bsa lightning

[iansoady]

Very true. Gives me sleepless nights.....

[marty 31]

and I hope a happy ending is not to far away, its getting to be a embarrassment pulling up at the local sunday bikers meeting café standing talking for a hour, then kicking my little hart out, then a massive cheer when it rocks up, I will update, and thanks again

[R]

The moment its difficult to start, try putting a NEW set of plugs in it.
Perhaps not outside the cafe though....
And study if the plugs you take out are wet or dry.

[john.k]

Try turning off the fuel as soon as you stop the motor.......A hot flooded motor is near impossible to start,and that sounds like what is happening here.........As for the cheer,a friend of mine used to get a cheer when his bike started outside the pub,but the really big cheer was when it caught fire.

[TGR90B]

If the "magic box" is under the tank it might be getting hot when the bike is standing after a run. Just a thought.

[marty 31]

the problem persists, carbs needles lifted to weaken mix, resulted in running like a complete pig, so resorted in returning to makers settings starts and runs like a complete dream, but when heated up to normal running temp, just wont fire until a cardiac arrest is on the cards, then when it fires up it runs like a dream, the bike runs on electronic ignition and is timed bang on, so next try is going to be new 12 volt coils, does anybody agree and advise this? or am I just wasting just more hard earned money?

[L.A.B.]

the bike runs on electronic ignition and is timed bang on, so next try is going to be new 12 volt coils, does anybody agree and advise this?

As it has "electronic ignition" (which make/type?) then it's more likely to require two 6V coils (connected in series or one 12V dual coil) for best performance.

or am I just wasting just more hard earned money?

Possibly.

[marty 31]

the bike runs on electronic ignition and is timed bang on, so next try is going to be new 12 volt coils, does anybody agree and advise this?

As it has "electronic ignition" (which make/type?) then it's more likely to require two 6V coils (connected in series or one 12V dual coil) for best performance.

or am I just wasting just more hard earned money?

its boyer ignition with a duel small modern type coils which I assume is 12 volt as the rest of the bike, its a lot of years since I messed with brits but to me the spark always looked small, it also has a management box, that worries me because, how does one know if its working correctly? the engine is mechanically sound as its had a srm rebuild, so has to be either carbs or as I now suspect electrical 

Possibly.

[R]

how does one know if its working correctly

Engines are a number of 'systems', so each system has to be working - hopefully each at its best.
Spark plugs are a vital link in the chain - have you checked the plug gaps. ?

Reducing the plug gaps down is always a 1st step if you suspect that the spark is weak.
If this improves things, you know its (probably) in this area...

Determining the voltage of those coils might be useful to know too.

[L.A.B.]

its boyer ignition with a duel small modern type coils
 which I assume is 12 volt as the rest of the bike, its a lot of years since I messed with brits but to me the spark always looked small,

Which Boyer ignition?
The only Boyer ignition to use the miniature coils is the digital (blue box) Micro-Power ignition.

If it is the Micro Power then it would normally have one dual output 12V miniature coil.

 


Other Boyer systems such as Micro-MkIII, Micro MkIV, (both black box) and Micro Digital (red box) must use conventional coils, normally either two 6V coils connected in series or one conventional 12V dual output coil.

it also has a management box,

What make/type of "management box"? I assume you mean a regulator/rectifier?

[marty 31]

its boyer ignition with a duel small modern type coils
 which I assume is 12 volt as the rest of the bike, its a lot of years since I messed with brits but to me the spark always looked small,

Which Boyer ignition?
The only Boyer ignition to use the miniature coils is the digital (blue box) Micro-Power ignition.

If it is the Micro Power then it would normally have one dual output 12V miniature coil.

 


Other Boyer systems such as Micro-MkIII, Micro MkIV, (both black box) and Micro Digital (red box) must use conventional coils, normally either two 6V coils connected in series or one conventional 12V dual output coil.

it also has a management box,

What make/type of "management box"? I assume you mean a regulator/rectifier?

its blue box, the exact kit you have kindly shown, the exact same coils etc the modern type regulator/rectifier dosent seem to have a makers name on it, these modern add ons are all a good idea but bypass the makers manual, and the more ore less cheap process of elimination, thanx for the help so far, another thought is could the earth on the coils be maybe not good enough? as they are not earthed direct from the fixing because they had to be cable tied to the frame and couldn't be fixed to it,

[L.A.B.]

its blue box, the exact kit you have kindly shown, the exact same coils etc

You say "coils"? I assume you mean the single dual output coil as shown in the picture and not two separate single output coils?

If you do actually mean two separate single coils then how are they wired?

the modern type regulator/rectifier dosent seem to have a makers name on it, these modern add ons are all a good idea but bypass the makers manual,

Does charging system appear to be working normally? Have you checked the voltage (both battery and charging)?

another thought is could the earth on the coils be maybe not good enough? as they are not earthed direct from the fixing because they had to be cable tied to the frame and couldn't be fixed to it,

According to the Micro-Power instructions (below), only the (+) terminal (of the dual coil) has to be earthed (the coil body is plastic) and only if positive earth.

http://www.boyerbransden.com/pdf/KIT00281.pdf

[marty 31]

its blue box, the exact kit you have kindly shown, the exact same coils etc

You say "coils"? I assume you mean the single dual output coil as shown in the picture and not two separate single output coils?

If you do actually mean two separate single coils then how are they wired?

the modern type regulator/rectifier dosent seem to have a makers name on it, these modern add ons are all a good idea but bypass the makers manual,

Does charging system appear to be working normally? Have you checked the voltage (both battery and charging)?

another thought is could the earth on the coils be maybe not good enough? as they are not earthed direct from the fixing because they had to be cable tied to the frame and couldn't be fixed to it,

According to the Micro-Power instructions (below), only the (+) terminal (of the dual coil) has to be earthed (the coil body is plastic) and only if positive earth.

http://www.boyerbransden.com/pdf/KIT00281.pdf

yeah duel output exact one in the pic, and it has a new battery that charges fine, also its wired same as the makers diagram positive earth

[marty 31]

a update on my lightning problem, the coils were changed, the bike suddenly developed a sporadic misfire, fitting heat retarding spacers between the carbs and head resulted in the carbs being noticeably cooler, changing the coils back to the original, resulted in the bike now starting first or second kick, hot or cold, after changing the oil, replacing the gaskets between the sump plate and the casings and being mega careful, the bike is now 100% oil tight, running superb, starting and running correctly (hot and cold) a pleasure to ride, a success story, thank you to all involved in giving advice, all helping in the end result.

[iansoady]

Good news, thanks for coming back.