Interesting thread, If I remember correctly one side of my back wheel has a double bearing and the otherside has a single row bearing. That single row bearing is the same as the front wheel bearing.
Correct except for the '97s.
Now both bearings are a press fit in the wheel and both go into the wheel until the bearing bottoms out in the bore.
Again, correct.
Now if you are planning on running an axle through the wheel and putting a nut on the end of that axle then winding that nut up tight, then you need a spacer between the bearings. That spacer needs to be as long as the distance between the bottom of the bearing bores in the wheel.
That's why it is left alone.
First question, why would you shorten it? Would that shortened spacer cause the inner races to apply side thrust to the bearings? If so then you will have very early failure of the bearings.
We don't shorten it. You've made an assumption.
Most ball bearings have little capacity to handle side thrust. The ones that the Valkyrie uses are somewhat able to handle side thrust.
Both the left and right rear wheel bearings on my '97 Tourer were made by NSK. I replaced them with 3204s made by SFK, another top tier manufacturer. Honda doesn't have bearings made specifically for them. They use commercially available bearings that meet their specs.
Double row bearings have a design problem and need to have tollarances very close or one or the other rows of balls will carry the load. Which means that you might as well have a single row bearing.
Really? That's very interesting considering double row bearings are specifically designed to carry higher rotational and angular loads and some motorcycle perfomance customizers are doing this modification to other makes, with engines that make ours look tiny and weak, for the added reliability the double row bearing gives. In addition, the rear wheel bearing that fails the most in the Valkyries is the single row 6204 left rear wheel bearing. As the left bearing is only supported by the axle and is subjected to braking forces as well, installing a larger, stronger bearing provides the left side of the wheel with a bearing better suited to handle those stresses.
If you were to replace the single row bearing with a double row bearing then you would have to adjust the spacer on that side to compensate for the thicker bearing. If you miss by as much as .001 of an inch or the ends of the spacer are not square then you will side load one or the other bearings and that bearing will have a short life.
Exactly. The 5204/3204 double row bearing is 6.6mm thicker than the 6204. That's why you have .260" machined off the small end of the spacer. Spending the few dollars to have the spacer machined will ensure the spacer is square. In addition, the spacer, as designed, allows for the easy removal and installation plus not every frame has exactly the same dimensions. The variance in the frames nullifies your contention the spacer has to be exact.
I gave this some thought and bought grade V bearings for the back and the front and have not had a problem since.
That's why I recommend buying bearings only from top tier manufacturers.
I should have made a spacer to make up for the difference between the single row bearing and the double row bearing and I would have a spare to use if the double row bearing fails. That side of the rear wheel would get a single row and a spacer to replace the double row bearing.
Let me make sure I understand this. You think replacing the right double row bearing with a single row bearing plus a spacer and sliding it into the final drive unit is a good idea? That's scary.
With 5204/3204 bearings on both sides of the rear wheel, I carry one spare bearing for the rear wheel and one 6204 bearing for the front wheel while on a trip. By using bearings made by top tier manufacturers, the chance of them failing is far less than bearings made by lesser manufacturers.
Marty