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[Adrian]

I bought one of those a while back for a project but changed my mind about fitting it in view of the poor output of the lighting coils. Interesting to find out that some LED bulbs CAN use AC - I do have a LED headlamp bulb that is supposed to be able to work with + **or** - earth, maybe that would work with regulated AC.



Don't know why Electrex World haven't offered something with a bit more clout in the lighting department for replacing Lucas alternators, when what they offer for Ducati singles seems a lot more powerful.



Ref switching the AC and DC lighting, why not just use a double pole switch, eg ebay item 142549497449?



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[Bullet Whisperer]

Hi Adrian, I have just fitted an Electrex crank ignition / generator to an Interceptor 750 and can confirm the output for lights is pretty feeble. Could it be that the Ducati singles probably spin a good bit faster than the R.E. singles and twins, that enables a greater output for them? Regards, Paul.

[Alan R]

Hi GUys------- An LED is a Diode that gives off light....but the important part of that description is the word DIODE----This is an electrical one-way valve if you like--- hence the tails are marked for +ve and -ve ......Now if you make a headlamp bulb that has 2 diodes of the same lighting value ( let's call it 1L for Lumens ) and connect them together in parallel such that the +ve of Diode "A" is connected to the -ve of Diode "B"..( and the reverse at the other ends )....and apply an A/C, 12v regulated current across those two connections then for half an a/c cycle Diode "A" will light and for the second half Diode "B" will light......The total light output being 2L .......( Incidentally if you connect this same bulb to a 12v DC system then only one diode will light up thus giving 1L output.).............The problem now is how to switch this bulb on and off at the same time as your rear lights using the usual 12v DC supply ??......Answer is}--- a Double Pole Single Throw ( DPST ) type..... ie}--one pair of poles for the A/C Headlamp circuit and one pair of poles for the 12v DC circuit, both being physically operated at the same time...At least that's how I understand it to be....

[Alan R]

Sorry---forgot to add}--- "As per E-Bay Item No. 142549497449" mentioned by Adrian

[Alan R]

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[stinkwheel]

Those switches are nice but I'm planning to use a neat looking LHS alloy switchgear off a Honda C90 for the lighting which has the off/side/main, dip and horn switch all on the same cluster along with a mirror boss and choke lever. The relay will do the same job as the DPDT switch and keeps the handlebar area less cluttered, it's just effectively moving the actual switch somewhere out of the way.

[Adrian]

Ref the Ducati singles kit, Paul, it is a completely different set-up, nothing to do with Ducatis revving faster! I quote from their web-site blurb:



"Complete replacement 120w generator system, including self generating digital CDI ignition with advance curve for single cylinder Ducati 250, 350, 450cc."



120W versus 50W, read it and weep!



Full details of Kit STK164 here.



http://www.electrexworld.co.uk/acatalog ... ml#SID=826



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[Adrian]

My apologies, the Lucas replacement kits are now rated at a whopping 65W!!!

[stinkwheel]

I'm assuming the problem with the power output of those is down to space constraints. With an external rotor, you by necessity have pretty small coils.



It did briefly occurr to me that you could potentialy fit a small car alternator on the end of the dizzy shaft and use a crank mounted, ignition only unit for the spark. But we're getting a bit silly there I feel.

[Adrian]

Well, the Japanese manage to get powerful enough alternators with external rotors, The Suzuki-style item which RE India copied for the Electra-X manages 100W, I think the EFI models manage a bit more with a few more coils on the stator (eighteen instead of twelve).



If you compare the Electrex World offerings for old British Bikes and the Indian pre-EFI/AVL Bullets with their Ducati stator kit, the 120W Ducati stator has twelve cores, NINE of which have lighting coils fitted, two are used for CDI charging and one is spare, while the 65W Lucas replacement offered for REs and BSAa etc, only has a four core stator with a only THREE lighting coils and one for CDI charging. Both stator kits have external rotors.



Meanwile, MIGHT it be possible to use an Alton AC generator (intended as a replacement for Lucas motorcycle dynamos) in the old contact breaker position? Never heard of anyone doing this, I have to admit.



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