Author Topic: Will a CB750 K8 trans fit in an early K motor?  (Read 846 times)

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Offline mycb750k6

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Will a CB750 K8 trans fit in an early K motor?
« on: January 21, 2012, 08:31:04 AM »
I know some gears (2,4) are different and some have less cogs on the gears in the later models but what if I swapped everything including the shafts, bearings and clutch? Could I swap the entire trans into the early K case?

Offline the technological J

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Re: Will a CB750 K8 trans fit in an early K motor?
« Reply #1 on: January 21, 2012, 09:03:58 AM »
why not just switch bottom ends?keep the jugs, pistons and heads from the other bike
70 KO...sold to fund the ST http://forums.sohc4.net/index.php?topic=88800.0(Alpha)
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Offline 754

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Re: Will a CB750 K8 trans fit in an early K motor?
« Reply #2 on: January 21, 2012, 09:12:14 AM »
 What year K case. out put bearing got wider around 73. if you want to use the loder style sprocket carrier, you should change the sprocket shaft to the shorter (early)one..
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Offline mycb750k6

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Re: Will a CB750 K8 trans fit in an early K motor?
« Reply #3 on: January 21, 2012, 10:11:41 AM »
Hmmmm. well the K8 has VIN 3000..... and the K1 1111...  And I considered the K8 bottom end but (1) it's black and (2) I don't know that it's any good either till I open it up. This project has gone south in a hurry.

Offline CycleRanger

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Re: Will a CB750 K8 trans fit in an early K motor?
« Reply #4 on: January 21, 2012, 11:02:58 AM »
K8 output shaft is longer.
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Offline mycb750k6

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Re: Will a CB750 K8 trans fit in an early K motor?
« Reply #5 on: January 21, 2012, 12:13:29 PM »
Well that's it then. Thanks. How about the shift drum and forks. Are they exchangeable?