Author Topic: Simple Question (Old Timers Once Again!)  (Read 1170 times)

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Offline NewOldSchool

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Simple Question (Old Timers Once Again!)
« on: June 29, 2012, 10:10:55 AM »
So I am currently rebuilding my carbs and lo and behold the clip is already set at the 4th notch from the top, so they have obviously been tampered with in the past.

Looking at the needle it is stamped Keihin 2720.

Anyone know if this is the stock needle or is this an optional one with a different taper from stock?
« Last Edit: June 29, 2012, 10:28:15 AM by NewOldSchool »
Not putting miles on your bike is like not having sex with your Girl Friend so she'll be more desirable to her next Boy Friend.

Offline Bob Wessner

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Re: Simple Question (Old Timers Once Again!)
« Reply #1 on: June 29, 2012, 10:54:23 AM »
Knowing what bike and carb models would get you a more accurate answer.
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bollingball

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Re: Simple Question (Old Timers Once Again!)
« Reply #2 on: June 29, 2012, 10:59:39 AM »
Simple answer What bike ;D

Offline NewOldSchool

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Re: Simple Question CB750 K4 (Old Timers Once Again!)
« Reply #3 on: June 29, 2012, 11:48:09 AM »
HAHA made myself look like an idiot!  I had that info in the title, but changed it.

1974 CB750 K4 with Stock Keihin carburetors.
Not putting miles on your bike is like not having sex with your Girl Friend so she'll be more desirable to her next Boy Friend.

Offline lucky

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Re: Simple Question (Old Timers Once Again!)
« Reply #4 on: June 29, 2012, 04:18:35 PM »
Two models of carbs had the clip on the 4th notch down from the top standard.
One model of carbs had the needle on the 3rd or middle groove of the needle.

You will need to look on the carbs to find the number.
The 7A version had the needle clip in the middle position or 3rd groove down from the top.

Offline NewOldSchool

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Re: Simple Question (Old Timers Once Again!)
« Reply #5 on: June 29, 2012, 07:00:48 PM »
Two models of carbs had the clip on the 4th notch down from the top standard.
One model of carbs had the needle on the 3rd or middle groove of the needle.

You will need to look on the carbs to find the number.
The 7A version had the needle clip in the middle position or 3rd groove down from the top.


Always a wealth of knowledge Lucky!

They are the 657B carbs.

Stampings say 675B and then ALG on the carb body.

Im wondering if the needle in it is the stock Keihin needle or if it has been replaced by a previous owner with an aftermarket or optional one.

The current needle is  a Keihin 2720. (possibly 27201 but I can't tell if it is a stamping mark or not)
Not putting miles on your bike is like not having sex with your Girl Friend so she'll be more desirable to her next Boy Friend.

Offline cgswss

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Re: Simple Question (Old Timers Once Again!)
« Reply #6 on: June 30, 2012, 05:05:03 AM »
Just wondering, but was the bike running before you started on the carbs?  If so id it run good except for idling?  I'm from the "if it ain't broke..." school, if it was running good why change it?  If not, get the bike running first and see how it works.

Offline NewOldSchool

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Re: Simple Question (Old Timers Once Again!)
« Reply #7 on: June 30, 2012, 08:05:51 PM »
Just wondering, but was the bike running before you started on the carbs?  If so id it run good except for idling?  I'm from the "if it ain't broke..." school, if it was running good why change it?  If not, get the bike running first and see how it works.

The bike was running fine, but I am putting a 4 into 1 exhaust on it and they hadn't been balanced in 2 years, it was also beginning to idle rough and the floats were all at different levels.

All those added up to wanting to do a simple rebuild/refresh and new jets to compensate for the K&N and 4 into 1.
Not putting miles on your bike is like not having sex with your Girl Friend so she'll be more desirable to her next Boy Friend.