White brothers cycling WBUD150 User Manual

OWNERS MANUAL FOR

WHITE BROTHERS UD-150

DOWNHILL

WHITE BROTHERS CYCLING
A DIVISION OF EKO SPORT, INC.

580 NORTH WESTGATE DR.

GRAND JUNCTION, CO 81505

WWW.WHITEBROTHERSCYCLING.COM

Owners Name: ___________________________________________________________________________
Address: _________________________________________________________________________________
_________________________________________________________________________________
Phone: ___________________________________________________________________________________
Purchase Date: ___________________________________________________________________________
Purchase Location: _______________________________________________________________________
Serial # __________________________________________________________________________________
(Located on the backside of the right axle clamp)

SAFETY

1.) NEVER REMOVE STEER TUBE FROM CROWN. THIS
IS A PRESSED IN PART, REMOVING IT WILL RENDER
BOTH CROWN AND STEERER INOPERABLE*. MAKE
SURE YOUR FORK CAPS AND ALL FORK HARDWARE
(brake studs, pinch bolts, etc.) ARE TIGHT.

2.) DO NOT PERFORM ANY MODIFICATIONS OR
ADJUSTMENTS THAT ARE NOT OUTLINED IN THIS
MANUAL. SEE THE TUNING SECTION OF THE MANUAL
FOR MORE DETAILS.

3.) INSPECT YOUR FORK BEFORE EVERY RIDE.
INSPECT THE CROWN, TUBES AND AXLE SEAT AREAS
FOR ANY SIGNS OF FATIGUE, BENDING, CRACKING OR
OTHER DAMAGE. IF YOU NOTICE ANY TYPE OF
DAMAGE, DO NOT RIDE ON YOUR FORK.. RETURN IT
TO YOUR DEALER FOR A COMPLETE INSPECTION AND
NECESSARY REPAIR OR WARRANTY STEPS. PLEASE
REFER TO THE WARRANTY SECTION OF THIS
MANUAL.

4.) PERFORM ALL RECOMMENDED MAINTENANCE
ACCORDING TO THE MAINTENANCE SECTION OF
THIS MANUAL. FAILURE TO PERFORM
MAINTENANCE COULD DRASTICALLY REDUCE
YOUR FORK’S LIFE AND PERFORMANCE.

5.) WHITE BROTHERS RECOMMENDS THAT YOU
WEAR PROPER SAFETY EQUIPMENT EVERY TIME YOU
RIDE, INCLUDING AN APPROVED BICYCLE HELMET.
NEVER RIDE A T NIGHT WITHOUT LIGHTS!

* IF SERVICE BECOMES NECESSARY OR REMOVAL
OCCURS, PLEASE CALL WHITE BROTHERS
CUSTOMER SERVICE FOR PRODUCT EVALUATION
AND DIAGNOSIS.

APPLICAT IONS

Thanks for purchasing your new White Brothers Pro Forx. You
are in for the best ride of your life. Our forks are designed to give
you the level of performance you need to ride at your absolute
peak.

The White Brothers Pro Forx UD150 features a lightweight coil
spring and a sealed, externally adjustable cartridge damper. This
technology is borrowed from motorcycling and offers the best
possible suspension action. Steering accuracy is improved over
conventional MTB forks by utilizing dual billet aluminum
steering crowns, oversized 31.75mm fork tubes, inverted
stanchion/slider design and large 20mm axle. Fork travel has
been set at 6” to offer the best performance for downhill racing
terrain. High-cushion bottom bumpers are used to minimize
hard bottoming.

Every possible effort has been made to make the White Brothers
Pro Forx very light in weight and perform at a level superior to
other forks on the market. To insure peak performance, proper
installation and periodic maintenance is required. Please read
this manual in its entirety to familiarize yourself with the fork and
insure your satisfaction with this product.

White Brothers Pro Forx are designed for off-road use only.
They are not equipped with proper reflectors for on-road use. If
you are going to use your forks for road use, have your dealer or
mechanic install reflectors that meet the Consumer Product
Safety Commission’s (C.P.S.C.) requirements for bicycle
standards. If you have any questions concerning C.P.S.C.
Standards, please talk to your dealer.

When using your forks on public land and trails, please respect
the rights of other users and stay on established paths and trails.
By mounting biking responsibly, you help to insure the future of
our sport.

Copyright 2001, Eko Sport, Inc. All Rights Reserved.

FORK INSTALLATION

TUNING

White Brothers Pro Forx UD150 feature a 1 1/8” threadless steerer tube.
If you have a threaded type fork on your bicycle, consult your dealer for
the appropriate upgrade parts necessary to convert to a 1 1/8” threadless
steerer tube.

