hi, just got into motorized biking, i love the concept and this site. ive looked on here for some help along the way. should have joined this site earlier because im in a mess of problems on my bike. i have skyhawk gt5 and its been a pain from the get go. first problem, I broke the screw flesh with the clutch arm. the clutch cable is really tight with no free play. anyways i ran into some problems with the garbage spark plug boot but i found an american replacement that seems to work very well. i cant start this thing no matter how hard a try. the engine is turning over and when i hold the spark plug to the fins and move the bike i see sparks. fuel is going to the carb. can lack of free play be the sole cause of not starting? I just grounded the engine on the rear mount, don't know if its a grounding issue. could it be the carb? can i get some solutions. should i try to remove this little screw, which might be impossible or go ahead and just buy a new clutch arm. this thing is really been a headache and im about to give up on it all together.
like the concept, need alot of help
- Thread starter dropleg
- Start date
Let's start from the beginning.
Which screw is broken? A sprocket cover screw? The screw that fits into the brass cable end? The nut that threads onto the tip of the clutch release cam (sticks out on the top of the sprocket cover)?
The cable is really tight you say. When you squeeze the clutch hand lever does the lever, cable, or release arm move at all?
Fuel going to the carburetor is a good thing, but it does not mean that fuel is going out of it at the correct air/ fuel ratio required to burn inside the combustion chamber.
Grounding a wire to the engine mount is strange.
There are only 4 wires of 2 colors to be concerned with.
Here's a diagram:
http://motorbicycling.com/attachments/f50/36243d1305772217-wiring-confused-wiring-diagram-9.jpg
Do not worry about connecting the kill switch for now. Just work on getting the engine to run first. You can always stop the engine by applying the bicycle's brakes when the engine is idling (clutch engaged) or by when the engine is idling, turning the choke on.
Which carburetor do you have?
Does it have a black round air cleaner, a red round air cleaner, or a pink square air cleaner?
Which screw is broken? A sprocket cover screw? The screw that fits into the brass cable end? The nut that threads onto the tip of the clutch release cam (sticks out on the top of the sprocket cover)?
The cable is really tight you say. When you squeeze the clutch hand lever does the lever, cable, or release arm move at all?
Fuel going to the carburetor is a good thing, but it does not mean that fuel is going out of it at the correct air/ fuel ratio required to burn inside the combustion chamber.
Grounding a wire to the engine mount is strange.
There are only 4 wires of 2 colors to be concerned with.
Here's a diagram:
http://motorbicycling.com/attachments/f50/36243d1305772217-wiring-confused-wiring-diagram-9.jpg
Do not worry about connecting the kill switch for now. Just work on getting the engine to run first. You can always stop the engine by applying the bicycle's brakes when the engine is idling (clutch engaged) or by when the engine is idling, turning the choke on.
Which carburetor do you have?
Does it have a black round air cleaner, a red round air cleaner, or a pink square air cleaner?
ok theres a screw on the end of the clutch arm used to hold the clutch wire down, it sits on top, at the very end of the arm, the clutch cable is tight and can no longer be adjusted because the bolt is broken off flesh with the arm. i can disengage and engage the clutch but im not sure if its fully in ganged, i hear the engine true over and air coming out of the muffler. i have no ground wires, but i have rubber where everything mounts to my bike, i went ahead and removed the rubber on the rear mount so the engine was metal to metal, not sure if it did anything. I took the kill switch off awhile ago, the white wire is capped off, not touching the frame. wires are blue to blue, black to black. i have the red square carb air filter clover, i dont see a primer button.
Step one, get rid of the factory plug in wire connectors. They are garbage and well known for poor electrical reliability.
Solder each connection and seal each with heat shrink tubing or at least electrical tape.
Second, I bet the carburetor is causing alot of your problems.
Read this thread for very good advice concerning it.
http://motorbicycling.com/f34/omg-i-have-tune-cns-help-30169.html
Also this thread may help you out too.
http://motorbicycling.com/f34/inside-2010-grubee-skyhawk-cns-carb-25062.html
Solder each connection and seal each with heat shrink tubing or at least electrical tape.
Second, I bet the carburetor is causing alot of your problems.
Read this thread for very good advice concerning it.
http://motorbicycling.com/f34/omg-i-have-tune-cns-help-30169.html
Also this thread may help you out too.
http://motorbicycling.com/f34/inside-2010-grubee-skyhawk-cns-carb-25062.html
If you can't get more slack in the clutch cable due to the adjuster bolt broken, cut the cable and remove from housing. China (Wal) Mart has a package of cables for around $6.00 in the bike section.
Highly recommended.
Highly recommended.
And, if you don't have a new cable stop or can't find one, go to a hobby shop that has model airplane accessories. Ask for 1/16" wheel collars. They usually come two or four to a package for a couple of bucks.
