HUGH'S PMA weak spark with SPARX CAPACITOR

ANLAF

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I have just fitted a Hugh's PMA and wired it (via the regulator/rectifier he supplies with it) to the battery - a fine, bright spark from both plugs when I turned the engine over with the kickstart (plugs out, and laid on the engine top to check the spark).

THEN

I disconnected the battery and wired the PMA (via Hugh's reg/rec) to the SPARX capacitor - very weak spark (can just make it out), and that only on every other kick of the kickstart.

It is a simple wiring set-up, and the PMA/battery combo tells me the PMA is doing its job, but what the heck - no start on PMA/SPARX combo.

HELP! have I missed something here.

Anlaf
 

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Well I would guess without the Sparx capacitor installed, all the voltage from the PMA is going through the ignition. With the Sparx capacitor, it's absorbing extra voltage like it is supposed to. Try starting the engine with the Sparx capacitor installed. My money says it will start just fine.
 
have you tried running the bike with the plugs in it?
The reason why I mention this is because.
The capacitor has to build up energy to store in its cell and when your looking at spark when your kicking it over it is not getting a full spark because there is not enough energy stored in it yet.
when you use the battery your getting a full blast because the energy is there and constant.
 
Just install the plugs in it and fire her up and youll be good
Once the engine is continuosly turning over the PMA will put enough energy in the capacitor and youll have nice spark
 
I am just fixing in my spare SPARX, but as I do I am right - red on the SPARX (two female terminals) I am working as positive, and the black (single female terminal). I say that because on the Lowbrow website next to the attached picture is their wiring diagram which, and I am no expert, I have difficulty in making head or tail of.

Second, Lowbrow sent me with these capacitors a piece of paper with the word "red positive earth as on most British motorcycle" - I am even more confused, I have an XS650 and I work on negative earth/ground.

Before I'm ready to kick this thing, have I got the wiring correct? Red postive, balck negative (ground)?

Anlaf
 
Here are the pics from Lowbrow

Anlaf
 

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Here is how it should be set up.

Black terminal goes straight to ground on the frame.

Red gets power from the rectifier on one of the red terminals and the other red terminal goes to your fuse block if your using one.
 
Ah ha! that's just a tad different from my set-up, so I will -re-route.

I appreciate the help fellers.

Anlaf
 

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I see in the pic of your diagram it shows you need to go to ground on the capacitor from the rectifier.... I wouldnt do that.. I would just do a ground from the capacitor to the frame and then on the rectifier go to ground as well you can use the same grounding screw...
 
The 20 main should go from the capacitor to your fuse box. And only one of them i saw two on there that is redundant. From the rectifier to the capacitor you shouldnt need any fuses so eliminate those. As for the ignition i have a pamco and i have 7.5 amp fuse for my ignition i do not know what boyer reccomends.
 
Thanks, thebalckassassin - I have another wiring update. My fuse from ignition to Boyer is a 10 amp in the fusebox.

Anlaf
 

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Looks good but Again remove the 20amp that goes from the rectifier to the capacitor And put it in between the capacitor and the fusebox or in your case ignition switch. Other than that all looks good
 
In case it isn't obvious, your headlight should be off and the brake light should not be on when you try to kickstart with a cap. They will steal valuable power that could be powering the ignition for starting.

The Sparx Capacitor was designed for Brit Bikes and is a copy of the ubiquitous Lucas Blue Capacitor. Brit bikes have the proper positive ground so those instructions are backward.

Tom
 
Thanks, Tomterrific - the switch for the lights is turned to off, but the wiring diagram shows the power through all four fuses, two to the lights, two to the ignition. Should there be a switch before the lights fuses?

And, thanks again - I got that re old Brit bikes.

Anlaf
 
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