Shifting problems

Chris Nelson wrote:
On May 15, 7:21 pm, Michael Warner wrote:
On 15 May 2007 10:05:24 -0700, Chris Nelson wrote:

So I picked up a used tandem (Trek T900) and its a hoot but it has
some rear shifting problems. More specifically, when shifting the
chain momentarily sits on top of the cogs before settling in, creating
a temporary cadence increase. Once shifted, it runs fine. It happens
on up and downshifts, and I believe to have it adjusted correctly as
far as indexing, because it shifts flawlessly in the workstand. It
only has problems under load.
IME a bike which shifts perfectly on the stand but badly under load
has an over-worn chain and/or cluster. Try replacing the chain, but
you'll probably also have to replace the cluster.

--
Home page:http://members.westnet.com.au/mvw

I just ordered an SRAM PC-68 8SP CHAIN, maybe that will go better with
the cog that's on there. Everything else seems to be in order(thanks
everyone for the input). If that doesn't do it, I'm thinking of going
to all 9-speed stuff instead of the mix that's on there now. This
would also allow me to upgrade to higher level components such as XT.
The rear hub that is on there is a no name. If it takes an 8-speed
cog, should it be able to take a 9-speed cog? Or might I run into a
problem there?

Your present equipment can be nine speed, changing only the shifter,
chain and cassette ( hub and both gear changers are all nine compatible)
if that turns you on. I suspect from your description there are setup or
alignment issues, not the number of cogs, at the root of your gear train
problems.

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

On May 17, 12:42 am, A Muzi wrote:
Chris Nelson wrote:
On May 15, 7:21 pm, Michael Warner wrote:
On 15 May 2007 10:05:24 -0700, Chris Nelson wrote:

So I picked up a used tandem (Trek T900) and its a hoot but it has
some rear shifting problems. More specifically, when shifting the
chain momentarily sits on top of the cogs before settling in, creating
a temporary cadence increase. Once shifted, it runs fine. It happens
on up and downshifts, and I believe to have it adjusted correctly as
far as indexing, because it shifts flawlessly in the workstand. It
only has problems under load.
IME a bike which shifts perfectly on the stand but badly under load
has an over-worn chain and/or cluster. Try replacing the chain, but
you'll probably also have to replace the cluster.

--
Home page:http://members.westnet.com.au/mvw

I just ordered an SRAM PC-68 8SP CHAIN, maybe that will go better with
the cog that's on there. Everything else seems to be in order(thanks
everyone for the input). If that doesn't do it, I'm thinking of going
to all 9-speed stuff instead of the mix that's on there now. This
would also allow me to upgrade to higher level components such as XT.
The rear hub that is on there is a no name. If it takes an 8-speed
cog, should it be able to take a 9-speed cog? Or might I run into a
problem there?

Your present equipment can be nine speed, changing only the shifter,
chain and cassette ( hub and both gear changers are all nine compatible)
if that turns you on. I suspect from your description there are setup or
alignment issues, not the number of cogs, at the root of your gear train
problems.

--
Andrew Muziwww.yellowjersey.org
Open every day since 1 April, 1971- Hide quoted text -

- Show quoted text -

I guess what is bothering me is that the derailleur is a 9 speed, but
the chain, cog and shifter is 8 speed.

I went through your list of stuff to check, and everything seems to be
in order, so I'll have to wait on that new chain and give that a shot.

Chris