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Post by jerimiah on Sept 22, 2017 13:17:14 GMT -6
I have a 49cc gy6 scooter 2008 Eagle. The front left fork tube is leaking. I went online to purchase a rebuild kit and only found replacement fork tubes that were very inexpensive. The ones I found have a slightly different dimension. Mine is 26mm upper tube, theirs is 26mm. Mine is 45mm between center lines of the brake caliper mounting bolts, theirs is 45mm. Mine is 10mm axle bolt hole, theirs is 10mm......Mine is 412.75mm extended length from the bottom of the upper bolt in the upper tube to the center line of the 10mm axle hole (I measured this with the kick stand on and front wheel in the air), theirs is 380mm. That is a difference of 32.75mm (aprx 1.3 inches). I looked all over the internet and for the rest of the specs to match this is the only length available. I am wondering if I install this will there be a problem or a difference in the ride?? Could mine have gotten longer because of wear?
Also, mine has only a dust cover where the upper tube comes out of the lower fork tube. The new one has a bellowed boot. Should that be a problem?
Any help is appreciated, thanks.
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Post by jerimiah on Oct 18, 2014 16:14:45 GMT -6
Hard to find a diagram for that, but it has to be ball bearing to close off the outlet and then the spring on the jet. So when the plunger is pushed down it creates pressure on the ball bearing allowing fuel to come out and then the spring closes it again. So taking the Fuel ratio pic as an example the pumper jet you would have 4=jet,3=spring,2=ball bearing. Alleyoop Thanks for all the help Alleyoop. I put the carb back together and it runs great after making adjustments. I have another question in trying to understand how everything works on this scooter. There are 2 vacuum lines coming off the intake manifold, one goes to the gas pecock and the second vacuum line comes off the intake manifold and goes to what looks like a vacuum switch, which is not on the carb but near and mounted to the frame. The vacuum opens and closes a larger hose. One side of the larger hose goes onto a metal pipe that is mounted with 2 screws into the engine just below the valve cover.(Almost looks similar to the exhaust manifold). The other side of the larger hose extends to nowhere and has a black plastic small diameter canister type thing on the end of it. Pulling off the canister thing I cannot see through it but can easily blow air through it each way. It almost looks like a fuel filter. When the motor is running and creating vacuum the vacuum switch connects both sides of the larger hose and I can feel air coming out of the plastic canister side of the hose. Is this just an emission breather pipe from the crankcase? or?? Thanks |
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Post by jerimiah on Oct 15, 2014 12:55:55 GMT -6
You will see the indentation where the ball goes, the spring is to extend the plunger out again. As far as the Fuel Ratio Screw is concerned, look inside you MAY be able to see the tiny washer and behind it the rubber O-Ring. When you take out the screw only the spring will usually come out you have to bang it in your hand for the tiny washer and O-Ring to fall out. On some you have to get a tiny wire and pick them out. Alleyoop  Thanks, I found the washer and o ring. As far as the accelerator pump, I am familiar with the diaphram and the rod and the spring assembly. What I am talking about is where the gas is pumped from that diaghram. Next to that assembly on the inside of the bottom bowl of the carb is a brass jet, which when unscrewed has a spring and a ball bearing, and my question is about that. |
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Post by jerimiah on Oct 15, 2014 10:33:37 GMT -6
I have a used 50cc chinese scooter. I took apart the CVK carb to clean. when I removed the brass jet for the accelerator pump, in the bottom bowl housing of the carb, behind it was a tiny spring and then a tiny ball bearing. After cleaning I filled the bowl with fuel and worked the rod of the accelerator pump and fuel squirted out a tiny machined hole in the bottom of the bowl instead out of the brass jet in the bowl. When I put my finger over the tiny hole then some fuel comes out of the brass jet. Shouldn't the fuel be coming thru the brass jet all the time?? and...is the ball a check valve for that to happen..Wondering if maybe the spring should go in first and then the ball (maybe assembled wrong before I got it)? Also the air fuel mixture screw has a spring, should it have a o ring and or washer on the carb side of the spring??? Any Diagram showing the ball and spring? Thanks for any help.
