Painful chain slip/ghost shift/???? problem

I have a 55cm Litespeed Natchez frame, Campy Racing T crankset of
8 speed vintage with the original rings, 9 speed upgrade with less than 3000
miles on the cogs, and less than 1/16" inch (maybe 2/3 that - my ruler doesn't
have finer gradations) chain stretch on 12" of chain (installed at the same
time as the cogs).

I weigh 150 pounds and have a backpack + laptop + lock combination that
can't add over 15 pounds. Think spindly computer geek not clydestale.

In the last week I've stood up twice (once accelerating on flat ground, once
going up a hill), had the cranks spin forward, and crashed. OW. It's never
done this before.

What's going on?

--
a href="http://www.poohsticks.org/drew/"Home Page/a
Life is a terminal sexually transmitted disease.

On Wed, 8 Sep 2004 18:59:45 -0600, (Drew
Eckhardt) wrote:

In the last week I've stood up twice (once accelerating on flat ground, once
going up a hill), had the cranks spin forward, and crashed. OW. It's never
done this before.

It it happened while using he 42t ring on the racing T, the ring may
be worn. Replace the chain and ring. The 42 ring for a triple is
costly. A 42 for a double, w/o shift assists works fine too. If you
want to save $, Vuelta may have a 42 x `35 bolt pattern. Sometimes,
rotating the middle ring 90 degrees will solve your problem for a
while.

On Wed, 8 Sep 2004 18:59:45 -0600, (Drew
Eckhardt) wrote:

In the last week I've stood up twice (once accelerating on flat ground, once
going up a hill), had the cranks spin forward, and crashed. OW. It's never
done this before.

It it happened while using he 42t ring on the racing T, the ring may
be worn. Replace the chain and ring. The 42 ring for a triple is
costly. A 42 for a double, w/o shift assists works fine too. If you
want to save $, Vuelta may have a 42 x `35 bolt pattern. Sometimes,
rotating the middle ring 90 degrees will solve your problem for a
while.

On Wed, 8 Sep 2004 18:59:45 -0600, (Drew
Eckhardt) wrote:

In the last week I've stood up twice (once accelerating on flat ground, once
going up a hill), had the cranks spin forward, and crashed. OW. It's never
done this before.

It it happened while using he 42t ring on the racing T, the ring may
be worn. Replace the chain and ring. The 42 ring for a triple is
costly. A 42 for a double, w/o shift assists works fine too. If you
want to save $, Vuelta may have a 42 x `35 bolt pattern. Sometimes,
rotating the middle ring 90 degrees will solve your problem for a
while.

"Drew Eckhardt" wrote in message
...
I have a 55cm Litespeed Natchez frame, Campy Racing T crankset of
8 speed vintage with the original rings, 9 speed upgrade with less than
3000
miles on the cogs, and less than 1/16" inch (maybe 2/3 that - my ruler
doesn't
have finer gradations) chain stretch on 12" of chain (installed at the
same
time as the cogs).

I weigh 150 pounds and have a backpack + laptop + lock combination that
can't add over 15 pounds. Think spindly computer geek not clydestale.

In the last week I've stood up twice (once accelerating on flat ground,
once
going up a hill), had the cranks spin forward, and crashed. OW. It's
never
done this before.

What's going on?

My chain did that to me three times up an 8% grade before it finally broke.
One of the plates popped off the pin. My guess is that the plate was
bulging before it came right off, and that's why it kept coming off the
chain ring. Luckily a guy behind me had a chain tool.

"Drew Eckhardt" wrote in message
...
I have a 55cm Litespeed Natchez frame, Campy Racing T crankset of
8 speed vintage with the original rings, 9 speed upgrade with less than
3000
miles on the cogs, and less than 1/16" inch (maybe 2/3 that - my ruler
doesn't
have finer gradations) chain stretch on 12" of chain (installed at the
same
time as the cogs).

I weigh 150 pounds and have a backpack + laptop + lock combination that
can't add over 15 pounds. Think spindly computer geek not clydestale.

In the last week I've stood up twice (once accelerating on flat ground,
once
going up a hill), had the cranks spin forward, and crashed. OW. It's
never
done this before.

What's going on?

My chain did that to me three times up an 8% grade before it finally broke.
One of the plates popped off the pin. My guess is that the plate was
bulging before it came right off, and that's why it kept coming off the
chain ring. Luckily a guy behind me had a chain tool.

"Drew Eckhardt" wrote in message
...
I have a 55cm Litespeed Natchez frame, Campy Racing T crankset of
8 speed vintage with the original rings, 9 speed upgrade with less than
3000
miles on the cogs, and less than 1/16" inch (maybe 2/3 that - my ruler
doesn't
have finer gradations) chain stretch on 12" of chain (installed at the
same
time as the cogs).

I weigh 150 pounds and have a backpack + laptop + lock combination that
can't add over 15 pounds. Think spindly computer geek not clydestale.

In the last week I've stood up twice (once accelerating on flat ground,
once
going up a hill), had the cranks spin forward, and crashed. OW. It's
never
done this before.

What's going on?

My chain did that to me three times up an 8% grade before it finally broke.
One of the plates popped off the pin. My guess is that the plate was
bulging before it came right off, and that's why it kept coming off the
chain ring. Luckily a guy behind me had a chain tool.

drew- In the last week I've stood up twice (once accelerating on flat ground,
once
going up a hill), had the cranks spin forward, and crashed. OW. It's never
done this before. BRBR

Suspect something is amiss in your rear hub freehub. The pawls are not
engaging, causing the whole thing to not engage. Need to take apart, analyze
the freehub.

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"

drew- In the last week I've stood up twice (once accelerating on flat ground,
once
going up a hill), had the cranks spin forward, and crashed. OW. It's never
done this before. BRBR

Suspect something is amiss in your rear hub freehub. The pawls are not
engaging, causing the whole thing to not engage. Need to take apart, analyze
the freehub.

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"

drew- In the last week I've stood up twice (once accelerating on flat ground,
once
going up a hill), had the cranks spin forward, and crashed. OW. It's never
done this before. BRBR

Suspect something is amiss in your rear hub freehub. The pawls are not
engaging, causing the whole thing to not engage. Need to take apart, analyze
the freehub.

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"