Mounting the rear wheel on the Mk3

The mk3 comes with an "easy dismount" rear wheel assembly that is a cruel irony at best. With the LHS assembly (sprocket, speedo drive, dummy shaft and washers) in place, there is exactly 6.25" between the sprocket plate and the inside surface of the RHS swingarm paddle (see photos below).







This is exactly the distance measured between the LHS of the Drive Centre and the outside of the caliper plate (as this entire assembly must fit between the sprocket plate and the RHS swingarm paddle). However, when I mount the wheel, I simply cannot generate enough clearance to allow the caliper plate (with its .91" protrusion at the axle) to mount between the wheel spacer and the swingarm paddle, In fact, I seem to lack more than 1/8" clearance, and that is with the aid of a 70 cm breaker bar spreading the paddle. What gives? Isn't this supposed to be a simple maneuver?

L.A.B., if you're out there, I'm in bad need of encouragement and technique. This problem has been going on for days.

rick in seattle said:

With the LHS assembly (sprocket, speedo drive, dummy shaft and washers) in place, there is exactly 6.25" between the sprocket plate and the inside surface of the RHS swingarm paddle (see photos below).

Click to expand...

Ok, somehow you don't have seem to have sufficient clearance between sprocket plate and the swingarm paddle? As that measures up as 6-5/8" on my MkIII.

rick in seattle said:

In fact, I seem to lack more than 1/8" clearance, and that is with the aid of a 70 cm breaker bar spreading the paddle. What gives? Isn't this supposed to be a simple maneuver?

Click to expand...

When it's right, it should all fit together quite easily.

If you remove the dummy axle nut, what amount of dummy axle protrudes from the swingarm?

Are you sure you have lined up the flats on the dummy axle with the slot in the swingarm? Otherwise the dummy axle won't be fully in position.

This is one of those questions that I've never asked myself as I've never had a problem with various hubs and cush drives.

The disc side looks OK so as L.A.B. says, the problem has to lie with the sprocket fixing. Any chance of a photo from the drive side to see how far the stub axle is protruding ?

Photo shows how much dummy axle should protrude with the spacer in position (speedo drive gearbox and washer to be added).

Note the flats on the axle that locate within the L/H S/A slot.

The dummy shaft protrudes 0.52" proud of the sprocket plate. The corresponding recess in the drive centre is 0.45" deep before arriving at the bearing sleeve. The flats on the dummy shaft are engaged into the slots on the LHS paddle - I now get 6-3/8" clearance - still no cigar.

When the nut is fully engaged in the LHS, the dummy shaft tip protrudes 0.93" from the outside surface of the paddle, i.e. it extends 1/4" or so past the end of the nut.

Just dashed to the garage and it's a bit difficult to measure in-situ but I've got 1" of exposed stub axle from the swinging arm to the tip of the threaded section.

This makes me wonder if you've got too thick a spacer in there somewhere by the speedo drive ?

rick in seattle said:

When the nut is fully engaged in the LHS, the dummy shaft tip protrudes 0.93" from the outside surface of the paddle, i.e. it extends 1/4" or so past the end of the nut.

Click to expand...

That sounds OK, however there's something not quite right with regard to the Blue grease seal, and maybe the bearing position as a result?

Compare the (Black) seal position of mine with yours. As yours seems to be too far inside the sprocket, or is that a sealed bearing with no additional seal?



Are you sure you have the correct width sprocket bearing?

If it's not that, then maybe the ends of the swingarm have been crushed together? I measure 8-1/8" between the inner faces.

I've got a washer between the bearing and the spacer on the dummy shaft to give me a bit more clearance on the speedo box. Removing this washer will move everything to the LHS by the 0.07" that separates our measurements. That's another 1/16" to add to the clearance.

Roger the bearing. Its a sealed double-row bearing from Walridge 06-7688. I mic'ed it befor putting it in; its a few thou THINNER than the stock bearing. No lube seal is installed.

I just removed everything; the clearance between the S/A arm paddles is 8.0" at the slots.

LAB and 79x100

Ok, hows this for a summary?

Currently I measure 6-3/8" clearance between the sprocket and the RHS Paddle, so, to get to your measurement of 6-5/8, I need to find the missing 1/4". My S/A has just been powder-coated, which could likely explain the 1/8" difference in the raw paddle clearance between my 8" and your 8-1/8". Removing the washer at the speedo box will gain me a bit more than 1/16". I'm inclined to force the arms apart to get the remaining 3/16", rather than grind off that expensive paint, although I could do just in the vacinity of the axle on the inner surfaces only.

Thanks to both of you for sticking with me in solving this problem. I't will be a matter of a 1/16 here and a 1/16 there. The important part to me is knowing the clearance and being assured that the assembly, with proper clearance, is smooth and without too much brute force.

Thanks again to both of you.