Norton Commando 1969 timing issues

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yes I checked and set the valve clearance previously. I use a very thin guitar string to clean the carbs and followed bushman's site it's very good.
I haven't had time today to push start the bike but I will post the outcome it ASAP
thank you all
I have a 1970 Commando with the same problem. Boyer EI and a power box. Originally it was only firing on the left side, replaced everything coils plugs wires, reset timing nothing changed. Finally checked the Boyer box and found a small crack in it. So I upgraded to a newer version and away it went. It ran well for a few weeks then it started doing the same as yours. Kicks back
, pops, wont start, chugs a few times. So I'm at my wits end like you cuz I know it runs. I was advised to run 12v coils with the Boyer EI.
 

L.A.B.

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I was advised to run 12v coils with the Boyer EI.

o_O
That would be likey to make things worse (unless one or both 6V coils are faulty).

For Boyer electronic ignition the coils must be connected in series, the two 6V coils, therefore, share the voltage so each is working at around 6V.

Two 12V coils in series also get 6V each so won't give the same output as 6V coils.
 

maylar

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And 2 12 volt coils in parallel would be too much load on a Boyer. A dual-output 12 v coil is fine though.
 
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I ran a pair of Lucas 12V coils for years with a Boyer MkIII ignition. No problems starting or riding. I thought I read both 6V and 12V coils are supported in the Boyer documentation. Maybe I hallucinated it.

Now I use a dual 12V epoxy filled coil for space saving reasons only.
 

maylar

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Well, spark voltage and energy are directly related to coil current, so putting two 4 ohm 12 volt coils in series would be half the current and lots lower spark. Not that it wouldn't work, but certainly not ideal.
 

L.A.B.

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I ran a pair of Lucas 12V coils for years with a Boyer MkIII ignition. No problems starting or riding. I thought I read both 6V and 12V coils are supported in the Boyer documentation.

Two 12V coils can be used as Boyer states: "With this system two 12 volt coils can be used as long as they are in good order." but two 6V coils should perform better.

Pazon has more detailed information for their similar Sure-Fire ignition.
"Ignition Coils
When using the standard arrangement of two ignition coils (whether 12 Volt or 6 Volt), they must be connected in series, as shown in the wiring diagrams on page 7. Do not connect the coils in parallel. For low compression ratio engines (less than 9:1), two 12 volt coils connected in series can be used, but we strongly recommend running with two 6 volt coils connected in series or one 12 volt dual output coil with a primary resistance of 3 to 4.5 ohms."
 

DogT

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My Pazon Surefire works great in the original 70 6V coil setup. Although my coils are new, not original. They're not that expensive, good warranty and easy to setup. They also still need good battery voltage.
 
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Hi guys
Yes I set the valve clearance but at this point I can check it again.
So update I just came back from pushing the bike through a very steep hill
Previously put a tea spoon of fuel inside the barrels. Top of the hill ticked the carbs and second gear on the clutch. On my four attempts bike was going fast enough released the clutch and get a 3 three pops like almost starting the a bang and dies after even if I clutch again and open the throttle.
I push start bikes and cars before.
I have the compression tester bought already but please understand I am bundling up everything to order from the UK plus I am trying to figure out what other parts I might need. I will just order the new boyer EI and I will request my friend to send the stuff over in hopes of passing the customs without paying anything extra.
The carbs seem fine and I don't believe it's lack of gas. Usually pretty thorough but i can disassemble and recheck.
The coils are 6 volts and that's what they recommend for the MK4 when I spoke with Boyer support. I set aside the MK3 allready
I will try whatever you guys suggest besides selling the bike :eek:

Thank you all!
Also I am aware this thread is being very long also due to my inexperience. I hope that doesn't break any rules of the forum but if it does and you fell you need to shut me down I understand. We discussed many troubleshooting points on this post and I learned a lot. I am really grateful for all the help and suggestions and I can assure you I won't give up on the bike. I will recheck everything again while I wait for the parts!
 

DogT

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I still think it's the pilot port, or perhaps the Boyer. Are you sure you got the wire through the port. You can estimate the distance where the port is by the Bushman's article and measuring and the wire has to be long enough. And lots of times it's really hard to know you've even gotten the wire in that tiny hole.

If it's hard to push the kickstart over compression, I would think that would be plenty compression for starting.

I always found it better to roll start in 3rd gear. 2nd will often just skid, another sign of good compression.

Don't worry about the thread length. I think I hold the record. Or maybe Swooshdave.

It's just got to be some little stupid thing and it's hard to figure out sometimes if you haven't got a replacement part for everything it could be.
 
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The boyer is a new MK4 from the triumph t140. I put the Mk3 aside already!
I will check the carburetors and the valves again! just to be sure
 

RoadScholar

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I will check the carburetors and the valves again! just to be sure
Note the number of threads above the jam nut when you check/set the clearance. I'm thinking that, given the symptoms you described initially, that one or more of the valves may not be seating.

Best
 

concours

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Suck

Squeeze

Bang

Blow


Certainly, in nine pages of troubleshooting, a compression test was mentioned.
OP, was a compression test performed? Results?
 

cliffa

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The boyer is a new MK4 from the triumph t140. I put the Mk3 aside already!
I will check the carburetors and the valves again! just to be sure
Migsan, not sure if this was already suggested, but did you also swap out the stator plate? All Boyers have a common issue which is exasperated on the Commando. The wire strands break inside the insulation and cause a host of symptoms.

Cut the cable tie and move the wires, you may feel that they feel more flexible where the tie was, which would indicate they are broken.

Boyer_stator.jpg



There are many fixes for the issue, this was mine..



Have you also tried wiring from the battery direct to the ignition ( bypassing all the switches and connectors)?

Good luck. Together we'll get you going.

Cheers,

cliffa.
 
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Suck

Squeeze

Bang

Blow


Certainly, in nine pages of troubleshooting, a compression test was mentioned.
OP, was a compression test performed? Results?
I wasn't able to do it yet because the compression kit hasn't yet arrived but it's on the the list thanks!
 
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Migsan, not sure if this was already suggested, but did you also swap out the stator plate? All Boyers have a common issue which is exasperated on the Commando. The wire strands break inside the insulation and cause a host of symptoms.

Cut the cable tie and move the wires, you may feel that they feel more flexible where the tie was, which would indicate they are broken.

View attachment 78930


There are many fixes for the issue, this was mine..



Have you also tried wiring from the battery direct to the ignition ( bypassing all the switches and connectors)?

Good luck. Together we'll get you going.

Cheers,

cliffa.
Thanks for the help. I tried changing the stator plate already but I will check for the wires tomorrow to be safe. Today spoke with Boyer Bransden and they also suggested the following: "
The MK3 appears to have a reduced sensitivity to the signal.
If rubber mounted, check the earthing of the Norton's engine.
A bad earth can cause high voltage damage to the ignition unit, via the signal stator plate.
I will try and all of the suggested on the forum tomorrow
 

Saber

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I'm not a seasoned norton mechanic (yet) so i cant offer assistance. But I'm pulling for you and i am confident your persistence and willingness to follow guidance from this forum will get you going. And it will be good for all when that happens.
 
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o_O
That would be likey to make things worse (unless one or both 6V coils are faulty).

For Boyer electronic ignition the coils must be connected in series, the two 6V coils, therefore, share the voltage so each is working at around 6V.

Two 12V coils in series also get 6V each so won't give the same output as 6V coils.
I correct myself I just checked and they are 6volt coils
 
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