On 6/9/2019 7:41 AM, Theodore Heise wrote:
On Mon, 3 Jun 2019 12:26:26 -0700 (PDT),
jbeattie wrote:
On Monday, June 3, 2019 at 9:22:42 AM UTC-7, Sir Ridesalot wrote:
Let's share stories of when Gremlins strike.

My latest is my Schwalbe 30mm CX Pro cyclocross tire. It has
gone completely flat a couple of times lately. So, yesterday I
took the tube out and pumped it up quite a bit to check it for
pinholes. PAssed it numerous times under water in a large pan.
No bubbles at all. Even checked the valve still no bubbles.
Pumped up the tube more and left it to hang overnight. This
morning it was still full of air. Let the air out and placed
tube back under tire and mounted tire to the rim. Pumped it up
to 80psi and went for a ride. Rode for a couple of hours and
came home. Tire pressure still at 80psi. I can only conclude
that there are Gremlins in my apartment and they let the air
out of the tire. Note that the tire was completely flat not
just soft.

What have Gremlins done to your bike?

Not a gremlin, but a WTF? My son was having shifting problems
suggestive of worn cassettes, so I put on a new 10sp cassette
that I had hanging around for the bike (a CAAD 9 that used to
be mine). Shifted beautifully. We went for a ride, and the
cassette was rattling like it was loose. It was -- and it
needed a 1mm shim for the old 8/9 freehub body. It seemed fine
when I put it together. So, I put in the shim, and it silenced
the rattle. Oddly, there was no shim when I pulled the old
cassettes, and I don't recall ever using one in the past -- at
least not on a Shimano hub. Maybe I'm just getting addled.

This is too weird. We run a 10-speed Shimano cassette with a long
throw Ultegra road derailer on our tandem. Two weeks ago the
derailer body snapped, and I replaced it with a new part (same
model). The shop also trued the wheel and adjusted the derailer
hanger at the same time, though the hanger had been unaffected by
the derailer breaking.

Last weekend, we broke a rear spoke. I replaced the spoke, and
touched up the true of the wheel. Yesterday we were out riding,
and I realized I'd gotten the cable adjusted off by a gear. I
tightened the cable enough to cover the full range of 10 cogs, and
we then had some weird shifting problems. I gradually got the
cable tension dialed in, but there was a spot or two going across
the casette where the shifting just jumped, oor even auto shifted
at times.

After we got home, I took the wheel off to clean the cassette, and
discovered the cogs were loose. I out on a brand new cassettte,
and had the same looseness. How did this happen? The cassette
and rear der had behaved beautifully for many many hundreds of
miles.

I got a spacer at the LBS, and the looseness is gone. Haven't
ridden it yet, but it shifts fine in the stand, and I expect the
same on the road.



Yes, Shimano Ten format cassettes (whether Shimano brand or
not) use a 1mm spacer behind low gear. Sprockets loose on
body is an amazingly common and annoying service error both
at home and in some shops.

Intermittent or inconsistent shifting, if yet unresolved,
may well be a kinked gear wire, a fraying gear wire ( look
in/near shifter!) or damaged casing (usually at first casing
stop).

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971