CB500 front drive sprocket question

[petersy]

I’m currently stripping a 1972 CB500 and because the chain had no split link, I removed the swinging arm to remove the chain.

In doing this, I noticed that the front drive sprocket could be slid off the drive shaft without undoing any bolts or retaining screws.

Is this normal, or should there be something to hold the sprocket in place please?

[Trigger]

Should be held on with a sprocket plate and two bolts.
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[petersy]

Trigger

There is a plate that bolts on to the sprocket, but nothing to hold the sprocket in place.

It would appear that the plate is to stop the sprocket from moving in towards the gearbox, but there is nothing to stop the sprocket from moving outwards, apart from the motion of the chain.

Pete

[totty]

I don't know this specific model but on all the ones I've seen the plate stops it being removed.

[Trigger]

The sprocket is held on the shaft by the splines and it is held in place from the plate that rotates and then the bolts hold it in place.

[petersy]

I still don't see how the plate keeps the sprocket in place, if the plate only bolts onto the sprocket and nothing else.

When the plate is bolted to the sprocket, I can slide both items onto the drive shaft, but there is nothing to hold the sprocket in place (only the chain).

I will take another look at it tomorrow and see if I can figure it out.

[ST1100]

I still don't see how the plate keeps the sprocket in place, if the plate only bolts onto the sprocket and nothing else.

IIRC is there a groove/cut in the splines of the driveshaft; the plate's teeth "twist" into that and is then locked in position with the two bolts; thus eliminating lateral movement of the sprocket...

[hairygit]

If you look at the shaft closely you will see a groove cut around the circumference, the plate is placed on the splines, then rotated until the bolt holes line up with the holes on the sprocket, then bolted to the sprocket. The design of the plate let's it slide onto the splines, then when the bolt holes are lined up you will find it is locked in place, and the sprocket cannot move in or out on the shaft.

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[petersy]

I think the penny has dropped.

So the sprocket goes on first, followed by the plate, which when tightened down, is forced against the spline to hold it in place.

Thanks guys, Ill try it tomorrow.

Pete

[Chris400F]

Sort of, but not exactly forced against the spline.
The plate should have 'teeth' which fit in the splines on the shaft.
Fit the sprocket then slide the plate on and rotate it by half the distance between splines so the teeth are now in the groove in the shaft and stop lateral movement of the plate.
At this point the holes in the plate will hopefully line up with the holes in the sprocket so when bolted together the sprocket is also located laterally.
If things don't look to be lining up correctly you might try turning the plate over - I can't remember whether they are usually symmetrical.

[petersy]

Finally got the sprocket on and locked in place today.
 - thanks for the advice everyone.

Pete