STFU TRAIL User manual

COMPATABILITY -CHAIN DAMPERS
The STFU chain dampers wrap around and contain the chain on your mountain bike, limiting how far
it can move when riding over rough terrain. This results in a quieter ride as the chain is no longer
slapping against your frame but also increases chain life by preventing it from flexing sideways,
which can cause the chain to wear and flex too much over time, decreasing shifting performance.
1/2
TRAIL | DH10 | DH07 | DH00
Gearing: The STFU chain dampers are designed to work with 1 X setups only. This means if you
have more than one front chain ring the system will not function as designed. We have
tested using a single larger unit of the TRAIL set with 2X setups (2 front chain rings) and it works
on some bikes. At this stage we only offer each system as a set.
Specific Applications:
•1X gearing for trail bikes up to a 52 tooth cassette - use the TRAIL set
•7 speed DH gearing with cassettes up to 26 teeth - use the DH-07 set
•10+ speed DH gearing with cassettes up to 32 teeth - use the DH-10 set
Fit: The STFU modules attach to the top side of the chainstay. For this reason they are generally
only compatible with bikes that have ‘traditional’ chainstays positioned between the upper
and lower portion of the chain. The modules will generally not work with ‘elevated’ type
chainstays that sit above the chain but some users have been making them work. However, we
take no responsibility if you buy and they do not fit.
•Single speed gearing or 7 speed cassettes up to 21 teeth - use the DH-00 set

You will also need a minimum of 8mm clearance
and a maximum of 60mm clearance between
the chain and the chainstay when in the hardest
gear (smallest cog on cassette) for the STFU to fit.
And there are exceptions. For example, Pole
Bicycles, who we have partnered with to offer
an integrated STFU system on some of their
models, mount one STFU chain damper from
the top.
COMPATABILITY -CHAIN DAMPERS
2/2
TRAIL | DH10 | DH07 | DH00
For advice on the best product for your specific application, please contact STFU Bike via email:
[email protected]
‘TRADITIONAL’
CHAINSTAY WORKS WELL
CHAINSTAY ABOVE CHAIN
GENERALLY WILL NOT WORK
IN
HARDEST
GEAR
DISTANCE BETWEEN
CHAIN & CHAINSTAY
THIS IS THE DH10 SINGLE
MODULE AVAILABLE
IN THE DH10 SET
1/3 1/3

INSTALLATION -CHAIN DAMPERS
In order to make sure your STFU chain dampers are set up correctly, please follow these instructions.
Basic bicycle mechanic skills are required including some basic tools. If you are not confident after
reading these instructions, we suggest getting your local bike shop to install them for you.
The chain should not rub on the STFU chain dampers when pedalling. The dampers should be
positioned so that they are close to the chain in all gears to achieve the best damping but
not so close that rubbing occurs. MINIMUM ZIP TIE WIDTH IS 4.6mm - Thicker is better. Thin zip
ties are not compatible and will result in your dampers going into your spokes.
STFU CONTENTS
1/5
TRAIL | DH10 | DH07 | DH00
Each STFU chain damper kit contains two
damper modules. One is used towards the
front of the chainstay and the other towards
the rear.
Note: Remember to check the zip ties after the
first few rides and tighten as required. They
tend to strech in the sun and need to be
secure. Failure to check tension may result in
your dampers going into the spokes and
being destroyed!
WHAT YOU WILL NEED
FRONT
CHAIN
DAMPER
REAR
CHAIN
DAMPER
REAR
DAMPER FRONT DAMPER
BIKE TYPE
Trail Bike - up to 52T
cassette
DH Bike 7 speed - up to 26 T cassette
DH Bike 10+ speed - up to 32 T cassette
TRAIL-Mini
DH-Mini
DH-Mini
TRAIL
DH07
DH10
x4 200mm Zip Ties that are 5-6mm wide
Thin Zip Ties will not work
Ruler or Tape Measure
Marker Pen or White Out or similar
Sharp Utility Knife
Pliers/Side Cutters
Chain Link Pliers
Single Speed Bike - or up to 21 T cassette DH-Mini
DH-Mini

1. Measure the distance between center of bottom bracket and rear axle. Divide this length by 3.
It should be approx 160mm depending on your bike but exactly 1/3 is the best position.
Make a small mark on the top surface of your chain stay as per images below. Use a non
permanent marker, a piece of tape, white out or chalk or whatever you like. This is
approximately where the STFU chain dampers will be positioned.
2. Shift your bike into the hardest gear (the smallest
cog on your rear cassette). THIS IS IMPORTANT!
STFU INSTALLATION
INSTALLATION -CHAIN DAMPERS
2/5
TRAIL | DH10 | DH07 | DH00
1/3 1/3 MARK
HERE
MARK
HERE
IN
HARDEST
GEAR
3. At the point marked in Step 1 - measure from
the top surface of your chain stay to the bottom
of your chain, directly above this point.
NOTE: Round your measurement up to the
nearest 5 mm increment. For example, if you
measure 22 mm - round this up to 25 mm. You
can trim more off later if required once you trial
fit the damper. It will be a lot more difficult to
make it longer if you cut it too short! POINT MARKED IN STEP 1
MEASURE TO UNDERSIDE
OF CHAIN
MEASUREMENT WOULD
BE 25MM

