Adjusting the stock NT carburetor on my 2 stroke 70 cc Thatsdax engine has been one of the most frustrating experiences. When I was using the stock exhaust, I downsized the jet from the stock .70 mm size to a .66 mm jet. I picked up a few mph and on acceleration I was 2 stroking more.
Recently however, I added an expansion chamber. This caused my engine to run really rich with the .66 mm jet. Unburnt oil sludge was actually dripping out of the exhaust. I then installed a .64 mm jet and my plug went from dark black and wet to a drier black color. Oil is still dripping out of the exhaust, but not as badly now lol.
I have my e-clip on the highest setting so while accelerating, my engine 2 strokes consistently. However, once I reach cruising speed and load is taken off of the engine, it starts to 4 stroke constantly.
Should I downsize again to a .62 mm jet on move my e-clip down a notch or two? It seems like this might be on the small side for a 70cc engine!
Thanks!
Recently however, I added an expansion chamber. This caused my engine to run really rich with the .66 mm jet. Unburnt oil sludge was actually dripping out of the exhaust. I then installed a .64 mm jet and my plug went from dark black and wet to a drier black color. Oil is still dripping out of the exhaust, but not as badly now lol.
I have my e-clip on the highest setting so while accelerating, my engine 2 strokes consistently. However, once I reach cruising speed and load is taken off of the engine, it starts to 4 stroke constantly.
Should I downsize again to a .62 mm jet on move my e-clip down a notch or two? It seems like this might be on the small side for a 70cc engine!
Thanks!