NOTE: Some frames are not adequately reinforced to handle loads
applied by stiffer dual crown forks. Check with your frame manufacturer
to verify dual crown fork compatibility

1.) Remove old forks from the bicycle. See your bicycle’s owners
manual. Measure the diameter and length of your old forks steerer tube
to insure that the White Brothers Pro Forx steerer tube is the correct
diameter and has sufficient length for the installation.

2.) Remove the crown race from your old forks. Note: Replace the
bearings if there are any signs of wear or corrosion

3.) Press the crown race onto the steerer of your White Brothers Pro Forx
(figure 1).

4.) Preassemble headset by: Sliding fork steerer tube through headset
bearings. Then install top headset, top crown, stem spacer (optional),
and steering stem onto fork steerer tube. Refer to headset owners
manual if you have any questions about this preassembly.

5.) Mark steerer tube at top of steerer stem. Steerer must then be cut
3mm (1/8”) below this mark. Consult a dealer or mechanic if you do not
have the proper tools for cutting the steerer tube.

6.) The special star fangled nut must now be installed into the steerer.
We recommend dealer installation of this nut since a special tool is
required.

7.) Clean and grease all headset bearings and races to prepare them for
assembly.

8.) Now assemble headset as done in Step 4 (figure 2).

9.) Install the top steering crown. Install the steering stem (threadless
type is required) and handlebars. Set your bars to your desire height.

10.) Install the threadless mounting cap. Tighten the top threadless stem
bolt until there is no play in the fork tube. The forks should rotate freely in
the head tube. Secure the pinch bolts on the steering stem. Consult the
installation instructions for your threadless bearing set to insure correct
installation and tension of the headset.

11.) TIRE CLEARANCE: The fork tubes can be adjusted up or down in
the fork crowns to adjust ride height and steering geometry. NOTE: At
full extension of the fork, a minimum of 6” (152mm) clearance must exist
between the tire and the bottom of the steering crown. DANGER: Any
less clearance than this will allow the tire to contact the bottom of the
crown when the forks are fully compressed. Next check to make sure the
top of the fork tubes fit all the way through the top steering crown. If
insufficient clearance exists, you must switch to a smaller diameter front
tire.

12.) Install your front brakes and adjust following the manufacturers
specifications. See additional instructions below. NOTE: Only disc type
brakes can be used with the White Brothers Pro Forx UD150.

13.) WHEEL/BRAKE INSTALLATION: The White Brothers Pro Forx
UD150’s are designed for a downhill type hub utilizing a 20mm axle.
Install front wheel with disc rotor next to left side of fork. Slide axle all the
way through. Make sure disc rotor doesn’t contact left fork axle seat
when axle is tightened fully. If it does, a custom spacer will have to be
fabricated to space hub/rotor away at least 3mm from left fork axle seat.
At this time the brake caliper should be mounted and alignment checked
with the disc rotor. Follow the disc brake manufacturers installation
instructions to insure correct brake rotor brake caliper alignment

14.) RIM CENTERING: See your dealer or professional wheel builder to
have the rim of your choice laced to your downhill hub. The wheel builder
will need to lace the rim so that it is directly centered between the fork
legs.

15.) FINAL WHEEL INSTALLATION: Lightly grease front axle and install
front wheel to forks. Tighten axle completely. Now tighten both left and
right fork axle seat pinch bolts. Follow the disc brake manufacturers
installation instructions and recommended torque for mounting brake
caliper to left fork leg.

16.) Route hydraulic brake cable up to the brake lever. Make sure that
the cable is routed so that it cannot foul on tire, fork crowns, or steering
stops through full up and down fork travel and side to side steering radius.

17.) Check to see that your brakes are adjusted and working.

18.) STEERING CLEARANCE: Due to the White Brothers Pro Forx
double crown design, the fork tubes or fork steering crowns will contact
the bicycle frame at full steering lock to the left and right. To eliminate the
chance of damage to the fork or frame, a cushion stop must be fabricated
to eliminate metal to metal contact. For bumpers, elastomers or thick
pieces of rubber will work fine. Secure cushion stop to the frame or fork

To get the most from your White Brothers Pro Forx it is important that you
tune the forks to fit your style of riding and the conditions in which you ride .
Initial break-in period. Your new fork is designed to break-in over a
period of 10 hours or more of riding. As all of the parts bed into each other,
the stiction (friction) of the forks will reduce and the forks will absorb the
bumps better. After this initial break-in, fine tuning the spring preload and
cartridge damper may be beneficial to achieve the best possible fork
performance for your weight and riding style.

