OTP
New Member
Ive got a new Grubee Skyhawk GT5A that runs too rich. Since I live on the side of a mountain and weigh 250 pounds, I bought a hub adapter and 50 tooth sprocket from MZMIAMI parts to go on my 700c wheel. I broke the engine in on the 1/4 mile of reasonably flat dirt road by house with the recommended 16:1 mix. What a dripping mess. It was 4 stroking terribly with the stock 70 jet so I ordered a 68 and a 66 from SBP.
I put the 68 jet in my NT carb and took off on a 60 mile ride still with the 16:1 gas. I was able to climb pretty big hills that I never would have been able to without the engine's help but it was still 4 stroking on anything but an uphill grade.
Now I've got the 66 jet installed and I'm running 32:1 mix but it's still not running right until I have a pretty good load on it going up hill. By the time it starts running right, I've lost most of my momentum.
I've read the hell out of these forums and have gone over everything I could think of. Float is correct, there are no settings on the needle, everything is tight, running NGK B7HS plug, I even poked a long screw driver through the mesh screen inside the muffler in an attempt to increase the airflow. That seemed to help a little but the thing is still getting too much fuel.
I don't want to go fast, I just want the engine to run as it should. Is it safe to go smaller than a 66 jet? Is it possible the thing is geared too low and doesn't have enough load on it with the 50 tooth sprocket? I'm considering trying the stock sprocket just to see what happens.
I put the 68 jet in my NT carb and took off on a 60 mile ride still with the 16:1 gas. I was able to climb pretty big hills that I never would have been able to without the engine's help but it was still 4 stroking on anything but an uphill grade.
Now I've got the 66 jet installed and I'm running 32:1 mix but it's still not running right until I have a pretty good load on it going up hill. By the time it starts running right, I've lost most of my momentum.
I've read the hell out of these forums and have gone over everything I could think of. Float is correct, there are no settings on the needle, everything is tight, running NGK B7HS plug, I even poked a long screw driver through the mesh screen inside the muffler in an attempt to increase the airflow. That seemed to help a little but the thing is still getting too much fuel.
I don't want to go fast, I just want the engine to run as it should. Is it safe to go smaller than a 66 jet? Is it possible the thing is geared too low and doesn't have enough load on it with the 50 tooth sprocket? I'm considering trying the stock sprocket just to see what happens.
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