Author Topic: Case boss by counter sprocket  (Read 1937 times)

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Offline Johnny340

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Case boss by counter sprocket
« on: June 30, 2017, 04:26:54 PM »
Is this broken boss just where the counter sprocket cover bolted to? I'm not sure I can run the stock cover anyway with offset sprockets so was thinking about ditching it. I guess that's two questions..

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1975 CB750F0 Super Sport
1972 CB750K2
1981 CB650
1974 T-500
2003 GSXR750
2006 YZ250

Offline disco

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Re: Case boss by counter sprocket
« Reply #1 on: June 30, 2017, 05:12:52 PM »
Just for the sprocket cover.
1976 CB750 K6 Sapphire Blue
1972 CB750 K2 836 Orange Sunrise
1972 CB750 K2 Candy Red
1972 CB750 K2 Candy Gold'

Offline Johnny340

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Re: Case boss by counter sprocket
« Reply #2 on: June 30, 2017, 05:14:10 PM »
Just for the sprocket cover.
Ah, I see that from your pic. Any problems not running that cover?

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1975 CB750F0 Super Sport
1972 CB750K2
1981 CB650
1974 T-500
2003 GSXR750
2006 YZ250

Offline disco

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Re: Case boss by counter sprocket
« Reply #3 on: June 30, 2017, 05:23:01 PM »
The sprocket cover uses two bolts to secure it. The bolt hole at about 11 o'clock above the sprocket, is the 2nd fixing point. I think you could still run the cover OK with only one bolt.

Why not JB Weld it? Selley's 'Knead It' etc?
« Last Edit: June 30, 2017, 05:26:54 PM by disco »
1976 CB750 K6 Sapphire Blue
1972 CB750 K2 836 Orange Sunrise
1972 CB750 K2 Candy Red
1972 CB750 K2 Candy Gold'

Offline Johnny340

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Re: Case boss by counter sprocket
« Reply #4 on: June 30, 2017, 05:26:48 PM »
The sprocket cover uses two bolts to secure it. The bolt at about 11 o'clock above the sprocket, is the 2nd fixing point. I think you could still run the cover OK with only one bolt.
I see. I'm still thinking I don't want to run the cover because the chain will interfere running on offset sprockets..
Does someone make a plug so crud won't go down the hole into the shift mechanism?


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« Last Edit: June 30, 2017, 05:55:47 PM by Johnny340 »
1975 CB750F0 Super Sport
1972 CB750K2
1981 CB650
1974 T-500
2003 GSXR750
2006 YZ250

Offline 754

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Re: Case boss by counter sprocket
« Reply #5 on: June 30, 2017, 09:57:03 PM »
That usually has your wires in there.
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Kelowna B.C.       Canada

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73 836cc.. Green, had it for 3 decades!!
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Offline Johnny340

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Re: Case boss by counter sprocket
« Reply #6 on: June 30, 2017, 10:05:19 PM »
That usually has your wires in there.
Will that be enough to block off that hole? Am I crazy to run without the cover in place?

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1975 CB750F0 Super Sport
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2003 GSXR750
2006 YZ250

Offline PeWe

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Re: Case boss by counter sprocket
« Reply #7 on: June 30, 2017, 11:06:40 PM »
Cover protects against dirt and grease. I should repair it with a good chunk of JB weld, make a new threaded hole, probably with a thread insert glued, time-sert
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline 754

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Re: Case boss by counter sprocket
« Reply #8 on: July 01, 2017, 09:26:28 AM »
You can cut part of your sprocket cover off, including the lower bolt part... Super easy to put in, still keeps the Mungue off everything..
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Johnny340

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Re: Case boss by counter sprocket
« Reply #9 on: July 01, 2017, 09:31:31 AM »
You can cut part of your sprocket cover off, including the lower bolt part... Super easy to put in, still keeps the Mungue off everything..
I like that idea! Solves both problems. 👍

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1975 CB750F0 Super Sport
1972 CB750K2
1981 CB650
1974 T-500
2003 GSXR750
2006 YZ250

Offline 754

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Re: Case boss by counter sprocket
« Reply #10 on: July 01, 2017, 09:58:57 AM »
I think it was a mostly vertical cut.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Johnny340

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Re: Case boss by counter sprocket
« Reply #11 on: July 01, 2017, 12:47:22 PM »
I think it was a mostly vertical cut.
Yes, this should work. Thanks for the suggestions!
I don't need much of an excuse to take it the new plasma cutter..


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1975 CB750F0 Super Sport
1972 CB750K2
1981 CB650
1974 T-500
2003 GSXR750
2006 YZ250

Offline 754

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Re: Case boss by counter sprocket
« Reply #12 on: July 01, 2017, 01:08:50 PM »
If it gets too dirty, cut the next one from top right corner..straight down.

Looks good though..
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline disco

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Re: Case boss by counter sprocket
« Reply #13 on: July 01, 2017, 05:55:06 PM »
Nice job! I now know what I'm going to do with my old sprocket cover with a divot out of it ;)
« Last Edit: July 01, 2017, 06:00:22 PM by disco »
1976 CB750 K6 Sapphire Blue
1972 CB750 K2 836 Orange Sunrise
1972 CB750 K2 Candy Red
1972 CB750 K2 Candy Gold'