Author Topic: Correct gear shift fork wear limit? what are the 2 measurements in manual?  (Read 2200 times)

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Offline skishyishy

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Greetings again infinite source of honda knowledge!

I am currently inside the gearbox of my 74  750 and was checking the gear shift forks and drum for wear when I came across some confusing verbage in my manual.  Can someone please help me decipher the correct wear limit for my shift forks...

The manual states:

"Check the fingers on the shift fork using a micrometer and if worn beyond .240 in, or if the shift fork dog is worn to less than 0.260 in diameter, the shift fork should be replaced."

What is the difference between these two measurements?  The photo shows only the micrometer across the width of the fork tip (parallel to the shaft the fork runs on) and nothing else.  I had always thought this to be the 'dog', but calling out a diameter confuses me.  If this is the dog, what is the 'finger' measurement.  It seems important since my measurement on all three is approx .255 in. 

Can someone clarify the difference between the two measurements?

Should I just replace these forks and maybe the drum anyways since I am into the crankcase?  I suspect these are expensive and/or hard to find?

big thanks as always...

martino1972

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i think the dog is the pin that sits in the tracks of the shift drum,the fingers is the other end of the forks

Offline mystic_1

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Correct.  You want to measure the thickness of the pads at the end of the fingers (which ride in grooves in the transmission gears) and also the diameter of the pin (dog) which rides in the grooves of the shift drum.

mystic_1
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Offline skishyishy

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Makes perfect sense.  Thanks guys.

Offline 754

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You may be able to build up with plating..

 The tolerances are a guideline.. if it is shifting perfectly, I probably would just run them..
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