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Author Topic: 76 750F carb differences  (Read 727 times)

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Offline xntrik

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76 750F carb differences
« on: October 25, 2014, 01:56:18 AM »
Hello all,

I recently purchased a set of carbs that were supposed to be K model roundtops 72-76 models. HOWEVER, upon later closer inspection while tearing down for cleaning, I noticed screens/filters on the float valve seat. This made me look at the casting numbers which were 064A-ANA which what I'm finding now are 75-76 model F carbs.

My biggest question is what are the difference between these? Are parts interchangeable with K's? Are the castings the same? Differences in venturi's? Any insight would be super.

Thanks all....



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Offline goldarrow

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Re: 76 750F carb differences
« Reply #1 on: October 25, 2014, 05:25:38 AM »
Smaller main jets.  That's all I know
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Offline xntrik

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Re: 76 750F carb differences
« Reply #2 on: October 25, 2014, 02:16:47 PM »
I'm missing two slow jets, no big deal, i compared and they're the same between K's. I'm also missing one float valve (seat is there) and wondering if they're swappable as well. I basically bought two sets of k's for a swap into my 750A, and one as a backup to a bobber build on a K4 I'll be undertaking. I'm tempted now to put the F's on the auto, and keep the K's as my spare....


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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: 76 750F carb differences
« Reply #3 on: October 25, 2014, 02:23:01 PM »
The difference is the needle/needle jet set.

Just cross reference parts to compare the parts numbers. May not tell you WHAT the differences are but it will tell you they are or are not different. I use Motogrid.com
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Offline xntrik

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Re: 76 750F carb differences
« Reply #4 on: October 25, 2014, 05:53:36 PM »
Needle sets, emulsion tubes, float valve SETS, are different according to parts diagrams. I'll have to physically compare the float valve itself (it's pretty obvious he F's have a screen on the float valve seat, and are different). I'll also try physical measurements of the body's as well.


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Offline ekpent

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Re: 76 750F carb differences
« Reply #5 on: October 25, 2014, 07:20:22 PM »
Aren't the 750 Automatic carbs smaller than K or F carbs ?
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Offline xntrik

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Re: 76 750F carb differences
« Reply #6 on: October 26, 2014, 12:47:24 PM »
Yes, but round tops are a bolt on upgrade if you use the airbox and insulators for them.


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Offline xntrik

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Re: 76 750F carb differences
« Reply #7 on: October 26, 2014, 02:00:56 PM »
Float needles are identical, valve seat bore/depth are identical. The depth of float seat on the carb body is identical. Carb inlet/outlet mouths are identical. I will check slides when I fully disassemble a K set. The idle screws on F's have a textured and elongated head to allow adjustment by hand rather than flathead (though it does have the flathead as well). The dimensions of F idle screws are identical to K's. The holes in the idle screws on the F appear slightly larger.


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Offline xntrik

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Re: 76 750F carb differences
« Reply #8 on: October 26, 2014, 06:16:34 PM »
F slides are 25.90mm wide 41.04mm long, stamped "2.5" and "102" underneath. Needles are stamped "271307".


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