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Post by jerimiah on Aug 1, 2014 9:04:18 GMT -6
AC has Phase (back and forth) and Neutral (not moving). DC has Positive (Flowing this way) and Negative (flowing that way). Nether of these has a GROUND component. AC has 3 wires. 2 of them are active. DC has 2 wires both active. But neither one has GROUND. GROUND is for safety purposes. Circuits do not need a ground to work, they just need to connect back to themselves thru the load. Ground is to make the circuit safe to handle for mere mortals. So you can ground them both together because NEITHER one has a ground as PART of it or it's natural circuit. I'm going to take Bash and put him on this PC board. His job is to run back and forth pushing a button on each side. (Yellow man) I'm going to put Alley on the other side and his job is to run around the circle and spin the star at every lap. (Blue man) They are both on the same PC board but they are both separate. If I happen to touch either one then I am adding myself into the circuit and the juice will flow into me, ESPECIALLY if I am GROUNDED. So, I am going to add a line to each one that makes the whole thing safer for me to touch. I am going to ground each one to the dark reddish brown box (representing the Earth) Now, they are grounded so if I happen to touch them the juice will not flow directly into and thru me. It now flows into the GROUND where it is harmlessly dispersed. The GROUND is the trash can of the circuit not a vital component. Understand?  Thank you Bashan and Guitarman and Alleyoop for the time and effort to explain this. Guitarman I still have some confusion about your last explanation about ground. In DC there are 2 wires and the frame of the scooter is being used as one of those wires. I understand that a ground is not necessary for ac or dc to work but it seems like the scooter frame is being used as the negative wire and ground. It seems like the AC on the scooter is also using the scooter frame as one of the wires. So my confusion is still in how they can both share the same wire?? |
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Post by jerimiah on Jul 31, 2014 8:43:18 GMT -6
Let's take an 8 coil stator that is your standard G-Y-W single phase. One of the coils is a seperate mini system that supplies the CDI with AC current. It's the one that's all wrapped up in itelf (red arrow}. 
The white wire starts at one end of all of the other coils and snakes around to terminate at the ground wire (green arrow). I know it doesn't look like the white does that but it's a rather circuitous route that doubles back. Believe me, I traced it out, that's how bored I was one winter day.  But here's the important part of the answer to your question, the yellow wire taps onto the center of the white wire, the so called center tap. Since it is tapping into the middle of the white wire it makes much less energy because of fewer coils. This is a very simplified diagram to illustrate the configuration:
Look inside the rectifier/regulator, there's a square that is actually a bridge rectifier. You see the white runs directly to one side of the bridge. The yellow however splits off but is regulated to 12v AC inside the R/R. the split is what gives us the yellow with 12v AC to supply the lights. Since the white runs directly to the bridge and doesn't split it is considered "dedicated" to the charging circuit. They never go anywhere without the other one....ba-dump. You can see the red coming off of the bridge and running to the battery with 12v DC and also supplying DC circuits such as lights and the starting circuit..
Thw white and yellow are two sides of the feeds to the R/R. You can think of them in a balance and they push each other back and forth...so to speak. A bigger draw on one pulls from the other. You can do this to some degree and the other circuits within the R/R will compensate. But you can push it too far and roast your R/R. I ran a scooter entirely off of the battery one summer and didn't use the yellow at all. The R/R got kinda hot but it lived to rectify another day. I don't recommend shifting too much one way or the other on an R/R however. But what you're doing with just a couple lights won't hurt a thing. And yes, different scooters have different configurations of what the yellow does. By the way, the wiring diagrams are a joke, they are never right. Your bike is from the bowels of China my friend, it is a different world. Your configuration is fine, the "split" is within acceptable parameters. Also, I think your bike was rewired hence the AC tail light. Did I answer all of your questions? If not ask away. Rich Thank you Rich for all the info and explanation and pictures of how the system works. As far as the bike being rewired I am not sure. Right now the tail light works off of the ac and the brake light works off of dc and it is one bulb. Do you think I should rewire it so that the tail and brake work off of dc. I do see an advantage to the tail working off of the ac so that if the battery is dead at night you still have tail light. Also, I have worked on a lot of electrical on dc cars and am confused about a common ground for the ac and dc system. Is this normal in motor scooters? Another question in understanding the stator and rectifier you explained and posted a great wiring diagram. I understand that the white wire from the stator goes into the rectifier at a high ac voltage and then comes out of the rectifier as a red wire, 12-14 vdc, to charge the battery. I am not understanding how the yellow wire ac voltage is kept down to 12-14vac by the rectifier. The yellow wire (according to your diagram) is t'd off from before it reaches the rectifier and feeds the lights. So I don't understand how the rectifier is able to regulate the ac voltage in the yellow wire. I am imagining that the yellow wire would need to go into the rectifier as high ac voltage and have a wire coming out as lower ac voltage Similar to the white going in high and coming out as red coming out low. |
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Post by jerimiah on Jul 27, 2014 1:03:59 GMT -6
The Big Guy is 100% spot on. The brown wire is DC 12v. Yellow is AC 12v and energizes with the stator. Running just the tail and dash as an extra load will not hurt anything, I've did it. In fact I've ran all of the lights off of the yellow and used the white as charging and it worked fine. We can try to find the brown and hook it back up but you'll have to pull some plastic. You actually run into problems when you try to run a single phase G-Y-W stator while using just the yellow or white as the energy source. It's designed to split the load. You will be fine using the yellow as you are, ride on.
This is a generic diagram, not specific for your bike. Note the brown to the back which is actually the black. Sometimes the black runs to the front and sometimes the brown does. The brown always runs to the back.
Thanks for the info and wiring diag. Seems like different scootesr have a different accessories running 12vdc and 12vac. I had a bad battery up till a week ago so it was obvious what was run from the stator 12vac. On my scooter the headlight (high and low beam), and tail light and illumination dash light is 12vac. Now I have a good battery and new rectifier so I can just turn on the ignition without motor running and use the 12vdc to run the blinkers, horn and brake light. It doesn't seem like the 12vdc is running much compared to the 12vac. You mention that you need to split the load between the ac and dc, does it seem like there is any problem in how mine is splitting the ac and dc load?? Also it seems like the black wire coming from the ignition, according to the above diagram, is being fed by the battery 12vdc which then feeds the brown wire which feeds the tail light. But seems like my tail light was running off the stator? Any thoughts are appreciated. |
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Post by jerimiah on Jul 26, 2014 19:12:33 GMT -6
I have a 49cc 2007 chinese scooter and the tail light stopped working last night also the dash board illumination light stopped same time. Both bulbs work.The brake light works fine. There are 2 elements in the same brake/tail light bulb. Before the tail light stopped it would run off the stator electricity and the brake light would run off the battery. I checked the wiring diagram on line but my colors are different. I found a plug at right rear of scooter that feeds the harness going to the rear light assembly. The brown wire in the plug goes to the tail light and so does a brown wire go to the illumination bulb socket on the dash. After looking at wiring diagrams that aren't exactly like mine I see that the yellow wire usually feeds the tail light.... so I jumped from a yellow wire that was in a socket that was not used by the scooter to the brown wire going to the tail light bulb. Now when the scooter is running the tail light works and the dash light works. I have no idea where the brown wire is suppose to get it's positive from as I checked all plugs for continuity that had a brown wire in rear and front. Do you think I will hurt the electrical system the way I fixed it? Does anyone know how and where that brown wire is suppose to get it's electricity?
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Post by jerimiah on Jul 23, 2014 14:46:51 GMT -6
Thanks for the info. I ran the tests again as you asked and everything was ok except for the red charging wire going from rectifier to battery. I ordered the rectifier on ebay and should be here Friday. From the picture on ebay it looked identical physically to the 4 wire one I have now and I thought I could just plug the new one in and good to go. I have been reading that sometimes replacement rectifiers are wired differently and it might not be compatable with my scooter plug wiring. So.... what to do to figure this out. If I plug it in and it's not like the old rectifier can I hurt the new rectifier or my scooter. Is there a way to figure out the prongs on the new rectifier? The old rectifier I have now is wired like this: Looking at the rectifier's plug with the plastic nub ( the plastic piece that protrudes out of one side of the plug that is used to lock the scooter's side of the plug in place) on the bottom of plug: top left is Green, Top right is white, Bottom left is yellow, bottom right is red. Another big question I have is about how the ac/dc system actually works together. From what I have read from your post and others online I understand that the white wire is being fed ac voltage from the stator and so is the yellow wire. With my bad battery, which even when charged was only about 4v, the headlights and tail light and brake light worked, which must have been from the ac being generated. When I tried to use the blinkers I would just get a buzzing noise from the blinker relay because not enough juice to run the blinkers. Now I have a new battery that is slowly running down because it is not charging. I am confused about the dc and ac votage. My headlights, tail and brake lights were working off the ac voltage, but when I look at the bulb it says 12v dc. The same for the all the bulbs on the scooter including the blinkers. Can these bulbs run on ac and dc, and when the bike is at higher rpm isn't the ac voltage much higher than 12volts. Is the ac and dc running through the wires at the same time?  1. Test the stator in series, that is one probe in a supply wire and ground the other
2: Unplug the stator connector. Set your multi to AC voltage (up to 100v AC if not an auto ranger) and ground one probe IN THE STATOR GREEN CONNECTOR OF THE PIGTAIL. Do not ground it to the frame to avoid interference. Put the other probe in white wire and start the engine. Give it some RPM and you may get up to 60v AC or even a little more. Down to 40 would be acceptable.
3: Same procedure for the yellow wire, it should be a little less. If the voltages aren't within these ranges your stator is bad. Plug the stator back in.
4: If the stator voltages are good start on the R/R. Leave the R/R PLUGGED IN. Set your multi to AC low volts, no more than 50. Ground one probe to the R/R green to avoid interference. Test the yellow wire, you should get 10 to 13 v AC depending on RPM and what lights are on.
5: Test the white wire the same way, up to 15v AC is acceptable, less than 12 suspect.
6: Test the battery terminals set at DC with some RPM, 13 to 14.75v DC is acceptable. Anything outside of the above parameters is a bad R/R.
The G/Y/W single phase GY6 stator uses one long white wire through the stator to generate AC voltage dedicated for the charging circuit. About halfway along the wire a yellow wire taps into the center of the white and is used for AC to drive the headlights etc. That's why there's two wires that are both AC.
Now Alley is 100% correct, by not using the battery you were forcing the current through the yellow and the R/R will take some of this but soon poof. Even if you have the battery hooked up, if it gets bad enough it actually becomes a resistor and starts refusing to let electrons through especially if a plate shorts out. Make sure you test the stator like I outlined above, your results from your testing were a little screwy but I agree with Alley it's probably your R/R which it usually is.
Your blinkers quit working and then started back working because they are DC and run off of the battery. So the AC voltage coming from the yellow never made it to the blinkers, or dash lights, or tail lights, or any of the other DC DOT mandated lights. So you may want to run through the tests again to make sure you did it right and then check with us before you order parts. Rich
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Post by jerimiah on Jul 21, 2014 20:44:15 GMT -6
I acquired a basket case 49cc chinese scooter. It runs good now after working on it and replacing some parts. The main electrical part I replaced was the cdi. The battery in it was bad so I have been kick starting it and using the bike with no problem, except the blinkers would not have enough electricity to work although the headlight stays on all the time with no problem. Today I put in a new battery and everything works great including the blinkers and horn, except I checked if the battery was charging and it is not. With engine off battery read 12.25v and with engine started and high rpm does not increase. I checked at the back of bike and unplugged the wires coming from the stator. I checked the yellow and the white wire and used the green for ground for the vom meter. At idle both wires read 13-16 vac and at really high rpm 105 vac. Shut motor and I plugged the connector from the stator back in. I pulled the plug in the front on the rectifier and tested the red fused wire coming from the battery and it was 12.25v. Started the scooter and tested the white and yellow wires at rectifier plug and got same readings as the plug at the back of the scooter. I pulled the fuse on the red wire going from the battery to the rectifier plug and plugged the plug back into the rectifier. I took a volt reading on the red wire coming from the rectifier to the fuse and got at idle 5v dc and at very high rpm 9v. Then I changed the meter to 10amps dc and put the test wires between the place where the fuse is removed, on the red wire coming from the rectifier to the battery, and it read 1.4 amps at idle and at high rpm. I am trying to figure out why I am not getting the 12 to 14 volts dc that should be going to the battery. Can the rectifier go bad so it only sends lower voltage, things I read say that usually if it goes bad the volts get too high? Could it be the stator?? Also.... why are there 2 wires, yellow and white bringing ac voltage from the stator to the rectifier? Is there a way to check the rectifier? Am I getting enough ac volts to the rectifier? Any help is appreciated. Read more: 49ccscoot.proboards.com/thread/9588/charging-problem#ixzz389jPOSXd |
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But here's the important part of the answer to your question, the yellow wire taps onto the center of the white wire, the so called center tap. Since it is tapping into the middle of the white wire it makes much less energy because of fewer coils. This is a very simplified diagram to illustrate the configuration:
