I found the problem!

E

Eric2.0

New Member
I got a new Multimeter and followed the instruction on this site. The CDI box is dead.

See this then read on...thank you.

96500873.mp4 video by Dirtcar28 - Photobucket

1) Check Ohms between BLACK wire and WHITE wire. Reading should be around 2 Ohms
Click to expand...

*2.4 OHMS

2) Check ohms between BLUE wire and WHITE wire. Should be around 300-400 ohms.
Click to expand...

*333 ohms on the 2k range...0 on the 200 range.*

CDI


1) Positive lead on BLUE wire and Negative lead on BLACK wire should read infinite (no activity)
Click to expand...

*NO ACTIVITY*

2) Positive lead on BLACK wire and Negative lead on BLUE wire. Should be about 130-150 K-ohms
Click to expand...

*NOTHING*

3) Positive lead on Spark Plug wire and negative lead on BLUE wire. Should read between 135-155 K-ohms
Click to expand...

*NOTHING*

Switch to Low Scale 20K
4) Measure between Spark Plug wire and Black lead. Should be about 2.5 - 2.7 K- ohms
Click to expand...

*PULLED 2.4 OHMS.*


I did the testing exactly as showed in 2Doors post with the meter ranges suggested. I believe the CDI is junk and want to upgrade... Who has a better quality CDI or could I use one off a car or lawn mower? I'm not geting another stock one..they are JUNK....Just the way the plug wire goes in proves how junky they are.
 
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Eric2.0 said:
I did the testing exactly as showed in 2Doors post with the meter ranges suggested. I believe the CDI is junk and want to upgrade... Who has a better quality CDI or could I use one off a car or lawn mower? I'm not geting another stock one..they are JUNK....Just the way the plug wire goes in proves how junky they are.
Click to expand...
Did you get a "good" CDI and get your bike started?

I always found it kind of tricky to test CDI's so would test a
maybe bad CDI against a known good CDI.

I just swap them out as it's much faster and easier as I have lots
of parts including CDI's

Yeah, they are junk....lol another noob "expert"
Out of over 500 kits maybe one went bad and that
was a maybe.

Bad magnetos were much more common but still pretty
rare and they are easy to test.

If you got a bad CDI just buy another one, there is no
need to reinvent anything.
Someone has to get a bad CDI and maybe it was you?
Upgrade the plug wire, it is easy and looks better. lol

Let us know when you get it running. It will be a happy day.
Good luck.
 
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I'm going to put the one off my old snow-blower on there "just to see" If it runs I may just keep it there. I remember an old Yamaha dirt bike I had with a 125 on it and we put an old fashioned car coil on it....worked great for years.

The stock CDI for these things is 29 bucks.....I'm not taking another chance at a dead CDI at that price. Has to be other options.
 
This.... Wolf Pack Racing CDI Kit

Also I found this as a quote..

"Is there any possibility of danger to my engine by using this CDI? None at all. This is what the cheapskate Chinese should of put on it to begin with. Instead they included a CDI/coil combo that only advances (4 stroke style) and puts out the weakest of spark. Maybe they did this on purpose to keep the engine underpowered so it would pass legal requirements in most all countries."

AND THIS..

"Why is yours more expensive than some other CDI's? Because mine isn't made cheaply by slave labor in China. I value my employees and pay them well. Also my CDI, unlike all others, is especially designed for the Grubee engine. All others are either made for 4 strokes (that don't retard the timing at high rpm's) or they retard the timing over 7000 rpm (for heavily modified engines that rev up to at least 9000 rpm)."

I'm sorry, but those stock CDI are junk and I'm willing to shell out extra money for the American made CDI I linked too, because to make this bike more reliable for my dad(who is 67) is worth it to me.

Even has an MSD ignition wire... I'm so ordering this today.
 
Oh most likely it didn't trip the stupid whatever in the CDI box. I give up. Wait a week only to have the same deal with the new CDI.
I even got an extra Magneto just in case.

I don't get it. If it isn't the CDI box then I have no clue at all what is going on. I get **** loads of gas dripping out the pipe and a "sort of run" condition where I pedal for 100 feet, stop and the engine just goes.. Brrrrrmmm brmmmmm put put duh...dead. It's a very week sounding run, but it does try to run, sort of muffled like half the gas is igniting.

I don't know man....this is frustrating beyond belief with people looking at me like "is it running yet?" Pisses me off
 
To add insult to injury, My Neighbor asked me if I wanted a Huffy Big Daddy he got from the air base(Soldiers leave things behind)

Nice bike, but I told him I have my hands full with my current. I'd rather let a kid have the Huffy.
 
rohmell said:
Tomorrow I am gonna take the measurements off of my magneto and CDI using various different types of analog and digital meters and post a chart.

Electronic devices can sometimes be tricky to teat and diagnose out of circuit, so don't be upset about your test results.

This problem WILL be solved, and you WILL be riding very soon.
Click to expand...

That would be very appreciated and great. Not only for me, but for others wanting to test these right. I assumed red positive black negative always....go figure...I just don't get why they would switch it.
Also my meter is new from Harbor Frieght(the best one they had) and it has vF-and all that stuff. Also a temperature meter and audible continuity test.
Again, thanks for taking measurements....I need to compare to something and know how to do it better.

At least the CDI is cheap $$ and I'll throw it on to see if it works...I just need to remember to not kick something if it doesn't work.:-||
 
Ok I'm using a Cen-Tech P37772 digital Multimeter. I turned the knob to the Diode symbol as that is all I saw having to do with diode testing. It was in the area of the ohm ranges.

This is what I got from following your guide to the tee.

