Magneto

73 views
Skip to first unread message

Mike Curtis

unread,
Apr 1, 2025, 8:55:03 PMApr 1
to guzzi-...@googlegroups.com
The adventures of Sparky. My Airone (54) started on the first kick in my driveway when it first came out of the box from Italy. It has continued to do so. I discovered that there was no spark when trying to start it recently. It was fine a few days earlier on start. I pulled the spark plug wire first. No continuity from plug cap through the mag bakelite fixture. Screwed the blakelite fixture off of the wire and found continuity from wire to plug cap. None through the bakelite mag cap. Spike in the cap appeared to be gone. Problem solved. Also checked and cleaned points at this time. New mag cap from Retro to Texas in 4 days. Screwed it on the wire and now have continuity end to end. Put it back in the mag with a grounded plug in the plug cap and…..no spark. Have no problem pulling the mag out but have no idea what I would then anyway. There must be more checks a prudent man would do before pulling the mag? Any prudent men out there? Actually imprudent suggestions would be welcome too. Thanks, Mike Curtis
Sent from my iPad

RICHARD YAMANE

unread,
Apr 1, 2025, 10:53:01 PMApr 1
to guzzi-...@googlegroups.com
Certainly clean/check the points and gap. I’ve had a few condensers go bad in the last few years. They have always been a start, die, start, die and start no more. Usually like a heat related issue. Condensers are usually pretty reliable but keep in mind, most of these magnetos probably still have original condensers in them. You probably would want to pull out the brush/plug wire holder too. Make sure the brush is still intact.

Rick Yamane
Importer of Vape/Powerdynamo ignition systems and Polisher of bikes at Motion Pro

> On 04/01/2025 5:54 PM PDT 'Mike Curtis' via Guzzi Singles <guzzi-...@googlegroups.com> wrote:
>
>
> The adventures of Sparky. My Airone (54) started on the first kick in my driveway when it first came out of the box from Italy. It has continued to do so. I discovered that there was no spark when trying to start it recently. It was fine a few days earlier on start. I pulled the spark plug wire first. No continuity from plug cap through the mag bakelite fixture. Screwed the blakelite fixture off of the wire and found continuity from wire to plug cap. None through the bakelite mag cap. Spike in the cap appeared to be gone. Problem solved. Also checked and cleaned points at this time. New mag cap from Retro to Texas in 4 days. Screwed it on the wire and now have continuity end to end. Put it back in the mag with a grounded plug in the plug cap and…..no spark. Have no problem pulling the mag out but have no idea what I would then anyway. There must be more checks a prudent man would do before pulling the mag? Any prudent men out there? Actually imprudent suggestions would be welcome too. Thanks, Mike Curtis
> Sent from my iPad
>
> --
> You received this message because you are subscribed to the Google Groups "Guzzi Singles" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-single...@googlegroups.com.
> To view this discussion visit https://groups.google.com/d/msgid/guzzi-singles/6F7CC02B-6EFB-4CF9-9F22-7A32FEFF1562%40aol.com.

RICHARD YAMANE

unread,
Apr 1, 2025, 10:54:44 PMApr 1
to guzzi-...@googlegroups.com
Oh, sorry, I was watching the Warrior game and skimmed past where you said you cleaned and checked the points.

Rick Yamane
Importer of Vape/Powerdynamo ignition systems and Polisher of bikes at Motion Pro

> On 04/01/2025 5:54 PM PDT 'Mike Curtis' via Guzzi Singles <guzzi-...@googlegroups.com> wrote:
>
>
> The adventures of Sparky. My Airone (54) started on the first kick in my driveway when it first came out of the box from Italy. It has continued to do so. I discovered that there was no spark when trying to start it recently. It was fine a few days earlier on start. I pulled the spark plug wire first. No continuity from plug cap through the mag bakelite fixture. Screwed the blakelite fixture off of the wire and found continuity from wire to plug cap. None through the bakelite mag cap. Spike in the cap appeared to be gone. Problem solved. Also checked and cleaned points at this time. New mag cap from Retro to Texas in 4 days. Screwed it on the wire and now have continuity end to end. Put it back in the mag with a grounded plug in the plug cap and…..no spark. Have no problem pulling the mag out but have no idea what I would then anyway. There must be more checks a prudent man would do before pulling the mag? Any prudent men out there? Actually imprudent suggestions would be welcome too. Thanks, Mike Curtis
> Sent from my iPad
>

