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Shimano Dual SIS 7 speed (photos)



 
 
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  #21  
Old February 24th 16, 04:16 AM posted to rec.bicycles.tech
Emanuel Berg
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Posts: 318
Default Shimano Dual SIS 7 speed (photos)

Frank Krygowski writes:

Have you tried using the Park Tool website?
[...]
http://www.parktool.com/blog/repair-...eur-adjustment


Man, the scope of that article makes me understand why
you didn't feel like explaining this yourself...

--
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  #22  
Old February 24th 16, 04:24 AM posted to rec.bicycles.tech
Emanuel Berg
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Posts: 318
Default Shimano Dual SIS 7 speed (photos)

Frank Krygowski writes:

http://www.parktool.com/blog/repair-...eur-adjustment


If anyone like me likes to print that I did some
formatting. Does not include the pictures, of coures.

What Tools do I need?

* Repair Stand: holds bike secure for easy work.
* Hex wrenches as needed.
* Screwdriver (#2 Phillips or straight blade)
* Light liquid lubricant
* Derailleur cable inner wire and housing as needed
* Caliper or metric ruler
* Cable end caps and housing end caps as needed
* Rags

The front derailleur simply shoves the chain off one
front chain ring and onto another ring. The cage
surrounding the chain is pulled in one direction by
the inner wire. A spring in the derailleur returns the
cage to the other direction when the inner wire is
relaxed. A properly adjusted front derailleur should
shift the chain between the front chainrings but will
not throw the chain off the rings. The basic
adjustments for the front derailleur are the height,
rotation, limit screws and inner wire tension (index
setting).

It is generally a good idea to lubricate the pivot
point of the front derailleur with a light lubricant.
The cable inner wires should also be lubricated.
If you have loosen the inner wire pinch bolt,
lubricate those threads as well. When tightening this
pinch bolt, secure to approximately 30-40 inch-pounds.
This is about 10 pounds of effort hold a wrench 3
inches from the bolt.

2

Front Derailleur Height

Before checking limit screw adjustments, check the
derailleur positioning. If the derailleur cage is too
far above the large chainring, it is more likely to
shift poorly. If the derailleur is too low, it may
scrape against the chainrings or jam the chain
when shifting.

Some front derailleur models do not have height or
rotation adjustments. These models mount on a plate
and both height and rotation settings are preset.
Additionally, some bikes have a bracket commonly
referred to as a “braze-on” for front derailleur
mounting. This bracket will allow limited height and
rotational settings.

1. Inspect height alignment of front derailleur.
The outer cage plate must be positioned over the
largest chainring when viewing height. Simply grab
the exposed front derailleur inner wire until
outer cage plate is directly over outer chainring
teeth. Use care to not shift the derailleur cage
past this point. Note height and direction of
change needed. It is then necessary to relax the
cable to loosen the mounting bolt and raise or
lower the height as needed.

2. The gap between the teeth of the outer chainring
and lower edge of the outer cage plate should be
1-2mm, about the thickness of a penny.
Using a penny or a dime as a feeler gauge, fit it
between the chainring teeth and the cage plate.
It should just fit between the teeth and plate.

3. To lower cage, release inner wire tension
completely by shifting to innermost chainring.
Note angle of outer cage plate relative
to chainring.

4. Front derailleur clamps typically leave a mark on
the frame, which is useful as a reference when
changing height. Loosen derailleur clamp bolt,
change derailleur height, and return cage to same
rotation relative to chainring. Tighten clamp
bolt. Move outer cage plate over outer chainring,
and check height again. Repeat this process until
cage plate height is 1-2mm above outer chainring.

3

Front Derailleur Rotational Angle

The front derailleur cage should be approximately
parallel to the chain. If the derailleur cage is
rotated too far from this position, it will shift
poorly. If the derailleur mount is a clamp type, its
rotation can be changed. Generally, the outer cage of
the front derailleur should be aligned to the chain.
Image C below shows adequate alignment.

Derailleur A is rotated too far counter-clockwise.
Derailleur B is rotated too far clockwise. Notice rear
end of cage is inward, toward mid bike plane.
Derailleur C is acceptably aligned.

1. Shift chain to outermost chainring and outermost
rear sprocket.

2. Sight chain from directly above chainrings.
Consider the chain as representing a straight
line. Compare this line to outer derailleur cage
plate. Outer cage plate and chain should be
parallel. Keeping the cage and chain parallel will
minimize the risk of the chain jumping off the
outermost ring. If cage is not parallel, there
will be a relatively large gap at either the back
or the front end of the cage, and the chain may
over shift.

3. If derailleur cage needs to be rotated, note
direction of desired rotation.

4. Release inner wire tension by shifting to the
innermost chainring.

5. Many clamps leave a slight marking on the frame.
Use this scarring as a reference when changing
height. It is also possible to use a pencil to
make two reference marks on the frame, one for
height and a second, vertical mark, to reference
rotation. Use the marks to avoid inadvertently
changing height.

