DynAccess Hydra Monoski User manual

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DynAccess Ltd
301 Broadway STE 114
Bethlehem, Pennsylvania 18015
USA
[e-mail] –tel. [phone]
Hydra Monoski
Owner’s Manual
Version 2021-22
Table of Contents
Introduction……………………...2
Safety First…………………………2
General Description……………4
Instructions…………………………6
Mounting the Seat…………6
Mounting Bindings………..7
Installing Monoski………….7
Sitting in the Seat ………….8
Adjusting the Foot Rest… 9
Buckling Your Belt………….9
The Shock……………………..12
Using the Lift………………..13
Evacuation…………………….15
Maintenance and Service….15
Warranty…………………………..16

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Introduction
Safety First
Thank you for purchasing a DynAccess Hydra monoski. We appreciate your business and are
committed to providing you with not only a quality product, but also excellent service. The
following pages will provide you with basic information for your new monoski. Upon receiving
your monoski, read the information below and become familiar with your monoski.
Warning!
It is essential that you read this manual and fully understand your new monoski and its features
before using it. Please pay special attention to the safety information and cautions to help you
reduce the risk of serious injury. If you have any questions or do not understand something,
please contact DynAccess directly.
Note: This manual is not intended as a comprehensive use, service, repair or maintenance
manual. Please contact DynAccess for all service, repairs or maintenance.
Disclaimer: DynAccess Ltd is not responsible for any damages to you or others arising from
riding, transporting, or other use of your DynAccess monoski. In the event that your monoski
breaks or malfunctions, DynAccess shall have no liability beyond the repair or replacement of
your monoski pursuant to the terms outlined in the warranty provisions of this manual.
Warning!
Like any sport, riding a monoski involves risk of injury and death. By deciding to ride a monoski,
you assume the responsibility for that risk. In order to reduce that risk, we strongly urge you to
read and follow the safety information and cautions in this manual.
Please note that it is impossible to anticipate every situation or condition that can occur while
riding a monoski. This manual makes no representation about the safe use of your monoski
under any condition. There are risks associated with the use of any monoski which cannot be
predicted or avoided, and which are the sole responsibility of the monoskier.
1. Correct Fitting
➢Make sure that your monoski fits correctly to your body, riding style and riding
conditions. If your monoski does not fit properly, it increases the risk that you
may lose control. Making the proper adjustments to your monoski requires
experience and skills. If you are unsure about how to adjust your monoski, we

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recommend you take it to a specialized workshop or contact us directly before
riding.
➢For fitting you in the bucket seat, see p.9
➢For footrest adjustment, see p.9
➢For adjusting the center of gravity, see p.8
➢For adjusting the ride height, spring rate, rebound and compression damping,
please see the separate Shock Manual.
2. Mechanical Safety Check
➢Routinely check the condition of your monoski before each use (e.g. loose bolts
and nuts, cracks, fraying straps, etc.).
➢In tightening the fasteners (e.g. nuts, bolts, and screws) on your monoski, use
correct tightening torque. Incorrect tightening torque can result in component
damage or failure.
➢Make sure that the tri-glides used for non-sewn side-release buckles prevent the
belts from slipping out of the buckles.
➢Check the condition of the shock absorber for any visible damage and oil
leakage.
➢Check the rebound and compression damping of the shock absorber.
3. General Safety on the slope
➢Spend considerable time and effort to learn how to get on a chairlift, to sit on it
safely, and to get off safely. Some chairlift seats are very thick and lead to you sit
closer to the edge. Make sure you sit in a stable and secure manner without any
risk of falling off. See “Using the Chairlift” section of this manual for details.
➢If you are a beginner and/or are not familiar with ski slopes, always ski with a
certified instructor.
➢If you ride the monoski independently, make sure that you have enough
knowledge and skills to ride it safely and under full control at all times.
➢Ski on properly prepared ski slopes.
➢Observe the rules on the slopes.
➢Always wear a helmet which meets the latest certification standards and is
appropriate for the type of skiing you do.
➢Always wear ski gloves and goggles.
➢Start slowly on easier terrain and build up your skills.
➢Be familiar with how your suspension works as it changes the way your monoski
performs.
➢Avoid skiing alone.
➢Avoid riding the lift alone.
➢If you want to adjust the shock absorber on the slope, find a relatively flat place
where there is no heavy traffic.
➢Ride at speeds appropriate for the conditions. Higher speed in general means
higher risk.

