Cdi trigger position and running with no flywheel key??

T

ThePaetsguy

Member
How important is a flywheel key in a backyard 5hp engine?

It’s hard to explain but the flywheel magnets and pickup trigger can be put anywhere as long as I don’t use a flywheel key.. Can I run without one?? For ease of making a pickup trigger bracket can I just leave the key out and lock the flywheel down??

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Here's what I use:
Cast iron stock flywheel 65 foot pounds.
ARC billet aluminum with adjustable steel center 75 foot pounds.

With no key installed:
Make sure the tapers are the same (flywheel and crank.) Lap them well. Clean the lapping compound off, then set the ignition timing where you want it and torque the flywheel in place.


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🏁Thanks and God bless,
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Carlson Racing Engines
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You have this in the flathead section when one of your pictures (probably both) show a clone. You may be getting unintentional bad advice because of that. What engine are you putting this on and what flywheel are you using? Also curious what engine the ignition is off?
 
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Chipg56 said:
You have this in the flathead section when one of your pictures (probably both) show a clone. You may be getting unintentional bad advice because of that. What engine are you putting this on and what flywheel are you using? Also curious what engine the ignition is off?
Click to expand...
It’s going on 3-8hp briggs engines I have.

The pictures are from Danial Crenney who might still be selling this cdi system as a kit for ohv’s he builds..

The ignition is generic gy6

I GAVE UP making a coil bracket to put the trigger over the Briggs 5hp flywheel IN THE STOCK POSITION... The Briggs right coil mount post is in the way and making a bracket proved very tough.

Now that I know I can put the trigger and flywheel on without a key making the bracket will be easy.
 
Chipg56 said:
You have this in the flathead section when one of your pictures (probably both) show a clone. You may be getting unintentional bad advice because of that. What engine are you putting this on and what flywheel are you using? Also curious what engine the ignition is off?
Click to expand...
Good point for those reading along. I had seen the OP's previous post regarding using CDI on his flathead and assumed that's what we were still talking about. I think the photos he showed are simply of the cdi box and homemade brackets from the seller.

Sometimes we forget about others who might be reading along quietly on these forums. :)
Keeping everything in context is always a good idea.
 
Chipg56 said:
So is it a 8hp flathead (model 19) or an ohv intek (model 12 or 15)?
Click to expand...
I’m using OHV examples from Danial Creaney’s YouTube channel called

Cdi performance parts

He swaps these cdi’s onto predators/Honda’s and clone engines he has a lot of videos on his channel that helped me!

I’m just messing around with copying it on a briggs 3hp 5hp and 8hp engine for fun.
 
I paid $20 for this little 3hp and spent $35 in gas driving to pick it up.

I cleaned it up and made it look the best I could as seen in the second picture. Never put oil or gas in it I have never even heard it run... I think it’s more fun cleaning/painting them than it is actually using them...

I listed the little engine for $30 on marketplace all painted up nice ready for gas/oil and not one single person showed any interest at all.. It’s been shoved around the shed and scratched and I just never had a use for it..

Now it’s a test mule..
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ThePaetsguy said:
I paid $20 for this little 3hp and spent $35 in gas driving to pick it up.

I cleaned it up and made it look the best I could as seen in the second picture. Never put oil or gas in it I have never even heard it run... I think it’s more fun cleaning/painting them than it is actually using them...

I listed the little engine for $30 on marketplace all painted up nice ready for gas/oil and not one single person showed any interest at all.. It’s been shoved around the shed and scratched and I just never had a use for it..

Now it’s a test mule..
View attachment 32581View attachment 32582
Click to expand...
If you want to end up with a million dollars buying, fixing up, and reselling small engines it's real easy...
...just start with TWO million!!
Michael
 
I did end up taking a piece of steel and making a rudimentary ignition coil based off the stock Briggs coil.

ALOT of adjustment for timing on the slides on a 3hp.. I was also surprised to find the top of each slide is the exact bolt spacing for 5hp coil posts.

There is ZERO adjustability with the slides when bolted to a 5hp engine. The adjustment would be done with a flat blade on the CDI adjustment screw..
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Ok so back onto points it sounds like it could be rather simple? I might just r&d that myself or at least try to. If I can fire this off points with no AC or battery that’s a step in the direction I’m hoping to go.

Next two torque converters and 10t-60t gearing a wheelie bar with launch control through cdi spark cut. I read danial craneys posts he had a programmer for cdi’s just like mine but I’m having trouble finding info on that.

Tried to join his group to ask and blocked? I’ll figure it out myself if I can. I was thinking a resistor or led or some big load on the power wire to cause a power loss at low rpm’s with a button?

Then it’s loaded up and ready to launch when I let off the button? I honestly have a 3hp I couldn’t sell for $30 and a cdi system swapped onto it so cheap fun R&D in the front yard is no trouble. But a straight up solution to easy launch control written out would be best
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Ok so I have one kill switch already wired to the cdi I flip THAT switch and boom Briggs shuts off no spark.

NOW make a second kill switch that has a relay and just add it to the coil ground post.

Hitting the kill switch shuts the bike off and hitting the relay switch acts as a 2 step..
 
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What’s your clutch stall/engagement speed. Might be tricky to make launch control (using the term loosely here) to work with an automatic clutch?
 
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