captainwaldopepper wrote:
Hi Doc
I'm heading down to Minisport today to pickup some genuine Timkin wheel bearings as the ones I installed are cheap aftermarket types.
I had another look this morning and the wheels on my 850 (which has the same aftermarket bearings and is being restored so hasn't been driven yet) have the exact same problem.
I couldn't see any movement in the ball joints and after reading your thread, I now suspect the bearing spacers suppled with the aftermarket bearings units are too thick and this may be causing the wheel wobble problems.
Have you had any similar issues with Timkin roller bearings or is this just a problem with the cheaper aftermarket types?
Also, do the older ball bearing types have the same issues as I've heard these don't require a fine tolerance preload like the tapered bearings.
Any advice would be much appreciated.
Thanks
Dave
I find the aftermarket bearings OK if used with a spacer that gives correct .001-.002" preload. As I have previously stated this is often not the spacer they supply in the kit.
I always keep old spacers, in addition I have a few 1/2 machined (wider) ones that I finish machine to width if needed.
I've not had spacer problems with Timkens except on an old 997 Cooper swivel hub which was badly worn in the centre web.
If you fit Timkens and they are still loose, I'd say the hub's web is worn from the bearing cups spinning against it. So preload is lost.
The solution then is either renew the swivel hub, or follow my thread re measuring the endfloat, then machining the spacer width.
This has to be done accurately, the spacer has to be parallel when finished.
If the bearing cups are loose in the hub, renew the hub. But if they are still a neat fit but can just be spun by hand, I have had success with Loctite 609.
Ball bearings can have the same spacer width problem when fitted to old swivel hubs.
This is made worse on recent bearings with a 1/2 integral spacer on each. These cannot be machined, they need to be surface ground if found too wide.
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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.