6. Loosen clamp bolt and slightly rotate in correct
direction. Use care not to change height.
Tighten derailleur clamp bolt.

7. Shift to outer chainring and observe rotation
alignment. Repeat adjustment if necessary.

NOTE: Some front derailleur models do not have height
or rotation adjustments. These models mount on
a plate and both height and rotation settings
are preset. Additionally, some bikes have
a bracket commonly referred to as a “braze-on”
for front derailleur mounting. This bracket will
allow limited height and rotational settings.

4

Limit Screw Settings

Limit screws stop the inward and outward travel of the
front derailleur cage. Limit screws are marked “L” and
“H.” The L-screw will stop the motion of the
derailleur toward the smallest chainring. The H-screw
will stop the motion of the derailleur toward the
largest chainring.

If the limit screws lack any marking, you will need to
determine which are the “H” and “L” by testing.
Begin with the chain on the smallest cog. Relax the
cable tension completely using the cable barrel
adjuster. Place a hand on the derailleur body to feel
for any lateral motion, and select one screw to turn
one full turn clockwise and then counter-clockwise.
If you felt motion in the derailleur, this is the “L”
screw. If there was no motion, do the same test with
the other limit screw. You should consider marking the
“L” screw permanently. The other screw by default is
the “H” screw.

Although the limit screws will stop the derailleur, it
is the inner wire and derailleur spring that make the
derailleur move. If the inner wire has too much
tension, the derailleur will not rest on the L-screw
stop. If the inner wire tension were to change, the
derailleur inner limit would also change, possibly
causing the chain to fall off the rings.

5

L-Screw Adjustment

The L-screw controls the inward most travel of the
front derailleur. Set adequately, it allows the chain
to shift to the smallest ring, but not beyond so it
falls off.

1. Shift chain to innermost rear sprocket and
innermost front chainring. Inspect derailleur for
marking indicating “L” screw.

2. Check inner wire tension. It should be fairly
loose at this time. If inner wire is taut, turn
barrel adjuster clockwise into housing. The barrel
adjuster is typically located where the cable
housing enters the shift lever. If barrel adjuster
is already fully turned into housing, loosen inner
wire pinch bolt, slacken inner wire and
retighten bolt.

3. Sight gap between inner chain plate and inner cage
plate. Only a small gap should be visible, about
1/16" or 1mm, about the thickness of a dime.

4. Pedal bike slowly and continue to sight gap.
Set clearance at tightest point in chainring
rotation. Adjust L-screw so there is a small gap
between inner cage and inner chain plate.
Pedal bike and check that chain is not rubbing
cage as chainrings turn.

+ If there is no gap and chain is rubbing cage,
loosen L-limit screw 1/8 turn
(counter-clockwise). Inspect for gap again and
repeat until slight gap appears.

+ If the gap appears larger than 1mm at its
widest point, tighten the L-screw, in small
increments, until the gap closes.

5. Test the shift by shifting chain to next chainring
then shift back to the innermost ring. Do not use
the shift lever. Pull on the inner wire to shift
the derailleur. Using the lever may confuse limit
screw issues with cable tension issues. If chain
shifts quickly, limit screw setting is adequate.

6. If the shifting appears is slow (requires more
than one pedal revolution to initiate shift), turn
L-limit counter-clockwise 1/8 turn and repeat
test. Repeat 1/8-turn increments until shifting is
adequate. The gap will open wider than the 1mm
target, but will still be as small as possible
with adequate shifting.

7. If chain is shifting beyond the inner ring and
falls off the chainring, gap may be too large or
cage alignment may be off. Tighten L-screw 1/8
turn and check shift again. If chain ends up
rubbing inner cage of derailleur, yet still drops
off inner ring when shifting, other problems such
as chain line or derailleur rotation exist.

6

H-Screw Adjustment

The outward travel of the front derailleur is stopped
by the H-screw. When viewing the H-limit adjustment,
make sure there is enough tension on the inner wire by
either keeping extra pressure on the lever, or by
pulling the exposed inner wire taut by hand. Use a rag
to protect your hand if pulling the inner wire.
After the H-screw is adjusted the inner wire should be
re-tensioned to assure proper shifting.

1. Shift to outermost sprocket in rear and outermost
front chainring. Inspect derailleur for mark
indicating H-screw.

2. Pull inner wire with hand to increase tension to
insure derailleur is against H-screw.

3. Maintain full pressure on inner wire and check gap
between chain and outer cage plate. Only a small
gap should be visible, about 1/16" or 1mm.
Pedal bike slowly and continue to sight gap.
Set clearance at tightest point in
chainring rotation.

+ If chain is rubbing cage, loosen H-screw 1/8
turn and pull fully on inner wire.
Check gap again.

+ If chain is not rubbing, tighten H-screw
repeatedly until chain is 1mm

4. Test shift to the large ring. Shift derailleur
from next to largest to largest ring using hand
pressure on inner wire rather than shift lever.
If shifting is slow, loosen H-limit screw slightly
and repeat test. If chain shifts off the outside
of the large chainring, the outer-limit is set too
loose. Tighten H-screw limit and test shift again.