1. Nothing, it just said 1
2. .592
3. 1.366
4. 1.367
5.1.610
6. Nothing, just says one.

I hope I did it right.... I used the function with the diode symbol...

Here's my ohms test.

1. 0
2. 196.2K
3. 2.47K
4. 2.48K
5. 198.4K
6. 0

Did my test with a brand new copper-top 9volt battery.
 
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I'm so glad to hear you say that lol.

I have two CDI and one Coil coming in the mail(extra parts are good) since I'll be doing this forever once I get it going.

This explains the weak spark... It has a little something, but not quite enough.
 
When it comes to electronic parts testing with a multimeter isn't very reliable. Substituting is better.

Buy a CDI and magneto just in case.
 
rohmell said:
The resistance tests that you did on the coil look good, I think that part is OK, but it is always good to have spares.

Very sneaky trick, starting a new thread, to avoid exceeding you free 15 page limit. :)
Click to expand...

For spares, yes...saves on shipping in the long run. Gotta be savvy these days.
A moderator should take my thread and this one, merge them and clean up chatter and make a nice "Frustrations of a new China Girl owner and his determined goal to get the B'tch started/plus how to use a multimeter"

lol.

biknut said:
When it comes to electronic parts testing with a multimeter isn't very reliable. Substituting is better.

Buy a CDI and magneto just in case.
Click to expand...

I bought two CDI, one mag coil and a upgraded air filter from BFG(BoyGoFast)
I asked for a combined shipping, but I payed before that could be determined...crap...Shipping is expensive. I left BFG a note asking for combined shipping. Mayby he'll give me a return on the shipping.

Why doesn't Ebay have a cart option so you can add stuff and browse?

Spent over 17 dollars shipping on those items....
 
BGF has always combined shipping for me, sometimes I have got an alert in my email from paypal telling me that funds have been credited to my paypal account and each time it was BGF returning some of the shipping charge on multiple items I ordered.

Peace
 
mapbike said:
BGF has always combined shipping for me, sometimes I have got an alert in my email from paypal telling me that funds have been credited to my paypal account and each time it was BGF returning some of the shipping charge on multiple items I ordered.

Peace
Click to expand...


Yepp, he just refunded it to my PayPal like you just said.
That is cool.

Good place to buy from it seems....Stuff shoul dbe here tomorrow or the next day. I'll give it longer though.
 
I know we have people here that wont buy from BGF or some of the other venders out there ebay or not......, but I have never had a single complaint with BGF, he has always done exactly what he said he would and I feel he offers as good a deal as any and better than most.

Cant wait to hear that you and Dad are cruising around on that bike having a ball......

.wee.

Peace




Eric2.0 said:
Yepp, he just refunded it to my PayPal like you just said.
That is cool.

Good place to buy from it seems....Stuff shoul dbe here tomorrow or the next day. I'll give it longer though.
Click to expand...
 
eric:
my buss card says "parts - repair - installation" .... so i try to carry a few extra of the common parts.
several web sites you can get a CDI only for $9 add 4$ for the ignition wire.. i keep 3 or 4 on hand, along with a couple of MAG's
i also buy 7mm solid core wire and the standard auto bent clip and boot. it will screw into the CDI and you keep the plug clip on the end of the plug...

stay dry
gubba
 
rohill...
i know that you are aware of the following.... this is for the edification of the newer users...

at the factories they use 8 year olds and 80 year ods in the assembly line.there is NO quality controll to see if assembly is correct!
the first time you start the motor is the FIRST time it has run. they are not even spin tested---lol

i got a full kit once that did NOT have any bearrings in the clutch hub....
magneto wires that were ren and lavender on one.... lol

i have seen jugs that the molding seams were not removed or polished.... ran sizzling hot and a hard freeze at 1500 miles (8 miles from home)

clutch pads that were melted and stuck to the pressure plate.

you are buying a pig in a poke with these china girls, its luck of the draw. they are the cheapest made 2-strokes
available on the market.
BUT!!!!
you can replace the motor only for about $100 including shipping ..... you can replace 8 motors for the same price as one of the higher priced qualty made brands.
in the long run they are still the better value.

most of the break downs are improper break-in or runnung them at WOT from the first time started, trying to do wheelies, drag racing their friends, wrong fuel/gas mixture...owner abuse, etc

just my opinion of course....lol

stay dry
gubba
 
mapbike said:
I know we have people here that wont buy from BGF or some of the other venders out there ebay or not......, but I have never had a single complaint with BGF, he has always done exactly what he said he would and I feel he offers as good a deal as any and better than most.
Click to expand...
I thought I read that 2 of your 6? BGF motors blew up on you......maybe more.
2 out of 6? That is not good odds.
 
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gubba said:
rohill...
the first time you start the motor is the FIRST time it has run. they are not even spin tested---lol

just my opinion of course....lol

stay dry
gubba
Click to expand...
Your opinion is based on your limited experience.
for example Grubee Starfire GT 4's are started and run after assembly
and before they are packed.
I didn't see any 8 year olds in videos I have seen of some Chinese
bicycle motor "factories"
Gimme a link.....
 
I can vouch for the Starfire GT4. Mine was run, it smelled of gas and when I removed the head, the head, piston and spark plug were covered in black oily residue which I wiped off with a rag. The cylinder had a large amount of yellow oil covering it. The piston and cylinder were nicely chromed too.

Yes, I think they do mix 30W motor oil with their gas - laff

I have seen a lot of stuff here about how good the Starfire GT4's were and I have to admit being a little concerned about getting a motor that was 2 years old. but now I am very glad I did get a 2 year old GT4 from Nantong Jaili.
 
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