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Carb jet size

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Murf:
I am sure this has been asked loads of time but I have looked through search and can’t find anything exactly like I have.

I am rebuilding Keihin carbs from 75 550K1, the main jets that are fitted are
No 1 115,
No 2 115,
No 3 100,
No 4 100,
Now obviously this isn’t right but for this bike it’s par for the course, nothing surprises me anymore.  However could there be any reason for it??? Apart from POs being dicks. Or maybe living at the top of an enormous hill and using it as a way to compensate for atmospheric pressure changes when going to the bottom for groceries 😄.

The parts book lists size as 98
So I would think the 100s are ok
What size is considered correct these days with modern fuels.

The slow jets are 38 as listed.

For No 2
Slide stamped 2.5  03
Needle number 27304  clip in second to bottom grove ie needle high.
Haven’t done the others yet will look at them tomorrow

Nurse Julie:
It could have been to compensate for altitude but it's a strange way of doing it. More importantly, are the jets genuine Keihin, with the stylised K logo stamped on them or are they aftermarket? 98's and 38's are standard.

McCabe-Thiele (Ted):
There is chart on the subject iirc not sure if K2-K6 posted it.

I found my copy it's an old PDF document with some errors I believe.

deltarider:

--- Quote from: Nurse Julie on November 11, 2024, 09:15:49 PM ---It could have been to but it's a strange way of doing it.

--- End quote ---
I fail to see how fitting wider jets could ever compensate for altitude...

Bryanj:
Me 3, i thought higher was less oxygen so less fuel

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