KeelHauler
New Member
Like I said in my intro post, I would like start off by thanking all of you for the wealth of knowledge that is here. Thanks to you all I decided to give the whole motorized bicycle thing a try. Originally I was looking to buy a moped but realized that it would be near impossible to find a good moped for less than $500, so I decided to build my own! I purchased a 50cc Chinese (HT) kit off of eBay for $100, and paired it with a Schwinn bike I got from Target. It took a few nights to get the bike all but together, but I finally got it running. And it felt great! I made sure to take it nice and easy since it was still being broken in, and rode it around for about 3 miles. After the ride I put it all away in my garage and hoped for many more enjoyable miles.
Now is where the trouble starts.
I came back to the bike a few hours later, and just could not get it started. After a few failed attempts, and a few too many pushes of the plunger, I noticed fuel was dripping out from the carb filter, so I just figured it was flooded and waited until the morning. The next morning, still nothing. Skip forward about a week, and I still couldn't get it running.
I've replaced the spark plug with an NGK B6HS, replaced the boot with an NGK boot, and replaced the spark plug cable with some better wire from Napa. Bike still wouldn't start. If I pull the plug out of the head and pedal, I get a spark, although it seems to be weak. I've tested the plug with a range of gaps from .015 to .030, none seem to get a start.
I've pulled off the clutch cover, readjusted the clutch cable. If I have the spark plug out I can see the cylinder moving when the clutch is released, and I can only assume it is when the spark plug is in.
I've tested the magneto to see if there is a short, and there is not. I am also getting a charge from it when I pedal the bike. The wires coming from the magneto have a secure connection to the CDI.
There is not and has never been a kill-switch installed, and the white wire from the magneto has been taped to prevent a short.
The carb has been disassembled, and it is totally clean. I can see that the throttle cable is actually moving the plunger in the carb when I pull the screen/filter off, and have tried starting with all different combinations of throttle positions.
I am running the fuel/oil ratio at 24:1 after having seen that recommended on this site. I installed an inline fuel filter rather than the piece of junk that came with the kit, and there are no air bubbles in the line like other people have had.
I tried giving a spray of WD-40 into the cylinder before trying to start, still didn't start. Same when I tried a little ether in there. Even tried some RC car fuel. Nothing.
Pulled the head, and the cylinder and piston still looked good. Pulled the exhaust, rings still looked new. Same with when I pulled the intake manifold. The only thing I noted when I pulled the head was that there was no head gasket. I don't see how this could cause it to not run now seeing as it ran fine before just as it is. I have also read elsewhere on this site that other members have been able to run without a gasket. Also, I can't hear any air leaking out of the head when I am trying to start the bike.
It's been about 85 degrees or so outside when I am trying all of this, so it's not like the engine is cold.
I've tried starting at all different speeds, with all different positions of both the clutch and the fuel air mixture. Nothing works.
I'm sure I am getting compression, because if I am rolling the bike along and I let out the clutch, there is a noticeable drag on the bike.
Well there you have it. I'm sorry it is such a long post, but I am at my wit's end trying to get this thing running again. I've done quite a bit of searching on here, and I believe I have tried just about everything I can.
Now is where the trouble starts.
I came back to the bike a few hours later, and just could not get it started. After a few failed attempts, and a few too many pushes of the plunger, I noticed fuel was dripping out from the carb filter, so I just figured it was flooded and waited until the morning. The next morning, still nothing. Skip forward about a week, and I still couldn't get it running.
I've replaced the spark plug with an NGK B6HS, replaced the boot with an NGK boot, and replaced the spark plug cable with some better wire from Napa. Bike still wouldn't start. If I pull the plug out of the head and pedal, I get a spark, although it seems to be weak. I've tested the plug with a range of gaps from .015 to .030, none seem to get a start.
I've pulled off the clutch cover, readjusted the clutch cable. If I have the spark plug out I can see the cylinder moving when the clutch is released, and I can only assume it is when the spark plug is in.
I've tested the magneto to see if there is a short, and there is not. I am also getting a charge from it when I pedal the bike. The wires coming from the magneto have a secure connection to the CDI.
There is not and has never been a kill-switch installed, and the white wire from the magneto has been taped to prevent a short.
The carb has been disassembled, and it is totally clean. I can see that the throttle cable is actually moving the plunger in the carb when I pull the screen/filter off, and have tried starting with all different combinations of throttle positions.
I am running the fuel/oil ratio at 24:1 after having seen that recommended on this site. I installed an inline fuel filter rather than the piece of junk that came with the kit, and there are no air bubbles in the line like other people have had.
I tried giving a spray of WD-40 into the cylinder before trying to start, still didn't start. Same when I tried a little ether in there. Even tried some RC car fuel. Nothing.
Pulled the head, and the cylinder and piston still looked good. Pulled the exhaust, rings still looked new. Same with when I pulled the intake manifold. The only thing I noted when I pulled the head was that there was no head gasket. I don't see how this could cause it to not run now seeing as it ran fine before just as it is. I have also read elsewhere on this site that other members have been able to run without a gasket. Also, I can't hear any air leaking out of the head when I am trying to start the bike.
It's been about 85 degrees or so outside when I am trying all of this, so it's not like the engine is cold.
I've tried starting at all different speeds, with all different positions of both the clutch and the fuel air mixture. Nothing works.
I'm sure I am getting compression, because if I am rolling the bike along and I let out the clutch, there is a noticeable drag on the bike.
Well there you have it. I'm sorry it is such a long post, but I am at my wit's end trying to get this thing running again. I've done quite a bit of searching on here, and I believe I have tried just about everything I can.
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