850T bearings now sorted

I have removed the circlip from the brake side, the oils seals from both sides and the big circlip, cover and cush drive rubbers from the drive side and I am left with the two bearings in the hub with a tube in the middle. I cannot remember if these just press out (long time since I changed them last).
Looking at a section through the hub it appears that there is a shoulder in the hub so the don’t press out. Haynes is unhelpful as it says just lift the bearing and the workshop manual only deals with disc rear brake bikes. The bike has been standing for many years and the bearings do not just “lift out”
Any ideas?

Lots of antiseize for a week then gently drift them out.
Only done this with a disced bike and I used an aluminium ruler as the drift.

Thanks Ian, I am applying antiseize daily and have suitable drifts. The Haynes manual shows a smaller diameter to the hub in the middle that the bearings sit against, if this is the case I will not be able to drift from one side to the other unless one bearing is already out. I wonder if this diagram is correct? Haynes also says that the 750S and 850T do not have a cush drive, but mine does, and it is not an 850T3 hub because it has a drum brake. Maybe mine is a late 850T?

I have managed to get the bearings out at last, they sit in a shouldered stop in the hub so was unable to drive them out with a drift on the outer race but the centre is shouldered too, so I was able to drive one side out that way.

Haynes manual shows a diagram of 850T/750S which does not match my bike. I have an 850T/750S/V7 Sport workshop manual and that says nothing about removing the bearings, and the 850T3 manual I have is not relevant.

I changed the hub when the brake liner got cracked, I was told it was an 850T wheel, the components match the parts diagram exploded diagram except I have no shims in there and only one oil seal ring, I will try and source one (90 40 32 47) or get one machined to suit.

I am now looking forward to a trip to Essex Bearings in Maldon to get replacement bearings for both wheels, swinging arm and stearing head.

Onwards and upwards! :smiley:

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The last problem I have is removing the tapered bearing outer cases from the swing arm and from above the bottom yoke on the steering head, any ideas?

When I had my swing arm powder coated I left the outer race in and just taped over it. I have heard of people either cutting through them with a Dremel or running a ring of weld around them to get them out. I believe there is a special facory tool to drag them out.
Not sure if yours is different to the later frame, but I managed to drift the headstock bearings out working through the tube. There should be a small lip visible to tap away at. As usual, a bit of heat may help.

Thanks Don, the swinging arm outer races were taped over but I have almost decided to replace them, it just depends if they will come out easily or not. I don’t want to attempt removing them only to fail and damage them.
Steering head is not standard as I have 38mm Mazaccohi forks and yokes. I will inspect the race for damage and again may leave it there. If I could remove the central shaft from the bottom yoke I would be able to drift the race off?


I have read Guzziology and decided to leave the cups in the swinging arm as they appear in good condition. I think I would need a puller to remove them as Don suggested but as they are less critical then the steering head I will take the risk to leave them in place. The steering head lower cup I will cut with a Dremel to make removal easier.

Bearings now bought

I removed the bearing cup from the steering head by cutting it almost through with a Dremel and then splitting it with a cold chisel. Now for the swing arm cups. I need a slide hammer with hook ends to get behind bearing cups, I will contact a few bike shops and engineering works around here in the morning. Moving on again :smiley:

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I have just bought a blind/internal puller set with a slide hammer on eBay, I read a post on the other place after a google search and now think I have the solution to pulling the swinging arm bearing shells. Apparently, the right hand one needs a little dremel work on the puller, to allow it to fit between the back of the bearing and the right hand side of the drive shaft tube.
Exciting eh? :smiley:

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