Author Topic: 74 CB 750 POPPING OUTTA 1ST  (Read 590 times)

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Offline marty1969$

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74 CB 750 POPPING OUTTA 1ST
« on: December 08, 2015, 11:42:16 AM »
are there dimensions on the inner and outter clutch and center clutch the discs go in, would this cause it to jump in and out of 1st, put new clutch discs and plates and even tore motor apart and replaced 1st gear and bushing 45T, EVERYTHING ELSE LOOKED GOOD INCLUDING SHIFTING FORKS AND DOGS

Offline goldarrow

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Re: 74 CB 750 POPPING OUTTA 1ST
« Reply #1 on: December 08, 2015, 11:57:07 AM »
Worn Shift drum?
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Offline 333

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Re: 74 CB 750 POPPING OUTTA 1ST
« Reply #2 on: December 08, 2015, 08:18:11 PM »
I'd say bent shift forks.
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Offline Gaucho

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Re: 74 CB 750 POPPING OUTTA 1ST
« Reply #3 on: December 09, 2015, 10:28:37 AM »
Some reasons could be:
Worn shifter fork
Bent shifter fork
Worn clutch dogs
In any case, you won't be able to see any of this without engine teardown. :-(
Gaucho

Offline bear

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Re: 74 CB 750 POPPING OUTTA 1ST
« Reply #4 on: December 09, 2015, 03:30:04 PM »
Maybe we should check the easy stuff before you start pulling motors. ;)

If it where me I would start by checking to see if there is anything physically stopping the detent locating properly on the shift drum stopper.

If that checks out, try adding a little preload to the spring on the detent arm.

Cheers,
Brian

are there dimensions on the inner and outter clutch and center clutch the discs go in, would this cause it to jump in and out of 1st,

Short answer,  No.
« Last Edit: December 09, 2015, 03:36:10 PM by bear »
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