Seven Fifty cafe-racer. Wheels: spokes and rims. Part 2.

As I wrote in previous part of the story, I got an issue with rear rim. The rim has 32 holes as required, but it turned out that dimples have holes frilled under the angles that were for around 10o steeper than holes in original rim. This meant that spokes were bent quite badly when nipples were tightened, just like this spoke on photo:

I tried to find solution through experiments with spokes but I found no spokes configuration that fit both, Honda Transalp rear hub and Warp 9 rim. To buy another rim wasn’t solution too, cause it automatically gave project delay penalty, not mention financial one.  Under such circumstances I was forced to find solution and I worked it out in the form of inclined (beveled) washers. It wasn’t easy, but I managed to make 38 washers (I needed 32, but I made spare ones in case of loss or dimensions mismatching).

They were zinc anodized and after that began to remind a Hatch laid by the Ring of Power:

Let’s take a close look on one of those little buggers of mine. From one side it has a skew to change the angle of a nipple and a chamfer for its better fitting.

Another side is rounded to fit better to dimple. You may also note that washer has a side hole. I designed it for manufacture simplifying and for washer positioning during assembling.

Buy the way, idea of my washers is not new. Honda use washers for spokes too, but they are not beveled, of course.

And here how it works.

As you may see, there are no bent spokes on initially assembled wheel.

This rim turned out to be even better than front one, so I managed to get 0.3mm of  lateral (out-of-round) and 0.2mm of axial (side-to side) runout.  The mount for indicators was, as usually, quite simple but effective.

In action:

As I tightened spokes, wheel became ready for installation of new seal and new brake disc:

Ready rear wheel:

And pair of wheels:

The shelves with new parts for Honda CB750 Seven Fifty cafe-racer became emptier without boxes with new Heidenau inner tubes.

I loaded my new wheels, new tires and new tubes into my car and drove them into the nearest tire workshop equipped with tools and balancing machines for motorcycle wheels.  Only when I returned to my garage with ready wheels I understood how tense I was that day. It took a half an hour of sitting in chair with my legs stretched on folding stool and a cap of strong coffee (strange thing but coffee make me rather concentrated and calm, than exited) to bring me back to norm.

Sure, I couldn’t resist shooting some photos:

I also installed  wheels on their places, even briefly:

Not a lot remained to be done before assembling cafe-racer and I hope I’ll do all preparation works fast, though sometimes small works take more time than big ones…


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