Tom
On the carb remove the rubber tube from the air vent to the bowl. This was EPA required and really screws things up. The jets on these carbs are known to not be seated properly and this can block fuel flow. Unscrew the bowl and you can see the jet to make sure it's not crooked or even missing.
so the wheel collar is suppose to fit on the end of the arm? sorry im not perfectly clear on what i should do with the wheel collars. the bolt can not be removed.
ok, i ordered a new arm and have a new cable from walmart, i think the lack of free play is the reason it does not start. Can i get any suggestions on this?
1. Install the new cable and clutch arm.
2. Adjust cable to have approximately 1/16" to 1/8" free play.
A general rule of thumb is if you can wiggle the release arm in the cover a little teeny bit without putting much effort into it then you should be good to go.
If it wobbles around and you can swing it back and forth a little then it is too loose.
If you can barely move it at all and it feels very solid and secure in the cover than it is too tight.
2. Adjust cable to have approximately 1/16" to 1/8" free play.
A general rule of thumb is if you can wiggle the release arm in the cover a little teeny bit without putting much effort into it then you should be good to go.
If it wobbles around and you can swing it back and forth a little then it is too loose.
If you can barely move it at all and it feels very solid and secure in the cover than it is too tight.
alright, i just got the engine to start, its a great feeling. Took alot of leg work but i got it started. problem, will not idle. I can drive it around and its fun, but it seems pretty slow. im sure its suppose to be faster. Can't get it to start every time. sometimes the carb overflows. I took the air filter off, dont know if i can start it with the filter on. Oh yeah the new clutch arm has not come in yet so keep that in mind
They all need tuning to get them to idle correctly.
They all seem slow and underpowered until they are broken in (about 200 miles).
Carb overflowing can be caused by numerous problems.
The 3 most common:
Not using an in line fuel filter will allow junk to get stuck inside the float needle valve and prevent it from sealing when the float bowl is full.
Float setting needs to be adjusted because it is too high, allowing the float bowl to overfill.
Float has a pinhole and is filling up with fuel turning it into a don't float.
They all seem slow and underpowered until they are broken in (about 200 miles).
Carb overflowing can be caused by numerous problems.
The 3 most common:
Not using an in line fuel filter will allow junk to get stuck inside the float needle valve and prevent it from sealing when the float bowl is full.
Float setting needs to be adjusted because it is too high, allowing the float bowl to overfill.
Float has a pinhole and is filling up with fuel turning it into a don't float.
ok i got a new spark plug and it seems to start everytime. was running pretty good and seemed to be going pretty fast. engine no longer seems to be flooding. lost my idle screw. now i really dont know what to do. i cant even figure out where i can get a new one. Im about to buy a new carb if i cant figure this out
ok, i just found that idle screw, i went walking down the road and found it in just a few mins. it seems to run better and better each time i run it. its alot of fun but i still cant get it to idle.
ok, i just found that idle screw, i went walking down the road and found it in just a few mins. it seems to run better and better each time i run it. its alot of fun but i still cant get it to idle.
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Well guys thanks for all your help. My clutch arm came in the mail and now i have more free play. bike starts every time and idles, now i just need to install the kill switch. I'm so glad this all worked out, there where many days when i just wanted to take a sledge to that bike.
generally problems come down to two things: compression or spark. If you followed the "instructions" given with the kit, that might have screwed you up pretty good, as that white wire isn't a ground but a power output from the magneto. Whn I built my first bike I had the same issue. And really you can just ignore that kill switch altogether, as they're crap and it's just as easy to brake and pull the clutch to kill the engine. All that switch does is short the circuit anyways and they're known to malfunction and cause problems with ignition.. I make it a habit (like many of us here) to give a good run through of the motor as a whole before taking it out on the road. A lot of these kits have crap gaskets made from tar paper and they can be DOA on arrival. Also there's a posibility that extra flash from the molding process is rattling around in that upper jug and that can kill the piston and sleeve pretty quick. Generally I get rid of the crap hardware (nuts and bolts) that are made of soft metal because you can over torque and strip them pretty quick. Sick Bike Parts has a kit for cheap that swaps out the jug bolts and engine mounts, and you can usually find the nuts @ your local hardware store. OH. And LOCTITE is your friend when it comes to mounting the motor and the Loctite blue is decent to use on the other nuts and bolts as things loosen with vibration pretty quickly. The clutch arm on these things are usually pretty stiff so I wouldn't think that would be the issue.. After you wire it all up unscrew the spark plug, leave it in it's boot and pedal while paying attention to the plug.. if it's not sparking you've got an electrical issue. If there is a spark then it might be a bad seal on the motor. I've had 3 or 4 instances of the lower jug seal being faulty and losing compression through a pinhole leak.