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Discussion Starter #1
1975 Yamaha mikuni carb setting how many turns in and out on both adjustment screws? Does anybody know how to set these carbs up 388 mm Mikuni.
 

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I take it that this is on a GP292. Mikuni BN 8 butterfly carb.

Main Jet size #140
Pilot Jet Size #72.5
Pilot Air Screw 1 3/8 turns open
Idle Speed Screw 3/4 turns open
High Speed Screw 1 turn open

The pilot air screw is the one on the drivers left. On the right, the high speed is the top screw the idle speed the lower screw.
 

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Discussion Starter #3
I take it that this is on a GP292. Mikuni BN 8 butterfly carb.

Main Jet size #140
Pilot Jet Size #72.5
Pilot Air Screw 1 3/8 turns open
Idle Speed Screw 3/4 turns open
High Speed Screw 1 turn open

The pilot air screw is the one on the drivers left. On the right, the high speed is the top screw the idle speed the lower screw.
Thank you it's a 1975 338 FA with flat slide carbs 38mm Mikuni is the settings the same for this carb?
 

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No they are not. Are you sure the sled is a 1975 or that the carb is a Mikuni? Something isn't adding up.:dunno: What model number is the sled?
 

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Discussion Starter #5
The sled is modified for oval racing buddy bought it from the states it is a 338 yamaha it also has larger carbs than the originals he said they are flatslide mikunis 38 mm
 

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Unless someone here has experience with that modification, I guess you'll have to just play with it until you figure it out, Good Luck.
 
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