Hi, Am replacing the steering bearings on a 1994 M600 I'm rebuilding, and I'm stuck with the direction in which the locking nut on the top bearing goes - is it smooth side up or smooth side down? I looked in both Haynes and a service manual I have and both don't specify which side points upwards, but it matters to me Additionally, I understood that this nut should be tightened "by feel" so that the steering isn't to hard, but isn't too vague. Is there a specific torque to it?
It's a few years since I've done head bearings on one of these and to be honest I can't remember but looking at it logically the nut has to bear against the bearing inner to adjust the 'tightness' so I'd fit flat side down. Someone will probably correct me if I'm wrong. The bearings are taper rollers and no torque given. The usual practice is to tighten them until the bearings start to bind them back them off until they are just free.
Have a close inspection of the nut cut-outs......the spannering burrs on each slot should tell you which way round.....on yours, they look like they are on the smooth side, which means smooth side up.
I would say the washer has to contact the inner race of the bearing, so if the recess is too big a diameter to ensure that happens then it has to go in with the recess upwards and the flat side downwards. Nasher.
Unless the headstock design on the Monster is different to the SS, the nut thingy doesn't make contact with the bearing at all.....there should be a big dished cover washer between the bearing and the nut.....it is supposed to keep the dirt out (it doesn't btw).....see the photo above. The nut thingy has a chamfered outer radius on the smooth side which again suggests smooth side up....you can see it on mine in the photo.....it is smooth side up. Another observation.....I don't like the look of the threads on the steering stem....some completely missing.
I was aware of the dust cover but not sure if it's internal diameter matched the steering stem or outer diameter of the inner race. And yes the threads on the stem look pretty worn out.
Ah, well spotted Arquebus, so it shouldn't really matter which way up it goes, but the cupped washer being quite thin metal I think I'd rather still have the flat side down so the thin metal wasn't in shear over the inner bearing race diameter. My M900 is missing the Cupped washer, no doubt another of the many bodges the bike was subjected to before I brought it. Nasher.
The chamfer is what tells me it should be smooth side up, otherwise there is no reason for the chamfer. Also, what a water trap it would be if the nut thingy was smooth side down....just right for 'lubricating' the bearings. Among my collection of photos**, I have one or two of my bike before I replaced the headstock bearings (They had obviously never been replaced before I got it because they were caged ball bearings, not taper rollers. Full of rust and crap). **Nut can be seen chamfer up / smooth side up.
I was also confused which way up the chamfered 'nut' should go, thanks for this. My bike is a 900SS (1994) and weirdly I have no sealing washers either at the top or bottom of the stem, and no regular washers either, I think the previous owner might have made a bollocks of it - although in the 'exploded diagram' I found online sealing washers aren't actually shown. Surely this is wrong
