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Sorry, man. Got it as a link, but I couldn't get it to work as embedded.

Congrats on getting her running again!

Cheers,
-Kit
 

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Discussion Starter · #3 ·
nice one kit, ta!
im so pleased to have her running again, i can start getting all the other niggly little things sorted now!
 

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Discussion Starter · #5 ·
it was misfiring above 5k, and damned impossible to ride due to the misfire being intermittent, the power would "pulse in and out, well, thats not quite how i would describe it, more of a drop in power, then the coil would pick up again, and you would get a real unexpected surge.

but yeah, intermittent coil
 

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Discussion Starter · #7 ·
the coils are definately a weak point of these bikes.
and just to prove it, i went out on a nice ride to alton towers today (uk theme park for those that dont know.)
about 10 miles away, after aprox 100 miles with the brand new coil on, and one of the 2 remaining originals packs up.
i can tell you i was not impressed!
 

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Daytona,

Do you still have the old faulty coil?

If you do, could you measure the resistence on the primary coil (i.e. the resistence between the two flat-bladed electrical connectors) and also on the secondary (i.e. between any one of the flat-blade connectors and the HT connector).

I think I've maybe got a dodgey coil as well, and just wanted to compare with an identified faulty one.

The Haynes manual lists the specs for these coils as:

Primary 0. 63 Ohms
Secondary 10.5 KOhms

which given the +/- 10% tolerence means that this could range from:

Primary 0.693 to 0.567 Ohms
Secondary 9.45 to 11.55 KOhms

All of mine are 0.8 Ohms primary, and around 9.10 KOhms Secondary, so I don't know if they all are getting a bit of break-down due to age, wear & tear etc.

Cheers
Steve
 

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Discussion Starter · #9 ·
i can, and will later on when i find my multi meter, but to be honest, they dont just stop working, they become intermittent, so i think the readings would be about right even on a faulty one.
i will post back later, as to whether my assumption is correct or not
 

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What was the symtoms when your coil failed, currently I getting this:

Warmed the bike up, took a gentle ride (nothing above 4K) for about 8 miles, got onto the dual carriageway, wound the throttle open, sped up through the gears, next thing I know it's coughing and spluttering, then the power goes altogether (the rev counter falls to zero) and then suddenly it cuts back in again and I'm nearly thrown off the bike. It finally dies and I coast into a near lay-by.

Let the motor cool down for about 5 mins, start her up again and away. Surely one coil failure should'nt stop the whole motor? I can imagine it would run like a tractor, but this came to a grinding halt...

At one point in the bikes history, a Triumph alarm was fitted that's no longer in use, but still wired-up. I tried to remove it, but found that when I engaged gear with the side-stand up, it cut the motor out (maybe the wiring on the switch is reversed?); but the truth is I wondering if this crappy alarm is intermittently shutting the power off to the ignitor circuit (hence why the whole engine dies).

Any thoughts, enlightenment, I don't really want to buy three new coils if I can help it...

Cheers
 

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Steve, the entire motor cutting out sounds more like the pickup coil than one of the ignition coils. A failing ignition coil will make it run like... *ahem*, being the moderator, perhaps I should stick with your "like a tractor." :p

Having it run again after it cools down is consistent with pickup coil failure.

No guarantees it's not the alarm, but you are describing the classic symptoms of a dead pickup coil.

Cheers, HTH,
-Kit
 

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Discussion Starter · #12 ·
primary= 0 (start at something like 8 then rapidly drops down to 0)
secondary= 9.8

i think i just blew my theory right out of the water!

i must admit, your issue sounds more like a pickup coil issue to me.
when my coil failed, at certain revs it would drop down to 3 cylinders, then kick back in again (usually when i was negaciating a roundabout) giving me a sudden boost of power.

so, in conclusion, you may have an issue with both pickup coil, AND an ignition coil
 

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Cheers Guy's

Daytona, since your coil starts at 8 Ohms and then dwindles to 0, suggests to me that the coil windings are failing (i.e. completely shorting), which makes sense with your specific coil fault. Just as a yardstick, all of mine remain with a consistent resistence (i.e. the resistence albeit slightly out of tolerence with the spec remains the same). So I'm thinking that you probably 'did' have a confirmed faulty coil.

I'll follow the idea of an intermittent pick-up coil failure first and see if I can eliminate the fault down that route. First port of call will be to check all the connectors in the circuit and make sure they are clean & tight.

Kit, since the motors on these bikes seem to be built tanks, but their weakness appears to be the electrical gear, is it worth trying to get some form of sticky thread going that describes the top 5 electrical faults that owners of these 10 year+ bikes can expect to see and what the symptons could look like?

Just a thought, as I think Daytona is right in an earlier thread, it appears these bikes get to a certain age (or mileage) and then the electrics seem to start playing up (as if on queue...):)

more work...
 

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<...>
Kit, since the motors on these bikes seem to be built tanks, but their weakness appears to be the electrical gear, is it worth trying to get some form of sticky thread going that describes the top 5 electrical faults that owners of these 10 year+ bikes can expect to see and what the symptoms could look like?<...>
Yes, it is worth it. Alas, I just don't have the time to write it. Perhaps one of our more knowledgeable members with a clear, concise writing style could be persuaded? Else I may give it a go in a month or so...

Cheers,
-Kit
 
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