7

Index Adjustment—Three Chainring Bikes

Some front derailleur systems have an index setting.
If the shift lever has three distinctive stops or
clicks, it is an index shifter. If the front shift
lever is friction, there is no index setting. If the
front shift lever has multiple clicks, such as some
twist grip style shifters, it is shifted similar to
friction levers. Set indexing only after completing
all adjustment above.

1. Shift chain to middle chainring in the front and
innermost rear sprocket.

2. View gap between inner cage plate and chain.
Gap should be as small as possible without
rubbing chain.

3. To reduce gap, increase inner wire tension by
turning barrel adjuster counter-clockwise.
Adjusting barrel may be on frame or on shift
lever. Check gap again.

4. If chain is rubbing cage, turn barrel adjuster
clockwise, or inward toward shifter body.

5. If barrel adjuster is all the way in or out there
will be no adjustment possible. In these cases
reset the barrel. Shift to innermost chainring and
loosen inner wire pinch bolt. Turn the barrel
fully clockwise and back out about 2 full turns.
Pull wire gently with fourth-hand tool and tighten
pinch bolt. Begin adjustment of inner wire tension
as above.

6. Test shift of front derailleur to all three front
chain rings. If the derailleur rubs in the largest
front chainring, double check H-limit screw and
inner wire tension, which may be too loose.
If chain is slow to shift to smallest chainring,
double check L-limit screw and inner wire tension,
which may be too tight.

8

Index Adjustment—Two Chainring Bikes

Some front derailleur systems have an index setting.
If the shift lever has two distinctive stops or
clicks, it is indexing. If the front shift lever is
friction, there is no index setting. NOTE: Some bike
uses an “in-line” barrel adjuster to change housing
length and set the indexing.

1. Shift chain to outer chain ring in the front and
outermost rear cog.

2. View gap between outer cage plate and chain.

3. If outer cage plate clears chain, index setting
is adequate.

4. If plate is rubbing chain, increase inner wire
tension by turning adjusting barrel
counter-clockwise and check again.

5. If barrel adjuster is all the way in or out there
will be no adjustment possible. In these cases
reset the barrel. Shift to innermost chainring and
loosen inner wire pinch bolt. Turn the barrel
fully clockwise and back out about 2 full turns.
Pull wire gently with fourth-hand tool and tighten
pinch bolt. Begin adjustment of inner wire tension
as above.

6. Test shift of front derailleur to both
front chainrings.

9

Front Derailleur Performance

The front derailleur should shift the chain between
chainrings without throwing the chain off the extreme
outer and inner rings. It is possible that the front
derailleur will rub the chain slightly even on
properly adjusted bikes. This is likely on some bikes
when riding in the largest sprocket in front and the
smallest cog in back. As the bike is pedaled with
force the frame flexes and moves the chainrings side
to side, which cause an intermittent rubbing noise.
Loosening the H-limit would move the front cage out
more, and may stop the rubbing, but it may also cause
the chain to shift over the largest ring and come off.
If all aspects of front derailleur adjustments are
correct on this bike, the rider is simply exceeding
the engineering and design capabilities of
the machine.

--
underground experts united
http://user.it.uu.se/~embe8573
  #23  
Old February 25th 16, 12:27 AM posted to rec.bicycles.tech
John B.[_6_]
external usenet poster
 
Posts: 2,202
Default Shimano Dual SIS 7 speed (photos)

On Wed, 24 Feb 2016 03:07:44 +0100, Emanuel Berg
wrote:

Emanuel Berg writes:

However here the easy stuff ends. Is there some
method to what to do next? I thought I'd figure it
out because the combinations seemed limited what to
do. However I didn't succeed. On both front and
back, either the wire gets ridiculously loose (like
a loop) *or* I gets so heavy I have to put
considerable strength into getting to the next step.
Not possible to do while riding the bike!


OK, I got it working! With a tight wire it is possible
to shift when pedaling (with the legs). I don't know
if that is normal or if it is still a bad sign it
can't be done with just a little force to it.

I discovered two little screws (PZs) on the front
mechanism. It says H on the left and L on the right.
The "H" is perhaps "horizontal" (?) because it moves
the arm between the saddle frame pole and the
chainwheels. Actually you can align the arm pretty far
to the right this way. Is there a method to this?
I understand the purpose but it wasn't the easiest
thing to detect a good position or tell a good one
from a bad (save for when the chain came off).

The L screw tho I didn't see anything happening.
What does it do?


Actually the "H" and "L" stand for "High" and "Low" and are the stop
screws that limit the travel of the derailer so that the chain doesn't
come off the sprocket(s).

Shimano publishes very complete documentation for their equipment so
you can try http://si.shimano.com/ and search out your specific
shifter and derailer and go from there.
--
cheers,

John B.

 




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