New CDI, bike won't spark (bike engine noob, need help!)

AntonioDAMAN · Nov 3, 2015

So, going from my previous thread I had created, I got a new CDI from Bikeberry for my 66cc engine (brand new, never turned over), but upon testing it all out, I'm STILL getting no spark. I've got the thing wired up like it's supposed to be, so it's really confusing me.

When I tested the magneto, I got a reading from it in the right area as per Bikeberry's specifications. However, I noticed when I pulled the magneto coil off the engine, that the magnet wasn't freely spinning - is it supposed to freely spin between the two ends of the magneto, where the coil screws into the engine? I'm just trying to learn and figure out what everything is supposed to be doing, so I can root out the issue and get this fixed.

Any help would be greatly appreciated!

KCvale · Nov 3, 2015

AntonioDAMAN said:
I'm STILL getting no spark. I've got the thing wired up like it's supposed to be, so it's really confusing me.

However, I noticed when I pulled the magneto coil off the engine, that the magnet wasn't freely spinning - is it supposed to freely spin between the two ends of the magneto, where the coil screws into the engine?

Any help would be greatly appreciated!

This will help.
http://kcsbikes.com/topic.asp?TOPIC_ID=623

I didn't cover magneto alignment to the magnet gap or the possibility of the magnet not being properly attached and messing up timing, it should help ya understand how it all works.

It's all easy with the good meter and understating of the easy system.

AntonioDAMAN · Nov 3, 2015

So, I'm already running into one issue with your guide - my CDI is different. You don't need to remove the nub on the end of the spark plug; in fact, my new replacement CDI came with a nub to put on the end of spark plugs if you don't have one.

Similarly, my magneto had no white wire, and the wires are soldered to the metal next to the coils, instead of the black wire being screwed onto one of the bars from the coil, like the one in the image you have. I'll take a picture of what I've got.

AntonioDAMAN · Nov 3, 2015

The magneto and how it sits in relation to the magnet. I noticed it's very hard, once I mounted the magneto, to turn the magnet, which I don't know if that's normal or not. There doesn't seem to be much clearance between the magnet and the arms of the magneto.

Similarly, the black wire being soldered onto the bottom arm seems iffy to me. Might see if I can't get a new loop, though this one tested fine.

crassius · Nov 3, 2015

don't forget to measure from blue wire to a ground on the head for mag reading in case there's a bad ground where it bolts on

with spark plug out, and clutch locked, magnet should turn fairly easily

2door · Nov 3, 2015

Slide a business card between both sides of the magnet and the coil before tightening the screws. That will provide you with good clearance. You just don't want them to touch.

Tom

AntonioDAMAN · Nov 3, 2015

2door said:
Slide a business card between both sides of the magnet and the coil before tightening the screws. That will provide you with good clearance. You just don't want them to touch.

Tom

Could that be why I'm not getting any spark from the spark plug/CDI/magneto?

thatsdax · Nov 3, 2015

There is no real way to check the black Box CDI. You can check the Magneto. Between the blue and black you should get 323 ohms + or - 5 percent. Since there is only the Magneto and CDI, if the Mag checks good, then the problem is CDI. 90 percent of the time it is Magneto. But I see a few, very few CDI's go bad. Rare.. But it happens. Make sure when you check for spark , do it in a shady spot so you can see the spark. These are not super hot sparkers. The 2 wire CDI is a hotter sparker and at my place of work, we are going to all 2 wire versions. White wire is useless. Also.. On your Frame adapter, use the Thick M6 nut or M6 Super nut instead of the Shallow M6 nuts you are using as they will not hold for long. Also.. one last note on Spark testing.. Do in the shade, and spin motor as fast as you can as it needs it to generate some voltage to trigger the Darlington Pair which excites the coil and generates the spark. Spin that sucker !!!

Enjoy the ride..