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➢Ride defensively and always under full control.
➢Always assume that others do not see you.
➢Don’t do stunts or jumps.
➢If you intend to do stunts or jumps with your monoski despite our advice not to,
think carefully about your skills before deciding to take the large risks involved
with this kind of riding.
➢Avoid riding in bad weather, at night, and anytime when visibility is limited.
➢Pay attention to the snow conditions, which affects your ride significantly.
National Ski Areas Association “Your Responsibility Code”:
DynAccess is a member of the Rehabilitation Engineering and Assistive Technology Society of
North America (RESNA). As a provider of adaptive sports equipment, we ask that you abide by
the RESNA Adaptive Sports Equipment standard for responsible use:
Your Responsibility Code:
1.) Always stay in control –Be able to stop or avoid other people or objects.
2.) People ahead have the right of way. It is your responsibility to avoid them.
3.) You shall not stop where you obstruct a trail or are not visible from above.
4.) Whenever starting downhill or merging into a trail, look uphill and yield to others.
5.) Always use devices to help prevent runaway equipment (e.g., SMBs
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6.) Observe all posted signs and warnings. Keep off of closed trails and out of closed areas.
7.) Prior to using any lift, you shall have the knowledge and ability with or without personal
assistance to load and unload safely.
The monoski, also known as a sit-ski, is intended to be used by people with limited use (or
absence) of the lower extremities. The recommended maximum weight of the skier is 230 Lbs.
(105 kg).
Your monoski is already assembled when delivered unless otherwise requested. Please see the
picture below to familiarize yourself with all components and parts. The frame and suspension
arm of the Hydra are made of 7075 aluminum. The coil-over shock absorber is a product of
Penske Racing Shocks custom built for DynAccess monoskis (see Shock Manual for details).
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SMB stands for sit-skis, mono-skis and bi-skis
General Description

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Various seat buckets can be mounted on the Hydra, including DynAccess' thermoformed bucket
seat complete with seat belts and bucket straps. A photo below is that of Aspen Seating/Ride
Design’s bucket.
A. Lap Belt
B. Bucket Seat
C. Ratcheting thigh belt
D. Frame
E. Footrest
F. Foot strap
G. Shock absorber
H. Remote reservoir
I. Foot tower
J. Sole
K. Chest belt
L. Back handle
M. Evacuation straps
N. Side handle

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Mounting the Seat:
A seat of your choice may already be mounted on the monoski when delivered. If you should
change to a different seat for the monoski, please contact DynAccess regarding its compatibility
with the Hydra.
If you need to mount a seat, place the seat bucket onto the frame. Four ¼” bolts and four
nylock locking nuts are used. The two bolts in the front are 1.25” long and the two in the rear
are 1.0” long. Large and relatively thick washers are used inside the bucket seat.
Plenty of anti-seize (preferably food grade) should be used on the four seat mounting bolts,
since stainless steel fasteners in general are prone to seizing. Food grade anti-seize has already
been applied on the fasteners. If the plan is to seldom remove the seat then thread locking
compound may be used on these bolts as well; clean the bolts and nuts carefully before using
thread locking compound.
Torque the bolts properly and be careful not to seize the fasteners. Replace any worn, over-
torqued, seized or otherwise damaged fasteners.
In general, bolts and nuts have three different means of preventing getting loose:
Nylon insert locking nuts (“nylocks”) should be discarded after each use. All-metal deformed-
thread locknuts, as well as the bolts used with them, should be discarded after each use. With
thread locking compound such as “Loctite”, nuts and bolts can be reused with new thread
locking compound applied.
Caution!
Please be advised that some non-DynAccess Seats are not optimal for the Hydra and mounting
such a seat on the Hydra may result in serious injury or death.
Mounting bindings and optional binding blocking set:
The DynAccess Hydra can be fitted to the snow ski using conventional high-strength bindings.
The standard length of a DynAccess foot is 325 mm.
Instructions

