[ST] RE: st-digest V2001 #646

["Keith Tynan" <keith@xxxxxxxxxxxxxxx>]

> Date: Tue, 23 Oct 2001 21:23:24 -0500
> From: "Alex Ozzard-Low" <alexol@xxxxxxxxxxxxx>
> ...
> How do you know when you chain is worn out?  It hasn't stretched very much
> in 12k miles (apart from initially) and has only needed adjustment about
> four times.  It gets oiled regularly with chain wax.  The central roller
> feels loose, but I can't "pick up" a link off the sprocket, which
> used to be a guide way back when.  The sprocket is only very very slightly
worn.

Hi Alex,

Nice to see you taking chain life seriously, now that the belt drive option
has fallen through. I'd just transferred the dosh when Juergen told me of
the failure of the prototype. ~:(

As far as I know, there's no 'one touch' option for checking chain wear, but
you might look into the following:

Prevention
- ----------
1) Good quality chain and sprockets. IMHO this equates to DID X-ring ONLY
with steel sprockets (heck, if you wanted to save weight, you wouldn't have
bought the ST!). I've consistently had problems with stretching Regina
chains, and wouldn't touch them with a barge pole.
2) Make sure it's well lubed. This means either a squirt of PJ1 (my
recommendation) every 250 miles or a drip feed from a Scottoiler (the latter
for the last 5 years).
3) Make sure the rear sprocket is concentrically mounted - check with feeler
gauges between the sprocket and the cush-drive before tightening up the
sprocket retaining nuts.
4) When any of [chain, front sprocket, rear sprocket] is up for replacement,
replace the lot (or repent at leisure).
5) Make sure it's properly adjusted - too tight and it'll shag the chain and
the gearbox bearings; too slack and (IMO) you'll get stiff gear changes and
a lot of noise.
6) Clean it at least once a year. DID recommend cleaning using paraffin
(kerosene-US?). BTW - forget about fancy chain cleaners - rubber gloves and
a toothbrush is cheap and effective (but the use of the toothbrush in your
cake-hole again is not recommended). It's a mucky job, but well worth it.

Given the above, and not too many wheelies/burnouts, you should get at least
25 kmiles out of a chain.

Diagnosis
- ---------
7) When you check the play (midway between centres), use a moderate pressure
up and down (not white knuckle). Check every 10 pins (5 links) for 3 loops
of the chain. Expect anything up to 10mm variance, as the chain WILL wear
unevenly. Anything beyond this is a sign that all is not well.
8) Try the pull-it-off-the-sprocket test. If there is any pull-off, or you
want the re-assurance, check more thoroughly by attaching a 20kg weight to
the lower run, and measuring the pin distance on the top run. This simple
statement hides a lot of work like: where do I get a 20kg weight from?; it's
big, how do I suspend it from the lower chain run?; yes, I DO have to take
the chain guard off; I can't access the quoted 20 pins, can I use less and
multiply up (yes)?

Advice (free)
- ------
Before doing any of the above:

0-A) Take a good long fast ride, and reconfirm what you like about the bike:
its engine, the torque spread, the handling...

0-B) Tell yourself how much better these are than anything in the BMW
range...


Hope this helps.

Regards,
- --
BRG
email: keith@xxxxxxxxxxxxxxx
'00 Sprint ST BRG 'Wolfram'


     *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *
      The ST/RS Mailing list is sponsored by Jack Lilley Ltd.
          http://www.TriumphNet.com/st/lilley for more info
   http://www.TriumphNet.com/st for ST, RS and Mailing List info

=-=-=-= Next Message =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=