GY6 suggestions

[shootistpd27]

I have done all I think I can do to this point. My yerf would crank, and idle beautifully. But when you gave it any throttle it would act as if though it was drowning, or suffocating. Backfiring and all. I cleaned jets and carb but no fix. I adjusted the fuel air mixture with no result. Since they were so cheap, I replaced the carb. With no change. I thought that the new carb was jetted for a scooter so I replaced them with the cleaned old jets out of the old carb. No change. I even readjusted the air fuel mix and no change. I even tested the fuel enrichment valve on both the new and old carb and they were fine. MetalStud suggested adjusting the valves. I adjusted them to .003 and no change. I have now removed the shrowd and wiring harness looking for cracks or a vacuum leak. Do any of you have any tips for testing this out to see if there is a minor crack that I have not yet been able to see. I am at my wits end. It still idles wonderfully. I removed the exhaust completely to see if there might be an issue or stoppage in the muffler but no change except a whole lot of back fireing and it was LOUD. I am at my wits end and do not know what else to do. Please gentlemen, if you have any more suggestions, please fill me in. This motor is about to become my next target. I hit a clothes pin with a 308 at 150 yards but I am going to see how many times I can hit the gy6 at 25 yards with a 75 rnd drum mag. The wiring looks rough but good. The stator works. Lights work. I don't know what else to do. Thanks in advance for your help. And do you think if I replaced all of the gaskets on the engine if that would help, and if I did that, should I just go ahead and do an engine rebuild?

[x-bird]

to test for small intake cracks or leaks, have a propane torch on hand, (auggh! lol) fire the engine up and open up the torch's gas valve a little, aiming it around the intake area (but not into the fresh air feed). if the engine picks up speed, there's a leak. Same method works with carb cleaner and starting fluid. i prefer propane. otherwise i wonder if there's an ign timing issue.

[xlint89]

Have you tried a different CDI and/or coil?

Do you have the correct spark plug installed?

Is the plug gapped properly?

Did you check the carb's float level setting?

When you say drowning (rich = too much fuel) or suffocating (lean = lack of fuel), those are 2 seperate conditions. Is the spark plug wet? Or is it dry and sooty (black), or dry and white?

When you say backfiring, through the exhaust (I assume this since you say it was LOUD), or is it popping out the carb/intake?

[shootistpd27]

It backfires through the exhaust which doesn't sound too unusual when the rpms are dropping. It idles great. It is just that when I give it throttle it chokes out. I dont know what else it could be. I have just about given up and am about to just buy a new engine. Its 250 bucks and the time it would save me would be a lifesaver. What else can I doo. New carb, new battery, the new motor should fix it I hope. And one more thing. Where can I get the adapters for the four way lug pattern for the front wheels.? I have a great set of atv tires just waiting to be mounted and i hope that will cure most of my turning issues.

[xlint89]

Give it throttle, let it choke out, and remove the spark plug. What does it look like????


How about answering my other Q's????? If you want answers or suggestions, we need answers from you....

I'm not aware of any "adapters" for the bolt patterns. Usually you need to buy new hubs for the front.

What's the bolt pattern for the rims you have with the new tires?

[shootistpd27]

Originally Posted by xlint89

Give it throttle, let it choke out, and remove the spark plug. What does it look like????


How about answering my other Q's????? If you want answers or suggestions, we need answers from you....

I'm not aware of any "adapters" for the bolt patterns. Usually you need to buy new hubs for the front.

What's the bolt pattern for the rims you have with the new tires?

Several times the sparkplug was dark and black. I cleaned it up, did some adjusting and then it looked right in the middle. Today I took off the wireing harness in preparation for the crack check. I even took the airbox of. I used a tad of ether for a kickstart and it cranked up and for the first time with the throttle wide open, it kicked some butt. But when I let it idle down, the dang thing went dead and I couldn't get it started back. I am going to try and take a diesel engine heater hose with fram or air filter filler in side the hose and attatch it to the breather of the tiny carburator. I don't know where the leak is, or if there is a vacuum issue but I will try it again tomorrow.. The wheels have a four bolt pattern. I am pretty sure they will fit on the front and back of my trailmaster and they should fit the back of the spiderbox. But its just what i am going to have to do to get the fronts on the spiderbox working. If I can, which I doubt, I may just swap out the tires from the wheel

[GX150]

Most buggies use a 4/137mm rear bolt pattern while the Yerf uses a 4/110mm on the rear.

[xlint89]

Was your spark plug black (rich) after doing a Wide Open Throttle run? Or just idleing?

Plug reading while idleing is worthless.

What spark plug do you have in it? And what is it gapped at?

Have you tried spraying some ether (starting fluid) around the carb and intake manifold while idleing to find a possible intake leak?

As for the tires, you do know that there are different bolt hole sizes right? The Yerf Dog uses a 4 X 110 pattern on the rear. So, if your rims fit those, you then need new hubs on the front that have a 4 X 110 pattern like the ones Buggy Depot sells.

The stock front rims on the Yerf are only 6" rims, I highly doubt your tires will just swap out, unless the ones you want to use are for a 6" rim. What size is marked on the side wall?

[shootistpd27]

I took the wiring harness off, and after some......well.........wiggling and jiggling plus removing the air box, I will be danged if the dadgum thing started great. I had it jacked up with the rear wheels off the ground with the throttle wide open and it ran great. I started doing a little tweaking on the fuel air mixture when i found that the screw was missing but it was running fine. I replaced it and it ran fine for a couple of seconds and then started bogging down and finally it would not start. looks like i am going to have to go over it again. One thing that i am going to try to do is take a large heater hose, and an external air filter and customize it to fit and work better. I think this is one of those macheenZ that will make ghost symptoms as it runs better. I am sure the rear wheels will fit the four bolt pattern, but where will I get a four bolt pattern spacer for the front spindles with only the spindle and uninut.

[shootistpd27]

I GOT IT RUNNING, I GOT IT RUNNING I GOT IT RUNNIN, NANANANNAAABOOOBOOOO......... Man was this thing fast. My wife and I were flying. We had a blast. I figured that it would not be as fast as my daughter's trailmaster but this yerfy was hot to trot. We had a blast. However by the time I got home the left wheel bearing had gone out. I have decided to buy a crate motor from one of the recalls and do some fixing up. I thought that I found the crate motors pretty reasonable but now all I can find are the motors that have been kinda picked apart. I want one just to hook up, and drive. Thanks for all of your help.

[x-bird]

[satoys]

so what fixed it ?

[shootistpd27]

A wire was loose. I had to torque it down with more wire and krimp it. I actually had to leave the breather off. The air box would not allow it to run right, so I did a mod on the breather that didn't make a difference. With removing the breather ( and yes I know that is not a good thing) but dadgummit I was gonna ride it.

[satoys]

Can you post a picture of the fix? and maybe where the wire goes? I'd like to file this one away in case it ever happens to me in the future, I can look there first...