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DynAccess offers a “blocking set” designed to fit the following bindings: Marker Comp 20 or 30
bindings, Marker Race Xcell/Xcomp 24, Head Freeflex Evo 20 X RD /Fischer RC 4 Z 20X Race
Freeflex Bindings, and Atomic EGA X20 bindings. The blocking set consists of a front blocking
plate and a rear block with a locking pin.
According to the RESNA standard, ski bindings for monoskis are not intended to release. The
front plate prevents the toe binding from releasing under most circumstances. It is made of a
super-austenitic stainless steel with superior corrosion resistance, high strength and ductility. It
mounts under the binding. Professional mounting using longer bolts is recommended.
The rear block is CNC milled and made from material with high low-temperature ductility.
Installing the binding on the Snow-Ski and the monoski
The DynAccess monoski can be fitted to the snow ski using conventional high-strength bindings.
The Hydra works best with the binding mounted at the boot center of your ski. The standard
length of a DynAccess foot piece is 325 mm, but other
lengths (e.g. 300 mm) are also available upon request.
To fit the monoski onto your ski:
1. Make sure you completely understand your
particular bindings and how they are adjusted.
2. Remove any snow or ice from your monoski’s
foot and the ski’s bindings.
3. Secure the ski so that it does not slide, then
raise the monoski to about a 30 degree angle
and fit the tip of the foot into the front binding
(see image).
4. Center the monoski over the ski and binding, keeping the tip of the foot in the front
binding, and push down until the rear binding locks.

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5. Check to ensure that the foot has locked properly into the bindings.
6. Many programs and skiers pin the front binding and block the rear binding such that
they cannot release.
Adjusting the Center of Gravity (COG):
The standard setting of the Hydra is in the center, from which the skier can move 3" (75mm)
forward or 3" (75mm) back in 1" (25mm) increments. The Hydra was designed such that if the
bindings are mounted boot center for a 325 mm boot, then for ~95% of all monoskiers the
center location will be optimal. Mounting the bindings boot center is important for the ski to
bend correctly in turns.
There are a few exceptions to the COG mounting:
- skiers with one or two legs missing may want to move forward. 1" or 2" (25 mm or 50 mm) is
usually sufficient,
- skiers with heavy legs and/or heavy feet may want to move back. 1" (25 mm) is usually
sufficient. Moving further back is usually not a good idea,
- racers who want a lot of early tip pressure may want to move forward on the ski,
- skier who ski very steep terrain may want to move back on the ski. However, this tends to
make the ski less harmonic in anything but very steep terrain,
- some park skiers also like to move back on the ski as this tends to reduce the risk of breaking
skis.
Caution!
The Hydra balances differently than other monoskis because of different kinematics (the
frame moves backwards when loaded whereas most other monoskis move forwards
when loaded). The Hydra will therefore sit considerably further forward on the ski when
unloaded than other monoski. Dowel tests can be misleading and are in general not
recommended.

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To change the center of gravity:
1. Lay the monoski on its side.
2. Locate the two bolts connecting the foot tower to the foot.
3. Remove the two bolts, and put them and the six washer in a safe place. You may need
to loosen the bolts just above the removed bolts to release the pressure.
4. Slide the frame forward or backward to adjust your center of gravity and center it with
the proper holes. Align the holes perfectly, using for example a drift (tapered alignment)
pin.
5. Replace the bolts, washers and nuts
6. Take care to ensure that all screws are tightened properly. Do not over-torque the bolts.
Caution!
Make sure to install all parts, in particular the washers, correctly. The thick conical washers are
very important; do not replace them with flat washers as this may damage the rodends and
lead to failure.
Sitting in the Seat:
When sitting in the bucket seat, sit deeply so that it is snug throughout your entire hips and
bottom. You may want to lean forward and wiggle down into the seat, adjusting so that your
pelvis is as far into the rear of the seat as possible.
Once you are seated properly adjust the height of the footrest. You may want your thighs to
contact the seat edge slightly, but not so hard that you could not slide a finger under your
thighs.

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Adjusting the Footrest:
You can adjust the height of the monoski’s footrest. To do this:
1. Locate the two long ¼” bolts attaching the footrest to the
frame.
2. Remove the bolts, nuts and spacers. Put them in a safe
place. Note that there are O-rings in the spacers.
3. Move the footrest up or down as desired and center it
with the proper holes.
4. Replace the two screws and four spacers to reconnect the
footrest to the frame. O-rings should be against the frames.
Take care to ensure that all screws are properly torqued.
Buckling your belts:
Your monoski comes standard with four strap belts and one ratcheting belt. The buckles for the
strap belts are of the non-sewn type that are easy to adjust. Straps are secured with a tri-glide
on one side to prevent the straps from slipping out of the buckle.
Caution!