Tuning Your Springs

There are two ways to adjust your forks. The first is by changing the
spring pre-load or changing the spring for a completely different rate. The
spring basically controls the quality of the ride. Stiff springs handle major
obstacles and drops better, but don’t give as smooth of ride over braking
bumps and other small obstacles. Your White Brothers Pro Forx comes
with a standard rate spring installed, with the preload adjusted to zero.
Note: Zero spring preload means the preloader is just touching the spring,
and the spring is under no tension (at full fork extension). For the majority
of riders, this should give a compliant ride, yet remain resistant to
bottoming. Pre-load should be set, then left alone. If you feel your forks
are bottoming too easily, then switch to the heavier spring supplied with
your forks. Your pre-load should be set with 1/4” to 1/8” of free sag. This
means that with no load on the bike, the forks should come within 1/4” to
1/8” of returning to full extension after compressed. If forks are too stiff or
too soft with either of the springs supplied, WB offers an optional Soft and
X-Heavy Fork Spring (see Spring Rate Chart on page 12). Contact your
WB dealer to order these.

Tuning Your Cartridge

Because of your forks coil spring, you will notice the forks have far better
action than other mountain bike forks you might have used. Adjusting the
cartridge should only be done after you are completely happy with your
spring choice, and the proper sag has been set. Your White Brothers Pro
Forx UD150 comes with the cartridge adjusted in the middle of its’ range.
The standard setting is 8 clicks out from all the way in (clockwise). Use the
following guide lines to determine if further adjustment is needed.

A) If your forks rebound too slowly, turn the adjustment knob on the top of
the right fork leg all the way counter-clockwise (10 turns out is the
maximum). The forks should absorb and return fast enough to absorb the
next major obstacle. A sign that your forks are rebounding too slowly is if
they feel like they pack-up or continue to compress as you go through
rough sections.

B) If your forks are rebounding too fast, turn the adjustment knob on the
top of the right fork leg clockwise two clicks at a time. A sign of too fast of
rebound is if the forks deflect and the bicycle is hard to hold in lines. The
front wheel will also bounce and appear “busy” ie. You get an additional
bounce after landing from a drop.
NOTE: The damper adjuster also has some affect on compression
damping. As you turn in (clockwise) the damper adjuster, both the
compression and rebound damping will become slower. If a stiffer spring
is installed, your standard setting should be two positions stiffer
(clockwise). A light rider that has installed a softer spring will usually be
most satisfied with the damping set at the lightest position (10 turns out).

Trouble Shooting

Maintenance

Problem: The fork has “striction” (moves up and

down in jerky movements). See
Tuning section for break-in notes

Cause: This is normally caused by lack of

lubrication or dirt in the seals and/or
bearings, or forks are not sufficiently
broken in

Solution: Clean and lubricate the fork as

described in the maintenance section

Problem: The fork does not return to it’s full

extension

Cause: This is normally caused by a lack of

spring preload

Solution: Increase the spring preload

Problem: The fork returns to it’s full height too

aggressively, feels like an air fork or

“tops out”
Cause: Too much spring preload
Solution: Reduce the spring preload

Problem: The fork bottoms too easily
Cause: Incorrect spring choice
Solution: Install stiffer option spring and re-

adjust damper setting

Problem: The fork doesn’t use it’s full travel
Cause: Incorrect spring choice
Solution: Install softer option spring and re-

adjust damper setting

Your White Brothers Pro Forx requires periodic maintenance to insure
peak performance and long life. Moisture and contamination may build
up inside the fork. We suggest you disassemble your forks, inspect, clean
and re-grease them after 30 hours of use. If the forks appear to be
relatively clean, you can probably go 40 hours between servicing. If the
forks appear dirty, you should service them every 20 hours. The three
things that will most effect the service interval and performance of your
forks is water, mud and dust. Depending on how much time you use your
forks in those conditions will determine how much service they require.
NOTE: When cleaning the fork, it is not recommended to direct water
spray at the seals.
NOTE: Neglecting proper fork maintenance will reduce the forks life.
Internal build up of water and dirt, or a lack of lubrication will cause
excessive wear to the forks.
Basic service should include disassembly the forks, cleaning and re­greasing all shafts and seals. At this time, the forks should be carefully
inspected for wear and damage before reassembly. Disassembly of the
damper cartridge should be left for a dealer who is familiar with servicing
the WB Pro Forx cartridge damper.

Basic Fork Disassembly

1) Disconnect from brake caliper.
Remove wheel assembly by loosening
fork axle seat pinch bolts loosening and
removing front axle.