RICHARD YAMANE

unread,
Apr 1, 2025, 10:59:45 PMApr 1
to guzzi-...@googlegroups.com
Another thought. Does your bike have a key?

Rick Yamane
Importer of Vape/Powerdynamo ignition systems and Polisher of bikes at Motion Pro

> On 04/01/2025 5:54 PM PDT 'Mike Curtis' via Guzzi Singles <guzzi-...@googlegroups.com> wrote:
>
>
> The adventures of Sparky. My Airone (54) started on the first kick in my driveway when it first came out of the box from Italy. It has continued to do so. I discovered that there was no spark when trying to start it recently. It was fine a few days earlier on start. I pulled the spark plug wire first. No continuity from plug cap through the mag bakelite fixture. Screwed the blakelite fixture off of the wire and found continuity from wire to plug cap. None through the bakelite mag cap. Spike in the cap appeared to be gone. Problem solved. Also checked and cleaned points at this time. New mag cap from Retro to Texas in 4 days. Screwed it on the wire and now have continuity end to end. Put it back in the mag with a grounded plug in the plug cap and…..no spark. Have no problem pulling the mag out but have no idea what I would then anyway. There must be more checks a prudent man would do before pulling the mag? Any prudent men out there? Actually imprudent suggestions would be welcome too. Thanks, Mike Curtis
> Sent from my iPad
>

RogerRowland

unread,
Apr 2, 2025, 4:51:02 AMApr 2
to guzzi-...@googlegroups.com
I know a bit about these happy to help, rebuilt mine as experts wanted a lot of cash to do so jamesro...@btinternet.com

Regards
Sent from my iPhone

> On 2 Apr 2025, at 01:55, 'Mike Curtis' via Guzzi Singles <guzzi-...@googlegroups.com> wrote:
>
> The adventures of Sparky. My Airone (54) started on the first kick in my driveway when it first came out of the box from Italy. It has continued to do so. I discovered that there was no spark when trying to start it recently. It was fine a few days earlier on start. I pulled the spark plug wire first. No continuity from plug cap through the mag bakelite fixture. Screwed the blakelite fixture off of the wire and found continuity from wire to plug cap. None through the bakelite mag cap. Spike in the cap appeared to be gone. Problem solved. Also checked and cleaned points at this time. New mag cap from Retro to Texas in 4 days. Screwed it on the wire and now have continuity end to end. Put it back in the mag with a grounded plug in the plug cap and…..no spark. Have no problem pulling the mag out but have no idea what I would then anyway. There must be more checks a prudent man would do before pulling the mag? Any prudent men out there? Actually imprudent suggestions would be welcome too. Thanks, Mike Curtis
> Sent from my iPad
>

Andrew Nahum

unread,
Apr 2, 2025, 6:09:49 AMApr 2
to 'RICHARD YAMANE' via Guzzi Singles
Agree Rick that the condenser is always a possible suspect - after continuity in HT lead - whether coil or magneto ignition. Some years ago my reliable Airone suddenly stopped starting! My excellent magneto guy found the fault and fitted this external Brit condenser as he didn’t have a Marelli one. Some people may consider it a historical crime but it is tidy and inconspicuous when fitted. Original is best but as I was on vacation and enjoying the bike I was delighted to get it off and back on bike in just two days, guided by excellent email instructions from Mike Peavey on preserving the timing and not ending up with mag drive gears on the floor!