AntonioDAMAN · Nov 3, 2015

thatsdax said:
There is no real way to check the black Box CDI. You can check the Magneto. Between the blue and black you should get 323 ohms + or - 5 percent. Since there is only the Magneto and CDI, if the Mag checks good, then the problem is CDI. 90 percent of the time it is Magneto. But I see a few, very few CDI's go bad. Rare.. But it happens. Make sure when you check for spark , do it in a shady spot so you can see the spark. These are not super hot sparkers. The 2 wire CDI is a hotter sparker and at my place of work, we are going to all 2 wire versions. White wire is useless. Also.. On your Frame adapter, use the Thick M6 nut or M6 Super nut instead of the Shallow M6 nuts you are using as they will not hold for long. Also.. one last note on Spark testing.. Do in the shade, and spin motor as fast as you can as it needs it to generate some voltage to trigger the Darlington Pair which excites the coil and generates the spark. Spin that sucker !!!

Enjoy the ride..

When I tested the magneto, it gave me a good reading - I believe it was 327. Bikeberry believes it may be a "weak" spark, so something could be an issue with the magneto, which has me wondering if the magneto arms touching the magnet could be the issue, as it doesn't really freely spin; it's very snug. I'll try to reseat the magneto with the business cards like 2door said. Hopefully that'll work. I am going to test the CDI with Bikeberry's specs on their video and see what I get. It looks like it's in fantastic shape, so I'm really confused.

EDIT: Also, thanks for the heads up on the bolts. I do want to replace a lot of things, mounting wise. I don't think those bolts are going to hold either, lol. Then again, I'm not going to be riding it at WOT and over bumpy roads, since the bike doesn't have a suspension. If I could've fit the engine on the original bike I wanted to use (a 26" Schwinn mountain bike, hard tail), I'd be doing a bit more rough riding, but not with a cruiser.

crassius · Nov 3, 2015

lately some CDIs were giving weak spark - new CDI was the fix

AntonioDAMAN · Nov 3, 2015

crassius said:
lately some CDIs were giving weak spark - new CDI was the fix

Weird... this replacement CDI I got was brand new, looks to be in great condition. Good thing I'm going to have it tested tomorrow, once try resetting the magneto so it's not in contact/so snug to the magnet.

KCvale · Nov 4, 2015

AntonioDAMAN said:
So, I'm already running into one issue with your guide - my CDI is different.

Yep, magneto's changed in the course of that topic.
The useless white wire is gone and the winding wire got a bit thicker.

Yes the magnet is very close to the mag, I just use a scrap of paper to verify the 2 don't touch.

AntonioDAMAN · Nov 7, 2015

An update! I haven't had much time to myself this past week, so I just finally got to adjusting the magneto so it wasn't touching the magnet that it sits around. Tested for spark; still no spark. I'm wondering if the magneto is bad (or the wiring is, or something), since the CDI is brand new. Going to take the magneto and CDI to Autozone and have both pieces tested.

Really, really frustrating. I'm getting a very hard thought that this engine isn't going to be reliable for anything, even once I get it running, which is completely disconcerting.

2door · Nov 7, 2015

Autozone won't be able to check your parts unless they have the proper ohm readings to compare. They might be able to test for continuity but that's about all.

By any chance did you remove the magnet (rotor) from the engine for any reason? It will go on two ways. One way is right, engine will run, the other way is wrong, engine won't run.

Have you done the steps in the troubleshooting guide? Disconnected the kill switch from the circuit? Confirmed you have the wiring right? Black to black and blue to blue?

Are you using the kit supplied push-together connections for the wire? They aren't reliable. They can be installed wrong from the factory and not making an electrical connection. This is why we suggest soldering those connections or using a quality plug instead of the kit connectors. I've seen them crimped to the wire's insulation instead of the conductor. That won't work. Bad solder joints on the magneto frame can also cause you grief. Check those.

Tom

crassius · Nov 7, 2015

I've seen rotors come from factory installed backwards - there's a pic here somewhere showing how it should line up.

AntonioDAMAN · Nov 8, 2015

2door said:
Autozone won't be able to check your parts unless they have the proper ohm readings to compare. They might be able to test for continuity but that's about all.

I have the ohm's readings from Bikeberry to go off of, so there's no worry on that end. That's how I was able to have the CDI tested previously (and found it wasn't good; I was getting no reading from it).