2) Loosen pinch bolts in steering crowns
and slide each fork leg down and out of
steering crowns. If cap gets stuck out of
top clamp, use a flat screw driver to
create separation.

3) Beginning with the right fork leg
assembly, turn damp adjuster knob to
farthest out position (counterclockwise)
than loosen small 1.5mm allen set screw
in cap and remove adjuster knob by
pulling upward. NOTE: Measure height
of brass adjuster protruding from the top
of it to the face of the fork cap. (should be
about 4.7 mm) This dimension is crucial
at reassembly to maintain the forks
adjustment range.(see step 15 of
reassembly)

Figure 2

Figure 1

Problem: The fork bounces up and down rapidly
Cause: Insufficient rebound damping
Solution: Increase damping by adjusting

clockwise (2) clicks at a time

Problem: The fork has heavy feel, doesn’t return

quick enough for consecutive bumps
Cause: Too much rebound damping
Solution: Decrease damping by adjusting

counterclockwise (2) clicks at a time

4) Unthread top fork cap
(counterclockwise) utilizing a WB
spanner tool part no.97-714. If fork
stanchion is clamped in vise during this
procedure use jaw pads to prevent
damage to fork. Also avoid excessive
clamping force to avoid crushing fork
stanchion (figure 1).

5) Once top fork cap is loosened
sufficiently that it is no longer attached to
fork stanchion, grasp lower fork leg at
axle seat and compress fork
approximately 3”. Loosen 14mm nut on
cartridge shaft while holding top cap from
rotating with the WB spanner tool (figure

2). NOTE: Carefully remove top cap from
cartridge rod while holding over a box or
bin. A small ball bearing will fall out and it
is ver y easy to lose.(figure 2a).

6) Remove nut from cartridge shaft, nylon
bottom out spacer and coned bottom out
bumper. Lower fork leg can now be
removed from right fork stanchion by
sliding downward (figure 3). No further
disassembly of right fork leg is necessary
unless cartridge damper service is
required. If so, use adjustable wrench
and grip large flats on cartridge damper
and unthread counterclockwise from
lower fork leg(figure 3a). NOTE: Do not

Figure 2a

Figure 3

Figure 3a

remove brass damping adjust needle
from cartridge. Oil can be lost from
cartridge if this needle is removed.
Place all parts to the side carefully
noting order of which they are
assembled. Remove fork seal and foam
wiper from fork stanchion.

7) Unthread top fork cap
(counterclockwise) on left fork utilizing a

Figure 3a

WB spanner tool part no. 97-714. If fork
stanchion is clamped in vise during this
procedure use jaw pads to prevent damage to fork. Also avoid excessive
clamping force to avoid crushing fork stanchion .

8) Once top fork cap is loosened sufficiently that it is no longer attached to
fork stanchion, grasp lower fork leg at axle seat and compress fork
approximately 3”. Spring spacer must be pulled downward to compress
spring to access the 9/16mm hex nut on neutral shaft. Loosen 9/16mm
nut on neutral shaft while holding top cap from rotating with the WB
spanner tool (figure 4). Remove fork cap.

9) Remove nut from neutral shaft, spring spacer, nylon bottom out spacer
and coned bottom out bumper. Hold neutral shaft so that it doesn’t fall
inside of fork. Next remove spring, spring seat guide, and spring preload
spacer (if any). At this time install the 9/16” nut on the neutral shaft to
keep it from falling inside of lower fork leg. Lower fork leg can now be
removed from left fork stanchion by sliding downward (figure 3). No
further disassembly of left fork leg is necessary unless neutral shaft fell
down inside of lower fork leg. If so use small adjustable spanner tool to
unthread neutral shaft nylon guide bearing counterclockwise. At this time
neutral shaft with top out bumper can be removed. Place all parts to the
side carefully noting order of which they are assembled. Remove fork
seal and foam wiper from fork stanchion.

bottom of threads. Before the cap is placed on, be sure brass adjuster is
fully tightened into shaft of damper. Make(figure 15a) sure detent spring
and ball bearing are positioned correctly in fork cap. With fork on its side
carefully assemble fork cap over damp adjust needle head making sure
ball bearing detent stays in position. Now screw cap clockwise until brass
adjuster protrudes from cap face approximentely 4.7mm (as measured in
step 3 of basic fork dissassembely). Now maintain position of cap with
spanner tool, and tighten hex nut up to the underside of cap to secure its
position.Then place adjustment nob on cap so it rests flush to the caps
surface, and tighten the 1.5mm screw. Now check to see if 10 clicks
counter clockwise can be made. If not consult a WB Dealer; if yes, fully
extend fork and tighten cap into fork stanchion with spanner tool. Next,
tighten 14mm nut up against fork cap. Finally, fully extend fork and fully
tighten fork cap into fork stanchion using the WB spanner tool.