image0.png
image1.png

Mike Curtis

unread,
Apr 2, 2025, 4:46:32 PMApr 2
to guzzi-...@googlegroups.com
Thanks men. All of your consideration is greatly appreciated. Lots of Moto Guzzi wizards in this group. Tip of the hat especially to Mike Peavey who often coaches me, sometimes twice a day, on the phone. The magneto spark emergency is terminated. The initial conclusion that the magneto cap was the culprit, was correct. Turns out it is very critical that it is installed in the magneto behind its little circle clip exactly squarely to make good contact. Starts on one kick again! Sparky, put your tools away.
Now, for the carburetor experts. All of my Falcone and Airone experience has caused me to think that these carbs were inappropriately maligned. Generally one kick to almost immediately an idle so slow you could almost count the revolutions. This Airone with the spark corrected, again starts with one kick but only runs on the throttle; will not idle and seems run out of fuel without significant throttle openings. Idle circuit? Clues on where to go? Thanks, Mike
Sent from my iPad

> On Apr 2, 2025, at 5:09 AM, Andrew Nahum <andrew...@gmail.com> wrote:
>
> Agree Rick that the condenser is always a possible suspect - after continuity in HT lead - whether coil or magneto ignition. Some years ago my reliable Airone suddenly stopped starting! My excellent magneto guy found the fault and fitted this external Brit condenser as he didn’t have a Marelli one. Some people may consider it a historical crime but it is tidy and inconspicuous when fitted. Original is best but as I was on vacation and enjoying the bike I was delighted to get it off and back on bike in just two days, guided by excellent email instructions from Mike Peavey on preserving the timing and not ending up with mag drive gears on the floor!
>
> --
> You received this message because you are subscribed to the Google Groups "Guzzi Singles" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-single...@googlegroups.com.
> To view this discussion visit https://groups.google.com/d/msgid/guzzi-singles/F06C1E27-CECD-44F9-9E0D-38105F38059F%40gmail.com.
image0.png
image1.png

Mike Curtis

unread,
Apr 2, 2025, 7:52:29 PMApr 2
to guzzi-...@googlegroups.com
Carb idle or low speed jet was almost or completely plugged with trash. Now back to 1 kick starting and idling. Thanks again.
Sent from my iPad

> On Apr 2, 2025, at 3:46 PM, Mike Curtis <lmci...@aol.com> wrote:
>
> Thanks men. All of your consideration is greatly appreciated. Lots of Moto Guzzi wizards in this group. Tip of the hat especially to Mike Peavey who often coaches me, sometimes twice a day, on the phone. The magneto spark emergency is terminated. The initial conclusion that the magneto cap was the culprit, was correct. Turns out it is very critical that it is installed in the magneto behind its little circle clip exactly squarely to make good contact. Starts on one kick again! Sparky, put your tools away.
image0.png
image1.png

Mac Dennis

unread,
May 10, 2025, 12:35:16 PMMay 10
to Guzzi Singles
These ignition systems want little to no resistance. Do you have a nonresident cap and plug?

Mac
> --
> You received this message because you are subscribed to the Google
> Groups "Guzzi Singles" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to guzzi-single...@googlegroups.com.
> To view this discussion visit
> https://groups.google.com/d/msgid/guzzi-singles/6F7CC02B-6EFB-4CF9-9F22-7A32FEFF1562%40aol.com.

--
Mac Dennis
capr...@fastmail.fm

John O Regan

unread,
May 10, 2025, 4:26:19 PMMay 10
to guzzi-...@googlegroups.com

Next step is to clean and check the points gap. Look for any loose or broken connections in and around the points area. If there is a cut out wire from the mag to a push button  try disconnecting it at the magneto.
You can also substitute the capacitor for a new one. Any automotive distributer capacitor will work fine. Blackened points suggest a faulty capacitor.
Resistance measurement from the HT lead to mag body should be in the region of 5K ohm.