2door said:
By any chance did you remove the magnet (rotor) from the engine for any reason? It will go on two ways. One way is right, engine will run, the other way is wrong, engine won't run.

I have not removed the magnet, no. I did notice there's no notch in the magnet like others I've seen online, so I may have to try that out; it may have been installed backwards, as crassius noted.

2door said:
Have you done the steps in the troubleshooting guide? Disconnected the kill switch from the circuit? Confirmed you have the wiring right? Black to black and blue to blue?

I have done that, yes, still no spark.

2door said:
Are you using the kit supplied push-together connections for the wire? They aren't reliable. They can be installed wrong from the factory and not making an electrical connection. This is why we suggest soldering those connections or using a quality plug instead of the kit connectors. I've seen them crimped to the wire's insulation instead of the conductor. That won't work. Bad solder joints on the magneto frame can also cause you grief. Check those.

That could be an issue (the connectors). Sadly, I don't have a soldering iron, so my next option, with that, is to splice the wires together and see if that works. As for the soldering joints on the magneto, they look okay, but I can't be completely sure. The magneto, when I had it and the original CDI tested a week or so ago, tested okay.

KCvale · Nov 8, 2015

AntonioDAMAN said:
I have the ohm's readings from Bikeberry to go off of, so there's no worry on that end.
That's how I was able to have the CDI tested previously (and found it wasn't good; I was getting no reading from it).

What do you mean by 'had it tested'?
You don't have a meter?

Do yourself a favor, get one when funds allow, you can get a digital multi-meter from Harbor Freight for ~$20.

The thing is, when looking for ohms it requires the meter be on the right range.
For example if you are on the 1K scale and you are trying to measure 2K it just shows 'open', mistaken for bad, Put it on the 10K scale and it reads fine.

Also, you can always test Ohms by touching the probes together, it should read 0.

AntonioDAMAN · Nov 9, 2015

KCvale said:
What do you mean by 'had it tested'?
You don't have a meter?

Do yourself a favor, get one when funds allow, you can get a digital multi-meter from Harbor Freight for ~$20.

The thing is, when looking for ohms it requires the meter be on the right range.
For example if you are on the 1K scale and you are trying to measure 2K it just shows 'open', mistaken for bad, Put it on the 10K scale and it reads fine.

Also, you can always test Ohms by touching the probes together, it should read 0.

I don't have a meter, no. That's why I took it to Autozone; they do electrical testing. All I had to do was tell them the parameters and what to test and they were able to test it for me. I'm a bit leery of buying from Harbor Freight, since I bought a chain breaker tool for this bike from them, and it got stuck on the chain that came with the kit, leaving me no choice but to buy another chain.

KCvale · Nov 11, 2015

AntonioDAMAN said:
I don't have a meter, no. That's why I took it to Autozone; they do electrical testing. All I had to do was tell them the parameters and what to test and they were able to test it for me.

Ya, Autozone is pretty good that way.
Ace hardware will sometimes do that as well.

I was weened on electronics, heck I had my own dual trace Oscilloscope when I was 24 and always have a couple good working meters.
In world of electricity everywhere they get a lot of use.

I'm a bit leery of buying from Harbor Freight, since I bought a chain breaker tool for this bike from them, and it got stuck on the chain that came with the kit, leaving me no choice but to buy another chain.

I have that same breaker. There are different size tips for pin size but I just ground mine down.

HF is definitely known for sub par products, kind of like gasbike, but even the junk can work for awhile and that may be all you need, and sometimes you do get lucky with something that lasts.

Anyway, just a tool tip and I hope you find your problem.

AntonioDAMAN · Dec 9, 2015

I have an update for everyone! I got a new magneto, as the other one I had, that came with the engine, was bunk. I have spark now, but a different issue has arisen: when I let out the clutch to get the bike to turn over, I get a very awkward squeaking noise, matching the piston moving up and down in the cylinder. Also, the rear tire is grabbing really hard and not wanting to turn.

Any help here? Really frustrated with this whole build; it's been nothing but issues. Really probably shouldn't have gotten the kit. :|

New CDI, bike won't spark (bike engine noob, need help!)

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