Re: Continuing my front derailleur issues

On Sun, 6 Apr 2025 18:39:04 -0500, AMuzi <am@yellowjersey.org> wrote:
 

On 4/6/2025 11:22 AM, Catrike Ryder wrote:

On Sun, 6 Apr 2025 09:39:23 -0500, AMuzi <am@yellowjersey.org> wrote:
>

On 4/6/2025 9:34 AM, Catrike Ryder wrote:

>
The new Microshift front derailleur is not here yet, but I continue to
get greasy fingers.....
>
Yesterday, I abandoned the new Shimano Tourney derailleur and put my
old Microshift unit back on. Mr. Kunich suggested that I should try
moving it higher on the frame, which I did (thank you Tom).  With the
new 48t sized chain ring guard in place, there was no risk of pushing
the chain over and off the 50T ring.
>
Moving the unit down to where it was just over the 50T ring caused
many problems. With it raised up I was able to get it to shift up
smoothly from the 30T to the 38T. The shift from the 38T to the 50T,
worked now, but was very noisy and rough. It would down shift fine
from the 38T to the 30T, but the downshift from the 50t to the 38T did
not happen. I can achieve that by shifting all the way down to the 30t
and back up to the 38T.
>
It seems the problem is with the 50t chain ring. I have a good 53T
chain ring, which will probably work, but I refuse to be beaten. I
want the 50T dammitall. The new derailleur is supposed to be for a
50-39-30.
>
--
C'est bon
Soloman

>
Front changers have various subtle crimps, bumps and folds
on both plates to hit the chain at specific points depending
on the chainring size and the adjacent ring (which changes
the angle of approach for the chain).  Notably in this case
try a slight bend at the outside front to make it slightly
narrower and more at the bottom edge that at the top.

>
Well OK! I often contemplated that, but my history of the "brute
force" method has more often not worked so well, and it tends to be
difficult to undo.....   BUT if a bicycle expert says to do it, full
steam ahead.
>
...and...  yes!
>
All shifting completes now, at least on the work stand. It's still
seems a bit noisy and hesitant, but the job gets done.
>
Big thanks to Mr. Muzi.
>
I'm still going to install the special 50/38/30 shifter if and when it
gets here, but no more greasy fingers until then.....
>
>
--
C'est bon
Soloman

Since you have more than one front changer handy, look
closely at each plate, inner and outer.  Unlike the 1950s
models:
>
https://forums.bikeride.com/attachment.php?aid=1465
>
Which were simple parallel flat plates, modern changers have
a LOT of engineering; shaping, forming, stamping. It's
subtle but highly effective.

 I have noticed. My old Microshift has a deep concave on the inner
plate to guide the chain onto the big ring. That's why I had to raise
it well above the 50T ring. The Shimano Journey has a similar section,
but it's longer, flatter, and shallower. They both have various sized
bent in lips on the outside plate. I didn't try bending the Journey,
so maybe that would have worked on that one, too.
 The Shimano Journey is shorter and wraps around the rings more than
the Microshift. I see that described as being for road bikes but I
can't find an explanation as to why that's an issue. The new
Microshift says it's road capable. ??? I live and learn.
--
C'est bon
Soloman