5. Position the quick link on your chain above
your chain stay. Break the chain and insert the
chain through your STFU chain damper and
then re-connect your quick link.
Only tighten the cable tie slightly so you can
still move and slide the STFU damper along the
chain stay.
If you have rounded or curved chainstays use
the included end caps for a more secure fit
Repeat steps 2 to 7 for the front damper module
or you can do them both at the same time.
CUT THE LINE CLOSEST
TO THE MEASUREMENT
USE ONLY 1 ZIP TIE FOR
NOW AND DO NOT
TIGHTEN JUST YET...
4. Trim the STFU chain damper as required - measurements are marked on the back of the
damper. For example, we measured 22 mm in the steps above so locate the 25 mm mark on the
STFU damper and trim it there. The line closest to the measurement you want is the line to cut at.
We have included the clearance in the design so you don’t have to think about that.
Guide lines are included to help you make a nice straight cut. The TRAIL units have a hard plastic
inner skeleton that can be difficult to cut, so make sure you have a sharp blade. Position as shown
below and rock the knife back and forth with firm pressure. Use a cutting board underneath.
INSTALLATION -CHAIN DAMPERS
3/5
TRAIL | DH10 | DH07 | DH00
6. Using one zip tie, position the STFU damper
where you made the mark in step 1.

8. If the chain is rubbing in the hardest gear and
sliding the STFU towards the cranks (10 mm or so)
doesn’t fix this then trimming the height of the
STFU by 5mm may be required. Before doing so,
make sure there is sufficient room between the
chain and the top of the STFU when in the easiest
gear (biggest cog) - you may need to move the
location of the STFU closer to the cranks to
accommodate this.
Note: Take care when trimming the STFU damper
modules, we have been able to join cut seg-
ments together using additional cable ties when
we have cut them too short but this is not an ideal
solution.
WHEN IN HARDEST GEAR,
THERE SHOULD BE A SMALL
AMOUNT OF CLEARANCE
WHEN IN EASIEST GEAR,
THERE SHOULD BE A SMALL
AMOUNT OF CLEARANCE
MOVE DAMPER CLOSER
TOWARDS CRANKS TO
INCREASE CHAIN CLEARANCE
7. Shift your bike through your entire range of gears taking note of the top and bottom most gears.
Modify the position of the STFU so the chain does not rub on the STFU in any position. Having a bike
stand or partner for this will make the job a lot easier.
Sliding the STFU forward towards the cranks will generally give more room for the chain and sliding it
away from the cranks will give less.
The key is to position the STFU so it is just far enough away from the chain in all gears that it does not
rub. The closer it is to the chain, the better damping it will provide so you want to spend some time
making sure it is adjusted correctly.
For dual suspension bikes, also check clearance with the suspension at normal sag. This should be
done whilst sitting on your bike in full riding kit. Some suspension designs can result in the chain
moving relative to the STFU module as the suspension compresses. You need to make sure it's not
rubbing the top or bottom when pedalling, otherwise the unit will wear unnecessarily which could
lead to failure.
Failure to set up your dampers properly is not covered by warranty.
INSTALLATION -CHAIN DAMPERS
4/5
TRAIL | DH10 | DH07 | DH00

9. Once you are happy with the position of your
STFU damper, add the additional cable tie to
properly secure the unit to your frame. We like to
position the cable tie heads on the underside or
even back side of the chainstay so they are
not seen. Important: Use a pair of pliers to really
tighten the cable ties up so the dampers are as
secure as possible.
Note: Zip ties tend to stretch slightly after being
in the sun - this can allow your dampers to
rotate into the spokes which can destroy them.
Make sure you check zip tie tension after the
first few rides and tighten them as required.
After this they should be fine for the season but
its a good idea to check them every now and
then.
Leave a little extra length on the zip ties
when trimming to enable a pair of plyers to
be attached.
10. check alignment by shifting your bike through
the full range of gears and inspect everything
is still positioned as it should be.
11. Go shred on your newly quiet bike!
INSTALLATION -CHAIN DAMPERS
5/5
TRAIL | DH10 | DH07 | DH00
MOUNT DAMPER
CENTRAL TO
CHAINSTAY
MOUNTING LIKE THIS IS
UNSTABLE & NOT
RECOMMENDED
Note: The ideal position for your dampers is
central to your chainstay. This will result in the
most stable mounting. If you have to mount the
module off the side of the chainstay to prevent
chain rub then it will not be stable and is likely
to flex under impact forces AND end up in the
spokes.
We have tried to accomodate as many
frames as possible with the design, however,
there will be some frame/gearing combo's that
are simply not compatible. Using just one
module may be the only solution and one still
works well. Feel free to get in touch to discuss.