Clutch basket wobble
- Thread starter BERT
- Start date
- Status
- Joined
- Jun 25, 2004
- Messages
- 929
My answer to solving clutch basket wobble is to put the outer primary cover back on... 
cliffa
VIP MEMBER
- Joined
- May 26, 2013
- Messages
- 4,129
I Like it & actually BERT, why not try it first before stripping the whole lot?My answer to solving clutch basket wobble is to put the outer primary cover back on...
maylar
VIP MEMBER
- Joined
- May 13, 2007
- Messages
- 4,213
FWIW, I think that the preferred method of dealing with a bent shaft is to remove it and check runout while mounted between V-blocks. Apply straightening force with an arbor press if needed.
I had a bent mainshaft long ago after a catastrophic primary chain failure (exploded alternator bits caught between chain and sprocket). Back then, Old Britts sold used parts and Fred hooked me up with one from his used stash. He told me that the straightest one he had measured .003" run-out, and that was exceptional. I bought it and still use it.
This was long ago and memory fades, but I seem to recall that the bike suffered from clutch issues with the bent shaft. Slipping or dragging, I was constantly into the primary cleaning plates and trying to figure out what was going on. Found the wobble by happenstance.
I had a bent mainshaft long ago after a catastrophic primary chain failure (exploded alternator bits caught between chain and sprocket). Back then, Old Britts sold used parts and Fred hooked me up with one from his used stash. He told me that the straightest one he had measured .003" run-out, and that was exceptional. I bought it and still use it.
This was long ago and memory fades, but I seem to recall that the bike suffered from clutch issues with the bent shaft. Slipping or dragging, I was constantly into the primary cleaning plates and trying to figure out what was going on. Found the wobble by happenstance.
Batrider and LAB:
Not so. The outside bearing diameter tolerance is only dependent of bearing size. Standard bearing tolerance is m5 (0 / 13 um for this size).
Medium tight fit bearing to basket may hint at a J6 or H6 tolerance at basket bearing seat.
=Knut
BERT
VIP MEMBER
- Joined
- Nov 23, 2020
- Messages
- 666
Thanks Timewarp, out of curiosity when you do your torquing intervals on the rotor nut do you slacken the nut first?
BERT
VIP MEMBER
- Joined
- Nov 23, 2020
- Messages
- 666
Thanks for everyone's insight with this. I am going to leave it as is and keep an eye on it. The readings are logged and will be checked next time I am in there. I don't really feel that a little more than .2% runout means much with a spinning mass like this hanging so far outboard of the bearing. I suspect that there was a destructive occurance inside the primary case at one time which tweaked the mainshaft. There was no evidence of damage inside the gearbox on a recent inspection. So if there happens to be another event, the runout will either be worse or better and for now I will let sleeping dogs lie.
Cheers, Dave
Cheers, Dave
Last edited:
- Joined
- Dec 3, 2012
- Messages
- 3,727
I backed it off a little each time.
Not quite the same but I took a lesson from that with my 1986 Husqvarna 400WR that I bought in 1987 and still have.
The factory manual said to do just that with the large external flywheel charging rotor and its taper, retorque at three set time intervals with one being maybe within 10 minutes, the last maybe an hour.
This was back in the 1990's and elected to just torque it once and be done with it without that retorque silliness.
At the annual Dickies farm two hour hare scramble, around the one hour mark I had been noticing a slight performance oddity then climbing a long uphill the engine started to slowly seize then came to a stop. (even more of an oddity)
I remember that day with clarity as it had blown the seal head in its Ohlins shock and was being beaten to death on some parts of the course and remember thinking a jet ski might be a good trade.
Husqvarna's were quite rare back then so stood out, I had to face the indignity and cruel chants as we came back in to the pit area on the back of a trailer.
There was no seizure, the rotor had moved and sheared the key retarding the ignition until the engine has stopped. (Which seemed impossible)
A new key and following the manual as far as the three step torqueing of the rotor nut it never happened again so took it as a lesson with tapers.
I have seen pictures of Commando D/S crank ends with the sprocket key area looking sad perhaps due to the sprocket taper not being seated or the nut not being torqued to spec (with a new serrated washer)
The devil is in the detail and might avoid walking, pushing or trailer rides.
BERT
VIP MEMBER
- Joined
- Nov 23, 2020
- Messages
- 666
Words of wisdom for sure. Thanks.
- Joined
- Dec 3, 2012
- Messages
- 3,727
The heckling from the crowd helped immensely.
It pays to follow the manual sometimes was the lesson (maybe not the Norton clutch nut torque setting)
70 ft/lbs seemed to be the number of the day for the Commando, rotor nut, sprocket nut and (incorrectly it seems) the clutch shaft nut.
I would imagine when you get on the gas all sorts of deflection is happening in the primary anyway.
I put a standard clearance (over the correct C2) bearing in the clutch so will keep an eye on the small amount of drum wobble, there is a remote possibility that any eccentricity of the spline to bearing bore (machining) could give some radial, maybe axial run out if turning the inner hub only. (I think but not totally sure)
A lot of old motorcycles have some form of mechanical oddities but still run fine.
- Status
Similar threads