John


Mike Curtis

unread,
May 11, 2025, 9:23:50 PMMay 11
to guzzi-...@googlegroups.com, guzzi-...@googlegroups.com
Thanks all.  Back to one kick hot or cold.  Some lessons:  the Bakelite cap in the mag needs sit squarely in it’s spot.  A new spark plug appears to the eye to make a hotter looking spark than the existing plug.  Mike

Sent from my iPad

On May 10, 2025, at 3:26 PM, John O Regan <chate...@gmail.com> wrote:



RICHARD YAMANE

unread,
May 12, 2025, 12:12:50 PMMay 12
to guzzi-...@googlegroups.com
While on the magneto subject, this is off Guzzi topic but.....
Does anyone have experience troubleshooting the BTH electronic ignition magneto? The is on my BSA RGS, I wanted to take it out yesterday for a quick oil warming ride but it wouldn't start.
I did move to the GTV and it fired right up so I rode that but upon return found the BSA had no spark. Just wondering if anything is a trouble spot on those. It's been flawless for about 20 years. I still need to pull the tank and check wiring so haven't really dug into it yet.
The GTV ran perfectly! Did a few laps around a long block. Building confidence in this bike. Getting used to the heel brake. Shifting is kind of graunchy but hopefully it is just break-in stiffness.

David Roper

unread,
May 12, 2025, 12:39:49 PMMay 12
to 'RICHARD YAMANE' via Guzzi Singles
I put a BTH electronic magneto on my Guzzi Falcone Spl. racer which worked great for a few races and then stopped working.  I sent it back to BTH in England and they said it sparked for them, but that they would replace all the internals anyway (which sort of sounded like a confession to me).  I put the rebuilt mag back on the bike and raced it at Barber with no problems. This year I race it at Roebling Road and it worked fine Sat.  Sun., I started it for the race and the motor died just as I was starting the warmup lap.  No spark.  When I got home, I took it off and spun it up with a drill and no spark with a new spark plug and trying different coils.  A friend of mine told me that he had a BTH electronic magneto and I should bring mine to his shop with my various coils and we would compare them.  Now my mag sparked on all of my and his coils.  I put it back on the motor and the bike started right up.  I have since raced it with no problems through the weekend, which makes me think it's an intermittent problem and that maybe it did spark for BTH when I initially sent it back to them.  I've talked to three other racers who say they've had a BTH fail on them and that BTH was always great about repairing them, but they don't trust it anymore.  When they work, they're great--easy starting; set it and forget it.  I'm going to continue to use mine, but if it fails again, that maybe the last time.  Before you send yours back to BTH, try it again and see if it sparks.

--
You received this message because you are subscribed to the Google Groups "Guzzi Singles" group.
To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-single...@googlegroups.com.
To view this discussion visit

David Roper

unread,
May 12, 2025, 12:43:43 PMMay 12
to 'RICHARD YAMANE' via Guzzi Singles

At. Barber 10/12/2024
On Monday, May 12, 2025 at 12:12:51 PM EDT, 'RICHARD YAMANE' via Guzzi Singles <guzzi-...@googlegroups.com> wrote:


--
You received this message because you are subscribed to the Google Groups "Guzzi Singles" group.
To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-single...@googlegroups.com.
To view this discussion visit
Falcone Spl. @ Barber 10:12:24.jpg

RICHARD YAMANE

unread,
May 12, 2025, 11:08:33 PMMay 12
to guzzi-...@googlegroups.com
Had some extra time this afternoon so I pulled the tank off. I found a wear spot on each coil and corresponding bare metal spots on the tank. No evidence of any arcing but as soon as I had the tank off I got spark back. Plan of attack is to modify the coil mounting bracket. I’ll put it in the mill and cut it down to lower the coils as much as possible. Add an insulating layer and probably add some cushion to the frame moving the tank up a couple mm.
It'll probably be a few days but I’ll drop an update for those interested.

Rick Yamane
Importer of Vape/Powerdynamo ignition systems and Polisher of bikes at Motion Pro

Reply all
Reply to author
Forward
0 new messages