Silent Hektic Ignition

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tricatcent
Cucciolo - the Lil Pup
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Silent Hektic Ignition

Post by tricatcent » Mon Aug 07, 2017 7:28 pm

I have a 75 900ss. It has a Silent Hektic Ignition. It has never worked properly. The previous owner had fitted this ignition and made a few wiring mistakes. Some of the wires were mixed up between the front and rear cylinder. It is easy to see how he made this mistake as the original instructions had a nice diagram, that was not labeled for which wires went to the front and rear cylinder. The previous owner had labeled the diagram himself but had labeled it wrong so everything was wrong after that.

With it hooked up wrong the advance didn't work correctly at all. I have had it hooked up right for a few years now but it still doesn't run right. I have experimented with different jets, checked for air leaks and now I am sure that the problem is with the ignition not the carburetor. The problem is that at very low engine speeds, idling and starting, any RPM below about 2000 RPM there is no spark on the rear cylinder. It is pretty hard to start. Above 2000 it runs great. It runs from 2000 to 7500 RPM really cleanly and is still pulling hard when I shift gears. The bike is very fast as it has high compression pistons and Imola cams.

What would cause this problem with the ignition? I am thinking of swapping the ignition pick ups and seeing if that transfers the problem to the front cylinder. That seems like the only cause that would not require a whole new ignition.

Nigel

Bern
Mach 3
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Joined: Thu Jun 10, 2010 6:29 am
Location: Toronto, On Canada

Re: Silent Hektic Ignition

Post by Bern » Tue Aug 08, 2017 2:18 am

They are inexpensive and work well and are pretty easy to set up..

https://store.bevelheaven.com/Electrica ... ort-GT-SS/

I added a ground wire from the battery that mounts at the clutch cable, it seemed to help generate a better spark when setting up my timing.

Bern
Mach 3
Posts: 98
Joined: Thu Jun 10, 2010 6:29 am
Location: Toronto, On Canada

Re: Silent Hektic Ignition

Post by Bern » Tue Aug 08, 2017 10:23 am

What trouble shooting have you done?

Since the front is working have you swapped the wire from the pickup to the rear coil to test if the coil, wire and plug are working when you manually turn the engine over with the plugs removed? I would rule this out before messing with the pickups.

Are the coils 3 ohm as opposed to 5 ohm? The 5 ohm coils work better at low RPMs as the 3 ohms will draw more current at low RPMs.

wdietz186
851
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Joined: Sun Sep 10, 2006 4:40 pm

Re: Silent Hektic Ignition

Post by wdietz186 » Tue Aug 08, 2017 6:14 pm

Being a squarecase the Dyna ignition Bern suggests won't fit your bike. You could try swapping the coils and see if the problem goes to the front cyl. I suspect [because it has bitten me before] that you might have too wide or too close clearance between the ign rotor and the pickup. The ignition is triggered by the collapse of the magnetic field as the rotor passes the magnet in the pickup. The gap between the pickup and rotor needs to be close to spec for the signal to be readable by the ign amplifier, too weak or too strong it will confuse things. It's worth a check if the coil swap doesn't do anything. Another thing to check is your battery voltage, too low [10.5v or so] will also confuse the ign box and the bike won't run.

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