Re: [ST]rear hub play. follow up

[Frederic.Nizery@xxxxxxxxxx]

follow up. Long but important (I think)

first of all I didn't want to frighten any one about bearing seizure or 
something.
Remember fellow listers. My original question was: do you check on a 
regular basis the rear bearing play.
So , in other words, can all of you go in your garrage, grab the rear 
wheel at the top w/ one hand
and at the bottom w/ the other , push
on one hand and pull on the other alternatively. Then get back to you pc 
and tell if you detected a play.

If there is a play no need to suicide immediatly. Rather, read here below.

So here is the folow up:

I asked the question to my fellow mecanic at my dealer. What he said is:
- they replaced the rear needle bearing (recall) because the quality of 
the outer cage was bad and there was a
hight risk of deterioration. The provider of the replacement was 
apparently differrent. (which was it ?)
- he said also that triumph didn't provide any measurement figures to 
check any play.
- he said that he wants to see the bearing journal of the axle and the 
hub to be able to judge my case.
- he said that as far as there is no visible deterioration of the 
journal or the bearing and if there is a sufficient
amout of grease, it would be OK (no crick, no corrosion, no groove...).
- he said his experience tends to show on some bike a play when hot 
(after driving) disapearing when cold (let's say after a night).
- he teached me something about the play I should have known ( I 
forgot): The nominal play of a bearing is indicated in the reference.  
C1 is 0.1mm
C2 is 0.2mm and so on.  He said  that on racing bikes,  they put maximum 
play bearing to allow maximum speed. That was new for me.
Even the play figures were surprising. I would have think that  the 
range were in thousandth of milimeters. He said  .1 mm play  is 
undetectable.

Then we went to the show room and tested the play on a new ST: no play
Then we tested the play on a second hand ST and there was a play even 
bigger than mine.
I detected no play on my brother in law ST (24 000 km). Dealer maintened 
(the same by the way).

Next step for me ( you know which it is for you ;-) ) is to take  the 
hub appart (again but I am getting faster an faster in this job), get 
the axle
and the hub to him and measure together the wearness of the journal. 
They have a surface comparator. If it's very low,
I will change the bearing for security  and that will be it. The bearing 
is 45 euros.
It' is not even sure that I will have no play afterward. But I will let 
you know.

But anyway the maintenance schedule says to regrease the bearing every 
20k, not to change  the bearing. For those  of you that do their own
maintenance but didn't do that it's not so complicated. But I would 
advice to take the hub off the wheel to be able to clean up thoroughly
the old grease and the put new one. vertically in a small tank w/ 
solvant needle bearing down. use a brush and don't splash the solvant.
For that be carefull not to put solvant on the  double roller sealed 
bearing (opposit side). When greasing up take care of making
the grease going behind the deedles rolling then around.

And do not forget to put the spacer washer between the torque absorber 
and the double bearing (left side) when you put the assembly back in.

The dealer used molybden bisulfur grease (grey) but when I regreased it 
I found green grease which tend to proof it was either synthetic
or lithium grease. I put myself lithium grease.

Does anyone need to know the procedure to take the hub appart?

Keep you posted.


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