rear wheel fit problem

i just put new sealed bearings in the rear wheel, but now i am struggling to get the the big spacer back infront of the speedo gearbox and tophat spacer, without the top hat spacer the big spacer goes in. but just the thickness of the tophat lip is enough to prevent a successful reassemble,

also the stepped spacer between the bearings seems to have been abused and swollen, had to cut the old bearing off.

the only thing i can think is that the outside bearing isn't fully seated, but since it goes in first that should not be a problem.

any suggestions about where i have gone haywire?

Are you sure you refitted the bearing spacer correctly with the short reduced diameter end on the drive side?

yes the long end was sticking through the bearing on the speedo drive side.

New cush drive buffers? Sometimes I need to use a lever to pry the swing arm enough to get that axle spacer in. Sounds like you’re close if only the top hat thickness is in the way.

I pry mine also.... No shame in it. Don't know what I'd do roadside though.

I use a piece of board on the timing side to lever the wheel over enough to get the spacer in. It felt wrong the first time I did it, but most things do.

i should have also added that its a new speedo drive unit , supposedly the vendor claims its not a knockoff, so i also tried a wornout old one, the spacer still would not fit.

i have not been into the drum at all yet.

one question - how far out are you from getting the spacer in position? FWIW, just did cush buffers. I found that if you install the axle shaft WITHOUT the spacer first, it helps installation. this supports the wheel assembly and allows you to rock the wheel assembly to work the tabs into the spacers. engage enough threads to hold the assembly. I rocked wheel assembly at the 3 and 9 o'clock position, rotated it about a quarter turn , rocked again, rotated and rocked, and so on. when the wheel assembly was in close proximity, I used the nylon pry-bar and slid the spacer in as far as it would go. removed the axle bolt, and used a plastic mallet to tap the spacer into position. re-installed the axle bolt. hope this helps. good luck....

the bushing is about 0.040" to long . i did lube the spline for the cush buffers, thanks will try your idea.

I have had this issue to a lesser or greater extent each time I have the rear wheel off on 2 different Commandos (71 & 72). I use a piece of all thread with nuts & washers to open the gap between the swing arm & top hat enough to slide the spacer in.

I reset the brgs, and was able with a bit of leverage to get it in thanks for the suggestions, its still tight, so i may reproduce a space with shorter length...

Since my post #10 above I have learned that the technique I described there has been responsible for distortion of my speedo drive housing. This problem and its solution are described on other threads.
When I put the rear wheel back on my 71 Roadster the other day, I discovered a much better technique (that maybe many folks out there already use). I realized that the reason the wheel wouldn't fit easily was because the cush drive pegs were not fully inserted (new buffers cause a really tight fit). So now I first install the axel without the speedo drive on it but add another washer or 2. I then tighten the axel into the dummy axel until I see the chush drives are in as far as they can go. (That leaves about a 1mm space between the hub & brake drum). I take the axel off again, put the speedo drive on, and the big spacer slides right in over the top hat perfectly. No force necessary.

I fitted a new speedo drive and top hat last week and had the same problem. The technique that worked for me was to locate the wheel onto the three Cush drive pegs, withe the speedo drive and top hat fitted. Then while keeping pressure on the hub to make sure the wheel doesn’t fall off the pegs, push the rearmost part of the wheel towards the chain side of the bike. This opens up the space at the back so that the spacer can just be inserted, then tap in with rubber hammer.
Works best if one of the Cush pegs is at the 9 o clock position, looking from the speedo side.

The 3 paddles on the drum that engage with the cush-drive bushings have a generous radius in the rotational axis – good design as a sharp corner would be a stress riser. However, that radius interferes with the relatively sharp corner that new bushing create. The last time I installed new bushings I used a utility knife and put a 1/16” x 45 chamfer on the interface edge. This reduced the drum to wheel gap by approximately .040. I added a bit of silicone grease on installation. It was still a very tight fit-up but I was able to assemble.