Templar X 250

[Okierider]

Here is the layout as it came out of my wheel, Demonstrated for just one side here as the other two bearings for the other side are elsewhere-



Outer spacer-seal-bearing-bearing-internal spacer-bearing-bearing-seal-outer spacer.

And yes it checks out as 25x42x9. Most of the trade references should properly be -2RS (2 rubber seals) or -2RS1 for big makers like SKF. They are also seemingly the same as a 6905-2RS. I think Timken has them listed as such but I know SKF does. Markings indicate C&U Bearings-“the largest bearing producer in China and one of the top 8 bearing manufacturers worldwide...” seemed to be fairly standard deep groove ball bearings, didn’t outwardly appear cheap and even after pounding one of the races with a flathead screwdriver to get it out it still spun fairly well, though the rubber seal was shot. Not the best, but far from the worst.
Of note-very little evidence of ANY lubricant used for install. Aside from the internal grease in the bearings everything else was VERY dry.



Bearings were SMASHED into the center spacer and then into each other. Absolutely zero movement until I got one to budge, then everything started spinning.

[superjocko]

Maybe the logic is that two Chinese made bearings equals one good bearing. Just kidding, of course (kind of).

[Okierider]

Originally Posted by superjocko

Maybe the logic is that two Chinese made bearings equals one good bearing. Just kidding, of course (kind of).

Ha!
I have 4 replacements coming from grainger-can’t beat their shipping. I’ll get some proper Japanese bearings like Toyo coming on the slow boat that is Amazon soon.

I’m going to check the length of that center spacer and see if it isn’t a smidge too long-theoretically as the bearings sit on a ledge milled for them it shouldn’t matter how much torque you put on the axel nut-if the center spacer is the correct length it won’t impinge the bearings. I have a hunch it’s a few thousandths too long.

[Thumper]

I think you are right. Tolerance must be pretty small on the fitment with such high forces on the axel pinching those inner races. I wonder if there's any precedence for dual double bearings? It is the first time I've seen it.

[superjocko]

Originally Posted by Okierider

Ha!
I have 4 replacements coming from grainger-can’t beat their shipping. I’ll get some proper Japanese bearings like Toyo coming on the slow boat that is Amazon soon.

I’m going to check the length of that center spacer and see if it isn’t a smidge too long-theoretically as the bearings sit on a ledge milled for them it shouldn’t matter how much torque you put on the axel nut-if the center spacer is the correct length it won’t impinge the bearings. I have a hunch it’s a few thousandths too long.

I believe a too long spacer would only prevent OD of the bearing from fully seating in the hub. Not good as the hub could fret laterally on the bearings. A too short spacer would cause deformation of the hub and bearing impingement when the axle nut is tightened. Right?

[Okierider]

Originally Posted by superjocko

I believe a too long spacer would only prevent OD of the bearing from fully seating in the hub. Not good as the hub could fret laterally on the bearings. A too short spacer would cause deformation of the hub and bearing impingement when the axle nut is tightened. Right?

Off the top of my head, I don’t think so.
The bearings aren’t held in place by the spacer-they sit in on a seat machines into the hub. The center spacer is the same 25mm diameter as the inner race, when it’s not pressed in between the two innermost bearings it freely moves around inside the hub. So on my bike when everything was tight the outer race was set firmly into the hub on its seat (definitely not moving) and the inner races were smashed between the inner and outer spacers causing impingement. If the center spacer is even a bit too long it would cause this to happen even at nominally low torque on the axel nut.
If the center spacer was too short it could allow for lateral movement of the inner race when the outer spacer pushed on them from the outside. Definitely not good.

At least I think so, I’ll have to take a closer look when I get home from work today.

[Thumper]

Originally Posted by superjocko

I believe a too long spacer would only prevent OD of the bearing from fully seating in the hub. Not good as the hub could fret laterally on the bearings. A too short spacer would cause deformation of the hub and bearing impingement when the axle nut is tightened. Right?

That makes sense if the outer race can move...

If the outer race wasn't tight, it could move to whatever position the inner sleeve puts it. But the bearing won't move if the outer race is tight, won't move. And there are two of them on each side in this case

I would like to switch to a crown bolt on the axel nut. The front axel is not held by the axel/axel bolt in the front forks. It is clamped in place, so you can put reasonable tension on that bolt. Other than making sure the nut doesn't loosen, I don't see any need for tightening that rear axel nut excessively.

The rear wheel should spin freely. That is probably the real test.

[Okierider]

I’ve thought of reinstalling this all but replacing the ny-loc axel nut with a castle nut and drilling the axel for a cotter pin-then you wouldn’t be reliant an pound-feet if friction to keep the axel in place, instead it would be a mechanical lock.

[Thumper]

Originally Posted by Okierider

I’ve thought of reinstalling this all but replacing the ny-loc axel nut with a castle nut and drilling the axel for a cotter pin-then you wouldn’t be reliant an pound-feet if friction to keep the axel in place, instead it would be a mechanical lock.

I never apply more than maybe 50 (NOT 200-typo) foot lbs and it just never budges. The maximum force the rear axel faces is pull, and the adjustment stand-offs prevent the axel from sliding forward.

Side note... I would bet that one good bearing on each side with correct outer spacers and inner sleeve/spacer would be 100% stable. I see no good reason for doubling the bearings unless they are trying to spread the load on the hub. Isn't the hub strong enough for taking that load on one bearing circumference on each side?

[J4Fun]

Hi Thumper, just wanted to bring to your attention, the 200 foot lbs. in your post 1674. Did you mean inch lbs. or maybe 20 foot lbs.

[Okierider]

Originally Posted by J4Fun

Hi Thumper, just wanted to bring to your attention, the 200 foot lbs. in your post 1674. Did you mean inch lbs. or maybe 20 foot lbs.

I want to see that torque wrench

[Thumper]

Typo. More like 50 foot pounds. I just checked it. Not 200!

I guess that's close to recommended (~65 foot pounds for a CRF250, for instance). I am just paranoid about damaging the bearings.

[Okierider]

Got my new bearings from grainger.
They aren’t great…at all, but they got here quick and seem to work better than I thought.
I fully expect to have to replace them soon, so I’ll have a stock of Toyos coming from Japan on the slow boat.
The hubs were EXTREMELY rough where the bearings sat. I had to smooth them out with some very fine sand paper just to make an even surface to pound the new ones into.
Fully seated the center spacer does impinge on the inner races, so when I do take them out I’ll be shortening that a bit.

[Mikd]

So the stock skidplate while thin probably saved me today. Large flat rock tilted up lifted the bike a bit while traveling slowly in 2nd gear. Skid is thrashed and did contact the case boss for the drain bolt. No leaking so far, fingers crossed.

[Weresquatch]

Glad everything is okay. Others have downplayed the bash guard on there but I think it's pretty reasonable especially when considering how beefy the frame is and the purpose of the bike.