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But who prays for Satan?
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Discussion Starter #1
Coil / Flywheel Setup
This is a super common issue, so here is a sticky, I'll try to add to it as I put more information together.
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The engine could not run without a spark, On the C1 / B1-rep (and most 2-stroke pocket bikes) the engine relies on the spark plug creating a spark at the right moment to ignite the gas mixture and power the piston back down to BDC (Bottom Dead Center).

The Coil and flywheel create and send this power to the spark plug at just the right time, we need lots of voltage because we need a spark that can bridge the gap it will run into when it goes through the spark plug.



The more voltage we can create and send to the spark plug the better we can ignite the gas mixture and by burning more fuel we make more power.

The gap between your coil and flywheel play a huge role in making this voltage.



In picture 1 we can see the Coil, on top, and the Flywheel on the bottom.

You should see that there are two holes where the mounting bolts go to hold the coil in place, the holes are tall enough to allow you to loosen the two mounting screws and move the coil up and down.

So, Start by removing the pull start / cover, now you should see something like in the pictures, loosen the two mounting bolts for the coil.



With the business card in place rotate the engine 360 degrees keeping the business card between the Coil and Flywheel, if you notice any “High Spots” on the Flywheel try to end the rotation with that high spot pushing the Coil as high as it will need to so it can rotate without touching the Coil.



Slightly tighten the two mounting bolts, you want to try to keep the coil from moving, but still need to remove the business card, so start to work the card out while tightening the mounting bolts more and more until both bolts are tight and the business card is all the way out.

Slowly rotate the engine at least 360 degrees (BY HAND!) making sure the Flywheel and Coil don’t touch.

Double check the two mounting bolts, and replace the Pull Start / Cover.

Pm nick for any questions / comments / additions! <---Thanks!
 

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Banned
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I my twisted crank engine it was hitting the bottom side of the flywheel, I set the gap at .060" at the magnets and it still hit on the bottom, the main bearings & pin bearing were shot.
 

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Hooligan
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8,578 Posts
Nice work on the sticky, Nick. I like the 3-D drawings showing exactly what should be happening. Maybe we should think about having you do this with more of the "how-to" threads.

Hey, maybe make a blue spark come out of the sprak plug boot! :D
 

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But who prays for Satan?
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Discussion Starter #4
My student version of the 3D software I use ran out, I will buy a full retail version this fall, $700 but we will be able to do some awesome stuff pretty soon, those are just pictures, soon will be full motion video as well!

PBP is on it's way back UP to the top!

Thanks for the kind words SpyGuy! :p
 

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Nick, Spyguy, EPR, Cam2 I just wanted to say thanks for all the info and hard work you all put into helping newbies like me. Thanks to you I have been able to correct some of my mistakes, and more importently avoid makeing them in the first place. Once again, Thank you for all the hard work.

Gar
 

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But who prays for Satan?
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6,571 Posts
Discussion Starter #6
You are WELCOME! When I got here in '05 I did not know anything about engines, 6 SHORT years later, I love all engines, gas, diesel, boat, motorcycle!

So, it is my duty to try and return the favor!

Thanks for taking the time to thank us. You Rock! :D:thumbsup:
 

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I started here in Aug of 2009, I had a diesel degree in college, owned and worked on everything from BMWs to Cadillacs, and 4 stroke Big Hondas and a Pro Stock Kawasaki 1015cc drag bike, and, I still needed lots of help, Nick help me get my first avatar photo and bike photos up.
I have learn So Much here about 2 cycle engines. The biggest one, Don't get in a big hurry, and put pistons in backwards and blow chains & the bearing covers of the clutch housing in to pieces when in turn it twisted my crank cause of the sudden stop, the two bolts were still attached, Made in USA, grade 8.8.
 

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Hooligan
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Gar, that's why we're all here, man .... helping our fellow riders get back up on two wheels. That's what it's all about on this forum.
 

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Awesome pics :cool:

Only things i think are worth mentioning as simple as it may seem is that due to the shape of the flywheel and space available the business card has to be cut into strips, i've been using two strips, one under each foot, which i hope is the correct way to do it!

Also as i might well be finding out on my own bike, business cards can differ in thickness which could create a problem, the magic number is .020" so is probably a good idea to measure the thickness of the card to be used first.
 

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Trained Chimp
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I always use the thick cards. The shiny ones with pretty pictures. Lol. The standard business cards are to thin. You need the good thick ones. 328 that is some good input. I have the same card I use. When one piece looks old and tattered. I just cut another strip.
Ps. Way to get sticky Nick. Nice thread. Great pics.
 

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I use to set mine at .010" but it can hit on the counter weight side. Like Cam2 said, .020" is good, so thats where I set mine now. After you set your coil, makes some complete turns off the engine to see if it rubs anywhere.
 
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