15) Reassemble fork legs in steering crowns and tighten into original
position. Install front wheel and brakes and detailed in Fork Installation
instructions (pgs. 2-3).

10) At this point clean all parts with a clean, non-abrasive rag. A mild
grease cutting cleaner or solvent might make this an easier task.
Once cleaner, inspect seals for tears or cracks. If okay, regrease them
with White Brothers Suspension Lube or other suitable, non-lithium
grease. If your seals are no longer serviceable, check the General
Disassembly Parts Table section of this manual for the proper
replacement part numbers. Your dealer will be able to order any
replacement parts you might need.

11) Next, inspect the fork tubes for wear, nicks or scrapes. If there is
noticeable play between fork legs and fork tubes, the DU bushes located
inside the upper fork stanchion may require replacement. Consult your
dealer for service options. Finally inspect the cartridge damper for any
signs of leakage or scratches and wear on the protruding cartridge shaft.
The cartridge damper is a sealed unit that is threaded into the right fork. It
requires only occasional maintenance (oil and seal change every 80 to
120 hours of use). Consult White Brothers or your dealer if servicing or
repair is necessary.

12) If everything is free of problems, coat all parts with a light coating of
White Brothers Suspension Lube or other suitable, non-lithium grease.
Also lube the DU bushings that are located inside fork stanchions by
dipping a socket extension in grease and applying the grease into the
inside of the fork stanchion on the DU bushings.

13) Slide fork seals and foam wipers over both fork lower legs. Seals
should be greased and wipers should be oiled prior to assembly. Slide
both fork stanchions over fork lower legs and fully compress. Make sure
that both the neutral shaft (w/nut installed to keep it from falling inside of
lower fork leg) and cartridge damper are installed in lower fork legs prior to
assembly.

14) Assembly (Left Fork Leg): Remove 14mm nut while holding neutral
shaft up. Install preload spacer, spring seat guide, bottom out bumper
(tapered end facing down), spring, nylon bottom out spacer, 14mm nut,
clear spring spacer, and top cap. Pull down on clear spring spacer to
compress spring sufficiently to allow 9mm spanner to hold flats on neutral
shaft and full tighten fork cap with WB spanner tool. Next, tighten 14mm
nut against fork cap. NOTE: Spring preload can be increased or
decreased by adding or removing thin nylon preload spacers under
spring seat guide. Less preload will offer a softer initial ride and lower ride
height. More preload will offer a stiffer initial ride and higher ride height.
Finally, fully extend fork and fully tighten fork cap into fork stanchion using
the WB spanner tool.

14) Assembly (Right Fork Leg): Install bottom out bumper (tapered end
facing down), nylon bottom out spacer and 9/16” hex nut positioned to

Your White Brothers Pro Forx have the
standard rate (charcoal) springs already
installed. Also included in this box is a pair of
heavy rate (brown) springs. If you wish to
change the spring rate of your forks, please
consult an authorized dealer.

MAINTENANCE

DATE SERVICE PERFORMED DATE SERVICE PERFORMED

WARRANTY

White Brothers forks are designed to enhance riding pleasure and as such are warranted to be free from defects in materials and workmanship
for a period of one year from the date of purchase. On receipt of the fork by White Brothers, if they are found to be defective, White Brothers will
determine whether to replace or repair the fork. This warranty is the sole and exclusive remedy. White Brothers shall not be liable for any indirect,
special or consequential damages. Warranty does not apply to any product that has been installed improperly or adjusted using methods not
outlined in this manual. Warranty also does not cover forks that have been misused, or forks that are missing or have altered serial numbers
(located on the backside of the right fork stanchion). The forks are not warranted against damage in the appearance of the fork or for
modifications not outlined in this manual. This warranty does not cover breakage, bending, or damage that may result from crashes, falls or
abuse. Normal wear (i.e. seals, bushings, slider finish, etc.) and wear and damage caused by lack of proper maintenance is not included. *A
copy of your proof of purchase, including your name, address, phone number and fork serial number (located on lower left leg) must be
returned within 30 days of purchase to activate and validate this warranty. Customers in the USA please contact your dealer for a Return
Authorization Number (RA#) before returning the forks. All forks returned for inspection must be sent freight paid to:

C/O White Brothers Customer Service

Www.whitebrotherscycling.com

*Customers outside the USA please contact the dealer or distributor in your area

Eko Sport, Inc.

580 North Westgate Dr.

Grand Junction, CO 81505

Phone [phone]

Fax [phone]