Classic Triumph Bonneville

[JackyJoll]

If it’s hard to find 6 V stamped on the coils, a 6 V coil should show resistance across the LT terminals between 1.5 and 2 ohm. A 12 V coil should be 3 to 4 ohm.

These are approximate figures. They seem to be making coils with a lower current draw nowadays.

[David]

Fit a modern double ended coil.

[JackyJoll]

Fit a modern double ended coil.

Works for me.

[Le_Fromage_Grande]

Why would you have coils in series, that's just weird, surely if you've got two coils they trigger at different times?

[Taipan]

It's got the ones like this...



I did buy some of the kind which actually screw into the end of the cable, but they're too big to fit in the female side on the coil. The caps are new red NGK ones, they fit on the plugs without the little screw caps. Everything about the leads is brand new.



Having looked closer I can see the right HT lead is wobbly in teh coil. They just rely on being sorta wedged in there, they're not very secure. I like the idea of the silicone although I guess I could also try packing/wedging it with something. You can feel the left one 'connects' more solidly than the right when you push it in.

We used to shim 'em in with slithers of matchsticks. I'd use a bit of zip tie now. Still think it's yer float heights mind...

[David]

Why would you have coils in series, that's just weird, surely if you've got two coils they trigger at different times?

Idle spark, Dear......

[Le_Fromage_Grande]

Why would you have coils in series, that's just weird, surely if you've got two coils they trigger at different times?

Idle spark, Dear......

Then why have two coils sweetums?

[Mr. Dazzle]

You're not attempting to apply logic to old Brit bike design are you?

Edit: TBF though, if you look at the packaging it makes sense. One coil and one HT lead per cylinder, fairly easily located. Wasted spark every time, as your man says.

This bike is basically two singles flying in formation.

[Mr. Dazzle]

We used to shim 'em in with slithers of matchsticks. I'd use a bit of zip tie now. Still think it's yer float heights mind...

Yes I think so to.

I adjusted em cause they were miles off. Went for a ride and got surging and reluctance to rev, plus pretty clean spark plugs. So I made it richer (today) and went for a ride, it's a bit better but still not great.

Then I discovered the right plug is only half wired up.

So I will go back to my correct float carbs but UNDO today's richness adjustment, fix the plug and try again

[JackyJoll]

Why would you have coils in series, that's just weird, surely if you've got two coils they trigger at different times?

For electronic simplicity. The same black box can be used on four stroke single cylinder engines and 360 degree twins, by making the coil or coils spark every crankshaft revolution. That’s twice as many sparks as are needed, so it’s called wasted spark.

So far as my knowledge goes, wasted spark ignition first became widely used on Honda twins and Fours, triggered by points.

[Mr. Dazzle]

Wasted spark is/was the default on IL4s (I.e. middle two cylinders spark at the same time, as do the outer two) for many many years...its only really the introduction of coil on plug ignition that got rid of it. Talking both cars and bikes here.

[JackyJoll]

It wasn’t default on cars that had points in a distributor.

[Mr. Dazzle]

No

I was amazed that my Nissan micra had a mechanical dizzy. EFI and a distributor.

[David]

You're not attempting to apply logic to old Brit bike design are you?

Edit: TBF though, if you look at the packaging it makes sense. One coil and one HT lead per cylinder, fairly easily located. Wasted spark every time, as your man says.

This bike is basically two singles flying in formation.

A fairly loose formation.....

[David]

Why would you have coils in series, that's just weird, surely if you've got two coils they trigger at different times?

For electronic simplicity. The same black box can be used on four stroke single cylinder engines and 360 degree twins, by making the coil or coils spark every crankshaft revolution. That’s twice as many sparks as are needed, so it’s called wasted spark.

So far as my knowledge goes, wasted spark ignition first became widely used on Honda twins and Fours, triggered by points.

Fibber!


My LE has it.......

[JackyJoll]

Fibber!


My LE has it.......

So far as my knowledge goes

And the Velocette LE was hardly widely used.

[JackyJoll]

The Citroen 2CV did reach widespread use though.

[David]

Fibber!


My LE has it.......

So far as my knowledge goes

And the Velocette LE was hardly widely used.

Fibber again!

They were the mai stay of many local plod forces all round the country...my current one is ex I.O.W..

[Mr. Dazzle]

My other knackered old Triumph is ex-plod!

It's a 1965 "5TA"...which is not a 5TA at all. It's a 3TA with a 5TA engine, fitted by le filth before my FiL bought it off them in about 1970. He was shown as the first owner on that bike's V5, my wife is the second.

[JackyJoll]

Fibber!


My LE has it.......

So far as my knowledge goes

And the Velocette LE was hardly widely used.

Fibber again!

They were the mai stay of many local plod forces all round the country...my current one is ex I.O.W..

Tell me their production figures.