Author Topic: 73 CB750 Fork stud question, what size?  (Read 1937 times)

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Offline motomotard

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73 CB750 Fork stud question, what size?
« on: November 04, 2007, 07:36:42 PM »
So one of the bolts on the bottom of my forks is screwed.  The threads are gone on the nut and the bolt itself has started to strip a little.

Does anyone know what size nut goes on these exactly? Ive tried 8x1, 1.25, and 1.5, none of them will go on. I guess i just need to force one on but i want to know which size to try and do it with before i screw the bolt up even more.

pic of the bolts im talking about

« Last Edit: November 04, 2007, 09:29:29 PM by motomotard »

Offline Bob Wessner

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Re: 73 CB750 Fork bolt question, what size?
« Reply #1 on: November 04, 2007, 07:41:44 PM »
Unless they changed at some point, for the K0-K2, according to my parts list;

The studs are 8x49
The nuts/bolts are 8mm
We'll all be someone else's PO some day.

Offline 754

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Re: 73 CB750 Fork bolt question, what size?
« Reply #2 on: November 04, 2007, 08:19:10 PM »
Dont force them on, try cleaning them with a thread file or small 3 corner, sounds like they are burred or peened.. what happened to the ones you had before you coatedthe forks??

 They are studs, not bolts..
Maker of the WELDLESS 750 Frame Kit
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Kelowna B.C.       Canada

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

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

Offline motomotard

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Re: 73 CB750 Fork bolt question, what size?
« Reply #3 on: November 04, 2007, 09:29:14 PM »
what size 8mm, 1, 1.25, or 1.5?

the "studs" are clean, i still have the nuts, but one of them is totally stripped, no threads left

Offline 754

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Re: 73 CB750 Fork stud question, what size?
« Reply #4 on: November 04, 2007, 09:33:23 PM »
Are you buying local??.. just take a leg along and check against a bolt or Pitch Guage in the store..
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 crazypj

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Re: 73 CB750 Fork stud question, what size?
« Reply #5 on: November 04, 2007, 11:07:57 PM »
They are 8x1.25x 49.
Unless its stated different the standard thread sizes on Japanese motorcycles after 1967 (maybe 69?)
 From memory
 5x0.8 (except carb jets, can be 5x0.7, 5x0.75)
6x1.00
7x1.00
8x1.25
10x1.00, 10x1.25, 10x1.5 (some generator bolts and brake fittings)
12x1.25, 12x1.5
14x1.25, 14x1.5
16, 18, 20mm axle threads are standard metric fine thread (as opposed to metric coarse or DIN/SAE)
 Up to late seventies/early eighties Honda's used 1/8" Whitworth rolled thread on spokes. (55 degree thread angle)
PJ
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Offline motomotard

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Re: 73 CB750 Fork stud question, what size?
« Reply #6 on: November 05, 2007, 12:39:38 AM »
They are 8x1.25x 49.
Unless its stated different the standard thread sizes on Japanese motorcycles after 1967 (maybe 69?)
 From memory
 5x0.8 (except carb jets, can be 5x0.7, 5x0.75)
6x1.00
7x1.00
8x1.25
10x1.00, 10x1.25, 10x1.5 (some generator bolts and brake fittings)
12x1.25, 12x1.5
14x1.25, 14x1.5
16, 18, 20mm axle threads are standard metric fine thread (as opposed to metric coarse or DIN/SAE)
 Up to late seventies/early eighties Honda's used 1/8" Whitworth rolled thread on spokes. (55 degree thread angle)
PJ


awesome, exactly what i needed to know, thanks