Quoted message said:
Just watch the size of the gaps in tooth count between the cogs.
Presumably your're running somthing like 12-23, the last step being
21-23 or 20-23. If you make that 21-28 or 20-28, that's a real big
jump. Rough on the chain and derailieur, really poor shifting (if
it'll go at all). There's also a big gap in ratio from the 21 to the 28
- I suspect you'll frequently find yourself in a situation where the
45-28 is too low and the 45-21 too high.
Ah, so there is a gap issue too. I didn't know that. I have ordered the
Brandt book from Amazon, but I don't know if it'll cover the cogset
issues. I am running the 12-23, but I also learned I can get a smaller
chainring. That will make a big difference.
Quoted message said:
You could look at mix and matching the casettes to keep the biggest
single jump down to 4 or or 5 teeth, but from what you say about the
current wheelset (suspect rims, old/low quality hubs etc), I'd suspect
that the rear cogs are carrying some significant wear. Look for an
asymmetrical, "hooked" shape to the teeth, indicating significant wear.
If this is the case, your current cassette is both worn and isn't
giving you the range of gear ratios you want. I'd spring for a new
cassette in the right range (about €30-€35 in this neck of the
woods). For a new cassette, I'd get a new chain to match (€15 and up
for somthing reasonable). You're on a budget of course, but a new
cassette and chain can transform the shifting, esp. on an older bike.
In any case, check the chain, cassette and chainrings for wear. Be a
bit careful of a new chain on old cogs, or vice-versa - it may have a
tendency to skip.
I do have some wear on my teeth not only some assemetry but also chips
or chunks out of the teeth. I suppose that may have come from rocks or
sand, but the problem seems to be on the trailing edges too. Clearly the
chain can't have tolerated this without some adverse wear as well.
Curiously, I"m not feeling very money restricted. I only do not wish to
put silly money into a 'black hole' if this bike doesn't work out - but
it does seem to be doing ok by me so far.
When I came out of lurk on this ng, I was 90% convinced I had a bike
which was hopelessly dated. Thus I needed to buy a new bike which I'd
priced at anywhere from U$1k to U$2.5k. The experts here gave me enough
good info that I think I'll stick to this setup for at least a bit
longer thus I have some surplus money to throw at the current ride.
Of course, now that I want to keep this bike, the fellow who owns it (he
lent it to me) seems less than thrilled about selling it. I may end up
with a long term lease of some sort. I'm ok putting money into the bike
even on those terms because I get fair use so think me returning the
bike better than I got it is appropriate.
I have, for example, gotten it to work. When I got it, it had no cables
and then would not shift in the rear outside of the middle three or four
sprockets. The bike shifts "snick-snick" now almost instantly which I
find enormously pleasing. There is no hunting or other delay on the
shift. Move the lever, and without even a tiny wasted bit of pedal
motion, I'm in the next gear.
Being reassured by this group that I"m not riding a laughable POS has
vastly increased my riding enjoyment. Mentals play a huge part in all of
this.
-paul
