On Thu, 3 Jun 2004 06:37:42 +0100, "sparky.g" <[email hidden]>
Quoted message said:Does anyone out there have a Principia bike with problems
shifting between large and small rings at the Front??
This is a question for rec.bicycles.tech. Advertising is the
subject here in rec.bicycles.marketplace.
Quoted message said:rear mech and Bar end shifters. Shifting up to the large
ring at the front is almost impossible. after much grinding
and stopping pedalling it shifts up eventually. ( I don;t
suppose the chain will last long)
I can't imagine how stopping pedalling would help it shift.
Keep pedalling.
Quoted message said:I have had the bike looked at by my local bike shop , who
couldn't get it working (despite having an experienced
mechanic), then by the company I purchased it from (2 hrs
drive away from home). they said they found that the gear
selection cable had pulled through the sheath (and they
replaced the front Mech) and then they sent the bike back,
But it is still the same,
Insist that they make it right. It's absolutely ludicrous
to buy a brand new bike and it can't shift well under
average conditions. You aren't trying to shift into
extreme cross-chained positions (such as big-big and small-
small), are you?
Quoted message said:they did say bar end shifters are not as smooth as STIs. I
figured it was a
This is 100% wrong. Bar-end shifters are optimum for front
shifting; STI is great for the rear. The rear is a precision
application using capable equipment and under little stress;
the front is a caveman-like shove of the tensioned side of
the chain, which also wants easy micro-adjustments --
perfect for bar-end (and other friction-type) shifters.
Anyway, if they really think it should be so difficult to
shift with bar end shifters, they should not sell them.
Quoted message said:problem with the frame and was about the get them to swap
it for a Rexe Pro frame instead (they have bolt on frame
lugs where as the T2 is braised on).
How could frame joint style affect shifting?
Quoted message said:But!! At a race last night I was speaking to someone who
was frustrated and having the same problem with her
Principia, Rexe Pro, with Full Dura-ace all round including
the STi.s
Sounds like you and her both have incompetent mechanics.
Quoted message said:So anyone else have this problem ?? Is it an issue with
Principia frame geometry.
I just looked on the Principia site, and I don't see
anything radical about the geometry.
Quoted message said:Note my £600 Giant with Tiagra components shifts sweet
every time in any situation (even with about 4000 miles on
it), so surely I should expect equal if not better
performance from a new £3000 bike?
You absolutely should, and you should expect quicker, easier
front shifting with bar end shifters.
It's possible that, when they fixed it, it worked for them
on a test-ride. However, you should probably go there,
insist that they fix it, and test-ride it around there
before going home with it.
It sure sounds mostly like the H screw on the front derailer
needs to be adjusted and/or the cable has too much slack.
Assuming it shifts just as badly on a workstand as on the
road, try pulling on the cable itself where it's exposed at
the downtube while pedalling with your other hand. Just pull
the cable away from the downtube. If that works fine, then
it's somewhere between your hand and the shifter.
If that doesn't help, try adjusting the H screw. Then,
pull the cable by hand again; if it works, then try the
shifter. Etc.
Here's some shot-in-the-dark ideas as to what else
could be wrong:
- Incompatible parts (off-brand chain or crank?)
- Bad chainring
- Bad derailer, shifter, or cable
- Cable getting stuck somewhere
--
Rick Onanian