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tyst67
05-07-2014, 01:24 PM
What are some symptoms of the jets being too big and over fueling

89HST
05-07-2014, 02:31 PM
A blubbery lazy motor that four strokes. Much preferred and far cheaper than under jetting.

omcstratos
05-07-2014, 05:24 PM
If you can pull the head easily, you can look at your piston wash and jet accordingly.

MWhite
05-07-2014, 07:22 PM
What are some symptoms of the jets being too big and over fueling
Look at your plugs,, it will tell u if its burning rich, by the color of them, or if its jetted to high sometimes it will four stroke or what i call (dieseling) making a fluttering sound.

Fastjeff57
05-08-2014, 01:40 PM
If you are running gapless plugs, it's hard to tell what the motor is doing. I like them, but I stick ina set of conventional ones for jet testing. If they come out too black or too white you know it.

Slow Jeff

champ20B
05-08-2014, 05:57 PM
What are some symptoms of the jets being too big and over fueling

If the engine fails to smooth out @ full throttle ( running like a briggs lawnmower engine ) it is just too rich. Generally, for a racing engine (particularly rotary valve types) having it run a bit rough or rich at lower end or intermediate is preferred as long as it smooths out at high end. but when it comes to recreational-general purpose motors, economy is a popular choice. So the idea would be to get it just lean enough that the engine will accelerate smoothly and have strong top end as well. When you are at the point of smooth top end with a bit of rough rich running at intermediate speeds, you are close. Often, going the next size down will be the final fix as long as top end either improves or remains. If it (top end) is less, go back to the previous next bigger size and leave it.