True Coil Tester

It's hard to confirm a coil is good unless you actually stress it. Even better would be if works after a thorough hosing down with water.

Works.

Sick!

Details and/or cost?

Nice item....your to smart for me.....

Stick your finger in there..... :woohoo: :woohoo:

There's not too much to add for details, other than:
The gap to jump should not exceed 1/2" for older coils and bikes.
Coils meant to run on higher compression motors 10:1 or greater, should be able to safely go about 3/4".

The coil being tested there is a 1977 KZ650 coil. I was putting it under more stress than it should have on it (it's a throw-away coil, but obviously still works pretty good, at least while dry).

The HEI module is the original 4-pin type. It should be on a heatsink plate, but the one I have there is probably overkill. It should only get slightly warm over 20 minutes or so.

Any standard motorcycle or scooter battery should provide more than enough power to run it for a long time.

The schematic is for a design requiring the coils are 2 ohm or higher resistance. A lower resistance coil should use a ballast resistor in series to make up the difference.

That particular unit is going to my buddy who does a lot of work on bikes.

Getting shocked is all part of the process on a project like that

That's pretty cool Lou.
Thanks for sharing.

JD

Just imagine, thread a piece of safety wire thru the seat cover on the drivers seat, stash your little box under the seat and wire it to ignition, set controls so it comes on with ignition.
Hide around corner and watch when owner gets in car and turns on ignition.

Run away, very rapidly!! :evil:


Got chased clear out the main gate at RAF Mildenhall by my very irate boss. The laughing gave me away, but it was so funny when his head hit the roof and he bit his cigar in two.

Still haven't figured out what I want to be when I grow up.



Gonna have to give this one some thought :evil:

:woohoo: :laugh:

bluej58 wrote: That's pretty cool Lou.
Thanks for sharing.

JD

x2

Awesome Lou.....

this is awesome, i need one of these.

Here's a video of two RD400 coils I tested for a friend. Whenever he tested for spark, he had it on both coils. But the bike would always sputter on one cylinder, then foul that plug.

It shows how a coil can seem to be ok at first, but can gradually go bad.



After closer inspection, we found the coil may have a possible leak at the wire attachment. We cleaned it up and replaced the wire. Hopefully it will work long enough to confirm the carbs are ok.

EDIT/update: After replacing the wire at the coil, it has been running great on both cyclinders.

I've been working on a new design for a tester since the HEI modules are now made differently. Also, this should prove to be cheaper since the driver costs about $5 instead of $20.

But while working on it, I realized I could make a controller to do this: