engine problems..can anyone help

R

ridenbigyall04

New Member
i just installed a 66cc grubee skyhawk motor on my bike. i installed everything as i was instructed to in the manual. i put gas and oil mix and it wont start all it does is bogg down..someone help PLEASE im getting frustrated
 
You say it won't start and then say it boggs down???? It can't bog down if it didn't start.
what fuel mix did you use?
16 to 1......? too much oil but it should start up and run should be ok to use it up then go to a mix of 24 to1 or 32 to 1. If you go with a syn oil then 40 to1 will be ok.
You know which way to put the choke lever?Lever up to choke and lever down for normal running.
Spark plug gap? 0.017 to 0.024 is good 0.035 too much spark plug gap. A lot of people say to ditch the stock china plug not me they work ok.
Did you check the carb before you installed it making sure the inside parts were in place and tight
the long brass tube with the main jet on its end is known for not being tight sometime its not even screwed in and laying in the float bowl.
The fuel inlet nipple on the carb usually needs to be tightened as they are also loose it should not cause much more than a slight fuel leak but it can cause the float needle seat to leak some.
Stock setting for the throttle slide needle is #2 notch from the fat or top of the needle.
The idle speed screw only adjusts the idle speed and has no effect on fuel/air mixture. I told you that just so you will know.
You can also look at some of my posts boring as they are but you might be able to figure out some of your problems if you will look at them. Check over your bike and look at some of the thing I suggested let me know what you find out. Take some time to describe just what is going on with your engine I'll try to help you out. Don't just start trying a bunch of things at once try one thing then see what the change did.
Norman
 
do you have a good spark? pull the plug and spin the engine over while watching the spark plug.
you a first time builder? Do you know anything about how an engine works?
Your first post said it was bogging down? Did you ever get it to run?
 
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I just had my motor stop on me because I put oil in first then petrol and the carb filled with oil ( silly me ) . Just a posibility try draining the carb and tank.
 
yea im a first time builder i bought the bike from someone else that already hasd a motor on it...i just bought a new motor the bike was already set up. i drained my carb and emptied my tank and tried the 32:1 but still no start...i checked to see if i was getting a spark and there is no spark...the cdi box is brand new....what are some recomendations to fix this problem cause i have old cdi box and that doesnt work either :-||
 
You should have 3 wires coming out of the magneto coil one white, one blue, and one black.
If your not using lights tape off the white wire. The blue wire goes from the magneto coil to the blue wire on the cdi.
The black wire is a ground wire. It's attached to the magneto coils frame under one of the screws that hold the magneto coil on the engine. This wire attaches to the cdi's black wire.
sometimes the connections fail they will look ok but still be no good. you can either install new connectors or even solder the wire together and not use connectors, but then you will have to cut the wire if you need to remove these components.
Or crimp the connectors and solder the crimped area for a better solid connection.
 
Not to "hijack" the thread, but Norman... you seem to be the "go to guy" for the electrics from my reading. I see you saying to tape off the white wire... couldn't it be used along with the blue wire to feed the CDI unit?

Just wondering...
 
Don't panic just yet.
Try a different spark plug first.
Also, if the white wire isn't connected to anything, ensure that it's not touching ground.
In fact, even if the white wire is connected to your kill switch, temporarily disconnect it and see if that helps.

Do you have a DMM, (multimeter)?
 
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yes i have a dmm.... i tried a different spark plug....and the dmm showed a good connection on all the wires i stilldont see a spark and the bike wont fire...does it have to be goin a certain speed to see a spark?
 
You'll need to give the wheel a pretty good spin to see spark.

The reason that I asked if you have a DMM wasn't to test for continuity, but now that you mention it, how did you test the connections?

The real reason was so that you can test continuity of the magneto coil. Set the DMM to 1K or 2K resistance range, then test between the blue and black wires. (Disconnect the blue wire from the CDI unit to do this.) I forget the exact value, but it should be less than about 300 ohms. If it measures infinite or high resistance, that will be the problem.

What plug are you using? If not an NGKB6HS, go and get one.
 
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ridenbig..take th cover off the magneto and check your wires.see if the two soidered wires are on properly and the ground is screwed on tight...there is only 3 points...magneto...cdi...kill switch...blue to blue...blk to blk...white can be taped off...wiring is important...cdi can be bad out of box...kill switch can be bad...wires are thin and sometimes fragil...be patient and take your time...if you use the plugin fitting...silicone the fitting after its plugged in...well thats enough for now...good luck...dennis...are you getting gas....pedal the bike and try and start it...than check your plug...if its wet...its getting gas...
 
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regarding teh healthy spin, remove plug, hook to plug wire, then spin, se then. ALSO do you have access to another coil. also as one said, MAKE SURE the white wire is NOT touching metal., also take your meter, hook, one lead to one wire, the other lead to the other. note reading, then while connected, hit button, see/note changes
 
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