15
14
F.A.Q
My fork leaks when I connect my hugh pressure pump,
what should I do ?
Check with a Schrader valve core remover that the valve
bush is screwed on correctly.
My fork has nega�ve travel, is this normal?
The BOS air spring is designed to lower the engagement
threshold as much as possible. Therefore, it is possible on
some bikes that there will be a small nega�ve travel.
Where can I buy replacement s�ckers or a valve cap?
These items and more are available in our online store.
My new fork has bushing play, what should I do?
The unique bushing alignment and tolerance on BOS forks
results in less fric�on, more sensi�vity, and some bushing
play from the factory. If the bushing play feels abnormall
y
excessive, please contact a BOS service center for help.
My fork is lowering as I deflate it, what is happening?
When you deflate the fork by the Schrader valve, you are
only emptying the posi�ve air chamber. The nega�ve air
chamber stays under pressure and exerts an opposing force
on the air piston and pulls the fork down. To avoid this
phenomenon, make sure your fork is fully relaxed when
defla�ng, then slowly deflate your fork with your high
pressure pump.
I just inflated my fork for the first �me and it is really hard,
what can I do?
Have you changed the se�ngs of the fork? Check that the
se�ngs are s�ll close to our recommenda�ons in the user
manual of your product.
If the problem persists, the fork may have residual pressure
from produc�on. Slide a thin plas�c cable �e (Rilsan type)
between the wiper seals and the plungers un�l the air is
released. Adjust the air pressure again.
If your fork is s�ll hard, please contact our service
department at [email protected].
Remember to balance the air spring
I have about 5mm of travel unused when I ride normally.
Our forks are designed to be very progressive at the end of
travel to give you a bo�omless feeling. This means that
those last couple millimeters of travel might only be used on
the biggest hits or when you case a landing. You can think of
them as insurance to get you out of the trickiest situa�ons.
If you have more than about 5% of your travel unused, try
lowering your air pressure by 5PSI and check your
compression se�ngs. If your compression se�ngs are much
harder than our recommended values, try bringing them
closer to the base se�ngs in your product’s user manual.
I have grease/oil coming out of my brand new fork seals.
This is not unusual at the beginning of the life of a fork. Clean
off the stanchions and the seals and it will stop a�er a few
rides.
My fork has been si�ng for a couple of weeks and some oil
came out of the seal when I rode it the first �me.
BOS seals can let out a li�le bit of oil when they have been
si�ng and dried out. Wipe off any oil, and none more will
come out when the seal is lubricated again.
I have grease/oil coming out of my well-ridden fork seals.
It’s �me for a service! Contact your nearest BOS authorized
service center for a full service.
But I haven’t reached your recommended service interval
yet.
Our recommended service intervals cannot cover 100% of
customer’s usage cases. Use in wet, muddy condi�ons;
storage out in the sun; frequent use; or improper care can all
cause your seals to wear out more quickly.
Where can I find my serial number ?
The serial number is engraved under the steer tube, it’s
composed of 7 numbers.
How to set the FCV?
The FCV is a factory preset internal system.
How to set the oil height :
-
Push the stanchion all the way down
-
Li� the hydraulic sha� all the way up
-
Measure the height between the top of the stanchion and the top of the oil with a clean
ruler
For any other information, you can send us your request by sending a message to
[email protected]..
3.2 Oil level
Idylle 39 Oil level
You can find below the oil levels used for your fork services.
Oil type
Idylle 39 FCV
Hydraulic side (right)
BIOIL
220mm / 400ml
Air side (left)
AMX6
40 ml
MAINTENANCE
It is strongly recommended to use BOS AMX6 for lubrica�on and BOS BIOIL oil for the closed cartridge.
Changing the type of oil risks changing the fork’s performance and reducing the life of wear parts.
The lubrica�ng oil on the air side must be inserted into the fork leg and not into the air stem.
