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79 3H3. Carburettor main nozzle (aka. emulsion tube / needle jet)
Hi from UK
I've tried a few Facebook sites, with limited success to resolve this issue .....
The Parts List for 1979 Eleven Special 3H3 shows 2 different main nozzles as photo (Yamaha description), ie. 2 pairs
One pair for outer carbs 1 & 4: part no: 2H7-14941-02
One pair for inner carbs 2 & 3: part no: 3H3-14941-02
So one pair has 16 cross-drilled holes, and the other pair 12 (maybe 10). It's not clear in the book how many holes each type had.
My operation assumption is:
The fuel (gas) goes up the tube via the main jet, while air whistles in via the cross-drilled holes to emulsify the fuel (the holes are well above fuel level)
So, my question is.... do the ones with more holes go in carbs 2&3 (i.e. let more air mix with fuel to give a cooler burn for the middle cylinders), or not.
All opinions advice welcome?
thanks
I've tried a few Facebook sites, with limited success to resolve this issue .....
The Parts List for 1979 Eleven Special 3H3 shows 2 different main nozzles as photo (Yamaha description), ie. 2 pairs
One pair for outer carbs 1 & 4: part no: 2H7-14941-02
One pair for inner carbs 2 & 3: part no: 3H3-14941-02
So one pair has 16 cross-drilled holes, and the other pair 12 (maybe 10). It's not clear in the book how many holes each type had.
My operation assumption is:
The fuel (gas) goes up the tube via the main jet, while air whistles in via the cross-drilled holes to emulsify the fuel (the holes are well above fuel level)
So, my question is.... do the ones with more holes go in carbs 2&3 (i.e. let more air mix with fuel to give a cooler burn for the middle cylinders), or not.
All opinions advice welcome?
thanks
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