On Fri, 11 Aug 2017 16:02:43 -0700, Joerg
wrote:

On 2017-08-11 15:55, AMuzi wrote:
On 8/11/2017 4:26 PM, Joerg wrote:
On 2017-08-11 14:00, AMuzi wrote:
On 8/11/2017 3:04 PM, Joerg wrote:
On 2017-08-11 12:39, AMuzi wrote:
On 8/11/2017 1:00 PM, Joerg wrote:
The BB on my MTB makes a ticking sound when warmed up,
sounds similar to a hot car engine after it is turned off.
It has also develoved an ever so slight play, just a few
mils. It is an Shimano ES25 Octalink.

How long do you guys let that go before replacing?

Can anyone recommend a better quality BB for this that
lasts
longer than 5k miles and doesn't cost an arm and a leg?


Ensure the arms are not loose on the spindle first.


They are on tight. The play is also a bit sideways. If I
keep riding will it just become gradually worse or can it
fail catastrophically in the middle of nowhere?

On my last Shimano 600 BB I rode until it had about 0.1"
play in the largest chain ring and shifting trim became iffy
(old friction shifter bike). But that was an ajustable BB
where I could milk out a second life by mounting the cranks
180 degrees rotated.

What I don't like on these newfangled BBs is the left side
plastic cup. For the road bike I got a UN-55, only aluminum
on the left but at least not plastic.


Since it's shot and since you dislike low quality bearings
and nylon
cups, Tom Kunich is right; get a better quality version
of it.


The BB-5500 Tom suggested doesn't come in the same spindle
length. Which better one could replace the ES25 and is
compatible? The ES300 looks like it also has a plastic cap
on the left.


What length? The 5500 goes to 118mm besides the regular 110mm and 113mm.


The ES25 comes in 113mm and 121mm. I haven't taken it apart yet, wanted
to do that when I know what to buy and then order immediately after
disassembly, to minimize downtime.

I've seen the ES25 advertised in 113, 118 and 126 widths.

The BB-5500 I could only find in 109.5mm and 118mm. There were also
warnings that the spindle only accommodates older 9-speed group set cranks:

https://www.excelsports.com/main.asp...or=1&minor= 6

Quote "The pipe-billet spindle has eight 9mm deep splines and only fits
older Shimano cranks - many of the 9 speed 105 (not all), Ultegra and
Dura-Ace variety". I have a Deore M522 crank set on the MTB.

I've found that there are differences in Shimano stuff that appear at
first glance to be the exact same part. I bought a 50 tooth chain
ring, after carefully checking the bolt ring diameter, for a Tiagra
crank set. The new "105" chain ring appeared in the shop to be the
same as the Tiagra (with 2 fewer teeth, of course ) but when I came to
install it I found that the outer curves of the "spokes" was not the
same and while it fitted, and worked, it looked a bit odd.

Since then I've made it a point to limit my Shimano parts buying to
buying the correct model parts :-)
--
Cheers,

John B.