tears you down... only to build you back up later :p Check for oil return as soon as you start....
 
Now I told you they were perfectly simple . :)

Bbb ballast resistors only needed with 6 volt coils , which are the last thing you need .

2MC is to get ' batteryless ' starting . Its a thing where you swing the injun over twice , to charge the @MC - Then turn ON Ign. and fire off first swing . Or do it all again . Not needed unless you need it .

You can see the virtues of throwing in 1/2 a dozen wires , and throwing out EVERYTHING that is NOT needed . If its Not There , it cant go wrong . It also doesn't weigh anything .
Which is why some people throw out the BATTERY , and use the 2MC . Severe cold weather could be a pain , start up , batteryless .

One of those little ' multi meters ' should test the coil capacitors ?? .

TECNICALLY , capacitors & coil - if matched - will minimalise points erosion . If its all one side somethings out , if its the other side - its out the other way . If its Just Right - there'll be minimal points pitting / wear .

Importance of MATCHED ' fire point ' on both cylinders cant be overemphesised , as if there were three cylinders , youd have THREE different ' impulses ' , with two big ones its even more dramatic - though the iso's
isolate the roughness - so you cant pick even 10 degrees disparity . If she's running like a Bought One - keep a eye on the Tacho till your familiar with the ' Vibes ' / Sound . Some 18 yr old turkeys reved Combats to 8000
cause theyed do it . Max. CONTINUOUS rpms are 5900 ( autobahn etc ) keep under 6000 in first & 6500 in 2nd , due to accelerometry & tach lag , if your hoseing Kwackersikis . :D :wink: . :?
 
I got home a little while ago and turned on the gas, turned on the choke, hit the ticklers and it fired up on the third kick. It seems to run really good. I haven't went for a ride(have to wait till this afternoon)but I think it will be fun. Thanks again for the great help you guys! :D
 
GUTS said:
I got home a little while ago and turned on the gas, turned on the choke, hit the ticklers and it fired up on the third kick.D
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Yee-haw! So, ultimately, what was the root cause of the no sparky? Was it the decomposing gang connector?
 
I would say that was most of it, like Guido said in the first couple of replies those connectors are very shoddy. I had also burned out the 2MC early on and was doing my coil tests like a moron and had stuff hooked up backwards part of the time. :oops: I have to tighten down the gas tank, install the front brake hose and bleed the brakes, tie the battery down and put the ignition switch back in, then it's time for a ride(it's licensed and insured). :D
 
I just got back from the first ride, it went pretty good. This bike handles nice but I need to some carb setting and adjusting. It starts first kick and runs good up to about half throttle and then it loads up, stumbles, and blows black smoke. This is going to be a fun motorcycle. :D
 
GUTS said:
It starts first kick and runs good up to about half throttle and then it loads up, stumbles, and blows black smoke.
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Are you operating the choke lever correctly?
For Amal Mk1 carbs, when the choke wire is TIGHT, the choke is OFF, and slack, it is ON. This is opposite to how many choke levers operate.
 
So true with the choke lever. Get off the choke A.S.A.P. too as a super-rich mixture washes oils off of cylinder walls when you need oil to be there the most. :|
 
I love you guys. :wink: The backwards English choke(no offense)was on. I just took another test ride and after backfiring a touch and blowing a flame out the exhaust it runs great! I am going to change the oil and go riding!
 
You have reached a new level in The Force. Yoda would have you treat all troubles just as you have the no-spark.

Trying to revive a 1973 Roadster


Nathan
 
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