Help. Can't get it running.

[Poopyboogin420]

pulled the magneto apart and cleaned it with some sandpaper today. there really isn't much to a magneto, so I don't see how it could go bad.

I cleaned the connections to the wires, and I cleaned the top of the plug.

Thats good...

I tried running alongside the bike (with the plug hanging from the coil wire and resting atop the motor) and when I dumped the clutch the motor spun over fine, but still no fire.

I closed the gap on the plug about halfway, and still nothing.

Did you use a gauge? should be .025-.030. I did mine at a few spots to find where the engine ran the best, I think .028 was where I ended up.

Where to now? I hate to simply start replacing parts on a brand new kit. I know they're not expensive...but I mean it's brand new, it should work.

I hope I've got everything hooked up right, it shouldn't be too complicated. I've got the black wire hooked to the black on the coil and the blue wire hooked to the blue on the magneto. That's it. It's an extremely simple system, I don't see where my wiring could be at fault.

You're on the right track, something is just not working, and I'm pretty sure its the ignition system. I'm starting to think it might be a bad CDI. Another member had the same problem as you(minus the rusty mag) and it turned out to be a bad CDI.

And that's it right? The magneto spins and the coil fires? right?

do you have to get going crazy fast before it works or something?

Shouldn't have go crazy fast, about 7 MPH or so... I hate to say it but I think you might need to replace the CDI, where did you get your kit? Whoever you bought it from might be able to replace it. Otherwise you should only be out $20, $25 or so. I know what you mean about buying new parts. Believe me. My motor just died on me after about 600 miles because there was metal shavings left over in the engine that ended up gouging my cylinder wall and causing me to lose compression. Even at that, I am still going to only shell out $50 to fix it, and this time I will flush the engine out before running it. They are cheap, and you have to expect some parts to be bad from the get go.

 

[Greg58]

If all is well with your ing. system it should fire while just rolling the bike along with the clutch out. I start mine by lifting the rear tire with the clutch out and spinning the tire by hand, it starts the first or second time. the coil has two wound circuits the one for the light (white wire) the blue is ing. the problem I have read is the wire is very small guage, so it can break under vibration. I had a problem with the first bike I built but had another kit to try parts from till I found the problem. If you e-mail BGF on the items below they will combine shipping.


http://cgi.ebay.com/80cc-Motorized-...Cycling_Parts_Accessories&hash=item2c587aa12c

http://cgi.ebay.com/bicycle-Motoriz...Cycling_Parts_Accessories&hash=item230b09f6d6

 

[rustycase]

Aw shucks!

Man! If you don't have spark, you got nothing!

Mags fail, but CDI's are generally the culprit.
and check you high tension lead, too... cut it off half an inch and re-insert it into position. Has the boot adapter been removed from the plug? Is that necessary???

Gosh I hate it when they won't start! :-(
rc

 

[maxsideburn]

Ok, cleaned the magneto and re-installed it, making sure there was a business card thick gap on each side.

I then tested the mag by hooking up to my multimeter and although I couldn't get any reading on it, it's definitely putting out some voltage. Even just barely pushing the bike you can see the needle jump up and down (just below 100 on the DC scale with the knob set to 10)

I removed the spark plug wire and re-inserted it onto the CDI....still no spark.

I am assuming the spark will be quite visible and audible like on a car. I certainly can't see or hear any spark whatsoever.

Is there any conclusive way to test a CDI?

 

[rustycase]

If you have installed a new plug, after what you have done, there is a probability the mag or the CDI are bad. Obtain them, and continue your tests, one at a time.

Sry, that's how it goes...
rc

...just make sure the wires to the CDI are correct! LoL
and NOT grounded

.

 

[ferball]

Late comer here, but did you change the plug wire yet? I had a no spark issue, it was a faulty plug wire.

 

[maxsideburn]

have not changed the plug wire, but I tested it for continuity and it seems fine.

what would I ask for at an auto store to get only one plug wire? they usually come in a set.


my CDI wires should be correct, blue to blue and black to black. I don't see how they'd be grounded...they're only connected to each other.

 

[DuctTapedGoat]

Black is ground, kill switch takes current from blues and puts it into blacks, grounding out the motor.

