Shomano 8 speed cassette question

On Mon, 31 Mar 2003 21:15:37 +0200, Derk Drukker wrote:

That should be Shimano of course....

"Derk Drukker" <[email hidden]> wrote in message
"]news:[email hidden]. nl...

Quoted message said:

Hi!

For an older bike I bought an 8 speed cassette from the

105 group.

Quoted message said:

The cogs are: {13,14,15,16,17,19} , 21, 23.

Codes:
T.V 13T VI, T.V 14T VJ T-15T ZI1, ST-16T Z1, ST-17T

Z1,T-19T Z1 3,

Quoted message said:

ST-21T Z1 3, T-23T Z34.

I would like to take the 14 out and replace it with a 18. I know I need a cog from a
certain series.

Could anybody tell me what code cog I need to keep decent

shifting?

Quoted message said:

MANY TIA! Derk

Just adding a sprocket and getting the correct indexing alignment isn't possible - the 17 and 19 are
already correctly set up to work together. You could file the indexing "splines" on the 18, 19, 21,
and 23 so these can be oriented correctly relative to the 17T - if you do this it doesn't matter
which 18 sprocket you use. But it'll probably work reasonably well with any 18T sprocket without
doing anything.

Not sure I understand the rationale for taking out the 14T and adding the 18T though - you'll end up
with a large gap between the 13 and the 15......

Derk Drukker said:

For an older bike I bought an 8 speed cassette from the 105 group. The cogs are:
{13,14,15,16,17,19} , 21, 23.

Codes:
T.V 13T VI, T.V 14T VJ T-15T ZI1, ST-16T Z1, ST-17T Z1,T-19T Z1 3, ST-21T Z1 3, T-23T Z34.

I would like to take the 14 out and replace it with a 18. I know I need a cog from a
certain series.

Could anybody tell me what code cog I need to keep decent shifting?

They likely never had an 18 in that series. Use any 18 and it will likely shift ok. If it doesn't,
grind down the wide tang on the cog and turn the cog to a position where the HG slot is close to
where it should be on the helix. The HG is not so sensitive in larger cogs.

Grenouil said:

Not sure I understand the rationale for taking out the 14T and adding the 18T though - you'll end
up with a large gap between the 13 and the
15......

I hardly ever use anything in that rang. I make a lot of RPM's and often use that 18, especially
when there's wind and I promise you we get our share of that in Holland!

Thanks!

Derk