Author Topic: Swing Arm  (Read 1250 times)

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Offline Dion

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Swing Arm
« on: October 27, 2014, 02:11:37 AM »
Hi Guys,  Need help here. I’m busy dry assembling my Cr replica before I paint, however I have an issue with the rear wheel and the spacers. According to the workshop manual I am using the correct spacers, however I have a gap between the spacers and the swing arm. Does anyone know the correct measurement between the swing arm legs? The picture that I attached has been joined in the middle so that one can accurately see what the issue is.  Thanks guys.

Offline Sam Green Racing

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Re: Swing Arm
« Reply #1 on: October 27, 2014, 05:08:10 AM »
Dion, are you mixing parts, have you got an F arm and early K wheel ?

Sam. ;)
C95 sprint bike.
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Offline Dion

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Re: Swing Arm
« Reply #2 on: October 27, 2014, 06:31:28 AM »
Hi Sam, hope u feeling well bud. Yip I think i am. I bought 4 sohc bikes and stripped all to get the best parts. But i don't know what the actual sohc swing arm measurements  (Width) are? Can u help at all?

Offline JohnN

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Re: Swing Arm
« Reply #3 on: October 27, 2014, 06:47:46 AM »
My K2 & K6 swingarms measure 9-1/2" (240 mm).
John
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Offline Dion

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Re: Swing Arm
« Reply #4 on: October 27, 2014, 06:57:49 AM »
Thanks John. I'm going to measure as soon as i get home from work in the next hour. Forgot the measurement at home. This having to work is playing havoc with my hobbies :)

Offline 754

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Re: Swing Arm
« Reply #5 on: October 27, 2014, 07:40:44 AM »
Late K andF arm does not have a bolt thru the removeable end piece.
Maker of the WELDLESS 750 Frame Kit
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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 Dion

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Re: Swing Arm
« Reply #6 on: October 27, 2014, 09:24:12 AM »
Hi Guys, the pic that i previously posed on this thread, the Swing arm in the pic is about 265mm +/- 2mm wide.
I went and found all the swing arms that were in the bikes that i stripped and I am attaching a pic of those units to this post.
The Oval unit measuring 240 mm is the one that was in the bike that i am currently building when i bought it. I don't want to use it because all the pics i c of the CR has the rectangular swing arm in them.
Your thoughts are greatly appreciated. Thanks. How do i rectify this????

Offline Dion

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Re: Swing Arm
« Reply #7 on: October 27, 2014, 09:45:48 AM »
My build so far.

Offline Sam Green Racing

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Re: Swing Arm
« Reply #8 on: October 27, 2014, 10:42:46 AM »
Looking nice Dion. The biggest problem with mixing parts is not getting them to fit but getting them to line up.
I'm taking a guess here as I'm not 100% sure but on the A F and later K models, the gearbox sprocket was about 5 8ths of an inch further out from the cases than the early Ks. The swing arms were cranked out further to the left to clear the chain and the top suspension mount was longer on the left had side to line up with the one on the cranked out swinger.
The rear axle was longer and they had a sprocket carrier that was wider to allow the chain to line up.
You need to check all your part to make sure you have the correct ones.
Your swinger looks like it's from one of the ones I mentioned above. Drop a plumb line down from the top left suspension mount to see if it lines up.

Sam. ;) 
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline Retro Rocket

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Re: Swing Arm
« Reply #9 on: October 27, 2014, 03:49:45 PM »
Looking nice Dion. The biggest problem with mixing parts is not getting them to fit but getting them to line up.
I'm taking a guess here as I'm not 100% sure but on the A F and later K models, the gearbox sprocket was 10mm further out from the cases than the early Ks. The swing arms were cranked out further to the left to clear the chain and the top suspension mount was longer on the left had side to line up with the one on the cranked out swinger.
The rear axle was longer and they had a sprocket carrier that was wider to allow the chain to line up.
You need to check all your part to make sure you have the correct ones.
Your swinger looks like it's from one of the ones I mentioned above. Drop a plumb line down from the top left suspension mount to see if it lines up.

Sam. ;)

Fixed that for you Sam... ;)
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Offline 754

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Re: Swing Arm
« Reply #10 on: October 27, 2014, 03:53:32 PM »
Looks like a 77/78 arm to me.  Wider.. Longer..
 The early swingarm had the drilled hole and the axle plate was forged with raised adjustment marks.
 The latest one has steel plate (cheaper) axle mount with stamped in adjustment marks.
 If it is a late arm off a K, the brake arm attach bracket is similar to the early ones.. The F one has the attachment on the top side..
« Last Edit: October 28, 2014, 07:46:47 AM by 754 »
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 Dion

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Re: Swing Arm
« Reply #11 on: October 28, 2014, 02:14:09 AM »
Thanks for the help guys. Going to do some more measurements and post an update this evening

Offline Blackfin5

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Re: Swing Arm
« Reply #12 on: November 01, 2014, 09:35:31 AM »
Had exact same issue....I had mixed hub/spacer parts from different models.