Magneto problem live!

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
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clive
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Magneto problem live!

Post by clive »

Waiting for AA outside Leominster to get taken back to campsite in Ludlow.
Symptoms. Bike rang perfectly starting and riding for 250 miles in last 2 days. Towards end of the ride today quick thrash of 1/4 mile to catch others and pulled up. Tickover ok went to pull away engine died. SR1 MAG No spark. Spare spark plug at campsite! Checked by taking plug cap off and no spark from cable end to head. Bent contact to ensure it is made with coil. Still no spark. Checked continuity by using cable instead of fuse and sounding horn.
When kicking over with cover off spark at points a couple of times but consistently no spark.
Any suggestions on what to check next?
clive
if it ain't broke don't fix
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dave16mct
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Re: Magneto problem live!

Post by dave16mct »

Have you got a spare condensor to try?
Dave.
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Rob Harknett
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Re: Magneto problem live!

Post by Rob Harknett »

Could be condenser, did you try undoing the pointed screw holding cable in the mag cover. Turn cable round and make new connection. ( not a common fault though ) Have you tried spark from lead, cap or connection duff ? points gap almost closed ? points wire earthing ?
SPRIDDLER
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Re: Magneto problem live!

Post by SPRIDDLER »

It sounds typical of a faulty condenser to me. I'm pretty sure you already know this Clive, but you can use virtually any vehicle condenser (from a motor factor/Halfords etc). It doesn't have to be a motorbike specific one. I've never had an SR1 mag but I believe the SR1 condenser is accessible and static (i.e. not buried in the rotating armature windings) so you can mount it outside the mag as long as its body/mounting bracket is earthed to the frame.

Have you tried for a spark now that the mag has cooled down?
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clive
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Re: Magneto problem live!

Post by clive »

Thanks for answers. Tried a new condenser from a Harley Davidson today. No success. Think it is the HT coil. Anyway back tomorrow via AA relay. At least we have a car here too and it is raining so there is some good news. I think i have a spare SR1 back in the garage. .
clive
if it ain't broke don't fix
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Pharisee
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Re: Magneto problem live!

Post by Pharisee »

That's bad luck. Anyone who rides these old machines regularly and over reasonably long distances ought to have some sort of recovery assistance in place. With the best will in the world, there are some things that can't be fixed at the roadside. I had an RAC membership for many years... They were good to start with, but the service deteriorated over the last few years to the point where, quite frankly, they were bl**dy useless. I just couldn't get past the "Please hold. Your call is important to us." message. When I changed my insurance to one of the classic bike insurers that advertise in the back of "Jampot", recovery was included. I've been quite lucky and only had to call for help once so far when the '71 Bonneville gearbox broke. The recovery truck was with me within an hour and took me all the way home. Excellent service. To be truthful, I've not heard much praise for the AA "Relay" system either, with stories of being left in motorway service areas for hours, waiting for the next leg of the journey. I hope you fare better.
John
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Mick D
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Re: Magneto problem live!

Post by Mick D »

Hi John

Did they really recover it on the side stand? :o

Regards Mick
Groily
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Re: Magneto problem live!

Post by Groily »

Very impressive the way they got those darn Trihard twins to run on an SR1 'n all!
SPRIDDLER
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Re: Magneto problem live!

Post by SPRIDDLER »

Groily wrote: Thu Aug 05, 2021 6:10 pm Very impressive the way they got those darn Trihard twins to run on an SR1 'n all!
In my opinion every type of ignition on a Harley is a wasted spark system.

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ajscomboman
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Re: Magneto problem live!

Post by ajscomboman »

I think the Chairman and President must have charmed lives, the thousands of miles we've travelled to IJR's and touch wood not required a recovery vehicle yet. We've come close with rear wheel speedo drive issues and dynamo bearings seize, 4 gallons of oil for 1200 miles etc (in one bike!). Always managed to make it back. That statement has probably scuppered our next escapade!! :rofl:
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