 

[ferball]

You can get a single wire from autozone if you if you ask for a distributor wire, it works fine as a plug wire just check the boot, some are straight instead of 90s. It is the wire that runs from the coil to a distributor. When my plug wire failed it was at the boot, I would get continuity, but when I inserted the plug it spread something out caused problems.

 

[rohmell]

Check to see if you have about 300-400 Ohms resistance between the blue wire and ground, and 2.0-3.0 Ohms of resistance between the white wire and ground.
If this is OK, then CDI is likely to be bad.

 

[Poopyboogin420]

Did ya get it fingered out? Let us know what you find...

 

[azguero]

hey i also have a similar problem but i took all my covers off everything is spinning except the magneto cant get it to start any ideas? also i will let u kno if it gets fixed maybe it will help u out as well

 

[Greg58]

If the magnet is not turning remove the right side cover, the one with five screws and check the clutch adjustment. or make sure the cable is not to tight.

 

[azguero]

i had all cover off the bike and tried pushing and got absolutely nothing from the magneto no turns at all but everything else was spinning fine,and my clutch cable is dosiconnected from the clutch arm for now as i do want constant spin to see whats up

 

[Greg58]

Is the small gear turning on the right side? if not remove the lock screw on the star adjuster and thghten the clutch . If the small gear is turning make sure the crankshaft key under it is not broken.

 

[azguero]

yep turning fine,whats that key look like?

 

[Greg58]

http://motorbicycling.com/f30/bicycle-engine-total-tear-down-391.html
Hope this helps.

 

[Bobby S]

Hello, I am having a similar problem. However before I try these solutions you have up here I would like to know if they fit my situation.

I just got my kit. I believe i installed it correctly. However my engine won't stay running. I can get it to start, but once it starts it runs for about 2 sec. and then slows down and shuts off.

I checked the spark plug and it has a spark, I don't exactly know how to test whether air is getting into the carb, but i know fuel is getting in the engine, and the carb. I tried to tighten the idle screw (because the engine came with it all the way out). Still I get the same result.

I tried to change the choke. When the engine is cold I turn the choke on. (the engine has only been warm once and that was after about 50 tries)

I don't know what to do?? do I need to buy a new spark plug just in case?? Do i need to get a new carb?? do i need to replace the CDI??

please help....

 

[Al.Fisherman]

Hello, I am having a similar problem. However before I try these solutions you have up here I would like to know if they fit my situation.

I just got my kit. I believe i installed it correctly. However my engine won't stay running. I can get it to start, but once it starts it runs for about 2 sec. and then slows down and shuts off.

I checked the spark plug and it has a spark, I don't exactly know how to test whether air is getting into the carb, but i know fuel is getting in the engine, and the carb. I tried to tighten the idle screw (because the engine came with it all the way out). Still I get the same result.

I tried to change the choke. When the engine is cold I turn the choke on. (the engine has only been warm once and that was after about 50 tries)

I don't know what to do?? do I need to buy a new spark plug just in case?? Do i need to get a new carb?? do i need to replace the CDI??

please help....

Definitely a new plug...a NGK will work great. Have you checked fuel flow to the carburetor? What is the compression. Just because you have spark, you need compression to ignite the fuel. Try a squirt or two of throttle body fluid, or starting fluid, into the carburetor. Since it will start I'm going to rule out electrical on the magneto and CDI for the time being.

So turns out the problem was a faulty CDI. Never would have guessed it because I was getting spark outside the motor. I guess it was just weak and possibly blowing out under compression.

Just wanted to share and thank everyone again for support!
L'eL

 

[Bobby S]

Definitely a new plug...a NGK will work great. Have you checked fuel flow to the carburetor? What is the compression. Just because you have spark, you need compression to ignite the fuel. Try a squirt or two of throttle body fluid, or starting fluid, into the carburetor. Since it will start I'm going to rule out electrical on the magneto and CDI for the time being.

I have never worked on an engine before so I am still learning. Does it matter which NGK spark plug i get?? How do you check the compression?? And what is throttle body fluid and how to you do that?? I am sorry for ignorance... And great that means less things to buy.