Clutch basket wobble

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kommando said:
No as it gets magnified by the time you get to the edge of the basket, your own figures show 12 thou at the shaft becomes 20 to 25 thou at the larger diameter (surprised it not more). I would be looking for 1 to 2 thou runout on the shaft. It needs taking out and it tested between centres to find the bend plus the sleeve gear bushes checked as well.
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I am not understanding how the shown setup indicator reading would multiply along a line from the center outwards, no matter what the radius is. I understand how the indicator reading would multiply along the face of the same line from the center outwards though. I will have to give it more thought. However, it sounds like .012" is way to much and I am heading for a rebuild. Thank you for you input.
 
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As a minimum I'd take the clutch off completely and DTI the shaft as close to where the clutch mounts as possible
I wouldn't clock the pushrod hole because you don't know if it's been bored perfectly accurately
Sadly it's looking like you will need to remove the shaft to straighten/replace as komando has advised
 
baz said:
As a minimum I'd take the clutch off completely and DTI the shaft as close to where the clutch mounts as possible
I wouldn't clock the pushrod hole because you don't know if it's been bored perfectly accurately
Sadly it's looking like you will need to remove the shaft to straighten/replace as komando has advised
Click to expand...
Yes, I clocked the clutch center O.D. as well as the pushrod hole and it's the same value (give or take a thou) along the same orientation.
 
BERT said:
Yes, I clocked the clutch center O.D. as well as the pushrod hole and it's the same value (give or take a thou) along the same orientation.
Click to expand...
Sounds like you need to pull the shaft and check it to be sure
 
Is it possible I have bent the mainshaft by torquing the rotor nut to the specified 70# while having the crankshaft locked with a clutch basket locking tool jammed against the rear iso nut. Also, I had the gearbox in neutral. If it is possible I did bend it, I wonder if the mainshaft could have been better supported by being in gear?
 
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baz said:
As a minimum I'd take the clutch off completely and DTI the shaft as close to where the clutch mounts as possible
I wouldn't clock the pushrod hole because you don't know if it's been bored perfectly accurately
Sadly it's looking like you will need to remove the shaft to straighten/replace as komando has advised
Click to expand...
The pushrod hole is not true center. You are right. It must have been pure coincidence being concentric with the clutch center OD.
At the outside of the splines there is 5 thou runout. At the inside of the splines next to the circlip there is 2 thou runout.
Is this runout acceptable?
Clutch basket wobble
Clutch basket wobble

baz said:
As a minimum I'd take the clutch off completely and DTI the shaft as close to where the clutch mounts as possible
I wouldn't clock the pushrod hole because you don't know if it's been bored perfectly accurately
Sadly it's looking like you will need to remove the shaft to straighten/replace as komando has advised
Click to expand...
 
The difference from 2 thou to 5 thou over that short distance points to end of the shaft being bent?
Maybe put some pressure on the shaft for testing whilst turning the shaft just incase oil in the bush is playing a part here
It's a hard one to call without seeing it
Hopefully others will chime in and answer if it's acceptable amount of run out
 
baz said:
The difference from 2 thou to 5 thou over that short distance points to end of the shaft being bent?
Maybe put some pressure on the shaft for testing whilst turning the shaft just incase oil in the bush is playing a part here
It's a hard one to call without seeing it
Hopefully others will chime in and answer if it's acceptable amount of run out
Click to expand...
True. 3 thou over about an inch probably means more inside the case between the bearings. That would obviously mean that out and between centers it would show more than 1 or 2 thou so probably best to remove it to do a good job. I will give it a day or two to hear feedback before proceeding. Thanks for the help guys.
 
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I replaced the mainshaft with 5 thou runout measured using V-blocks. The new one I had bought years ago on sale from DomiRacer was near perfect. Hobot always used to say that they twist so cannot be straightened.
I believe the clutch bearing is supposed to be a C2 fit. I replaced mine once with a C2 bearing and it was a very tight press fit.
 
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batrider said:
I replaced the mainshaft with 5 thou runout measured using V-blocks. The new one I had bought years ago on sale from DomiRacer was near perfect. Hobot always used to say that they twist so cannot be straightened.
I believe the clutch bearing is supposed to be a C2 fit. I replaced mine once with a C2 bearing and it was a very tight press fit.
Click to expand...
Why did you replace the mainshaft?
 
batrider said:
Not sure but I think the internal fit is influenced by the external fit.
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Yes, but it shouldn't make a C2 any more difficult to fit than a standard bearing as it reduces the running clearance.
 
Also worth checking...

www.accessnorton.com

Wobbly clutch. Can anyone venture an opinion on this one please?

When you have the clutch apart again have a DTI available and check the runout of the mainshaft at the clutch end, ie its side to side wobble not the endfloat. The mainshaft is long and has the large weight of the clutch on its unsupported end and can be bent by the forces, it was the failure...
www.accessnorton.com www.accessnorton.com
 
BERT said:
Were there symptoms with shifting or primary chain wear with the bent one?
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Increased vibration would be my guess. But with a rubber mounted lump even that might be hidden.

Its the other things it could cause that’d worry me, premature primary chain wear premature gearbox wear, cracked gearbox case, etc…

IF it is definitely bent, it’s not worth the risk IMHO. Buy new and bin it.
 
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No symptoms of it being bent. I went in there to replace the layshaft bearing.
 
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