06 YZ250 manual Question

airmanloco

Member
Oct 2, 2006
12
0
Hey guys, could someone tell me if proceedure for disassembling forks and reassemble (specifically proper bleeding of damper on reassembly) is in the owners manual or is it in the service manual. My CRF actually had it in the owners manual so just thought I check before I throw down the $60 for the service manual. Might have to do that anyway since the search I just did returned no results for any place I could even buy an owners manual. Of course if someone wants to just tell me that would be fine too. ;) The procedure for the Showas on my CRF was to pump the damper rod a few times and then extend it only 10 inches or something and check the oil heighth. I know the Kayabas are very similiar.
 

kingbrian

Member
Jul 20, 2006
123
0
60 bucks fer a service manual??? better be gold plated fer that price.. i got mine fer 18.99 at my local dealer, and seen um even cheaper at that auction site. but id go with that for wut you need.
 

psalm3124

Member
Apr 21, 2005
101
0
The manual that came with my 06YZ250 has the instructions on how to service the forks. I assume this was the owner's manual as I did not buy the service manual. I know I just did it.
 

Rcannon

~SPONSOR~
Nov 17, 2001
1,886
0
I copied this some time ago from this site. It was from an article eric published. I believe the directions were for the 05 forks, but it worked very well on my 06.

You can also download a copy of the owners manual at http://www.yamaha-motor.com.au/

Between the two you'll be able to handle things.


Disassembling the Forks
Use a Race Tech 8-point 50-millimeter box wrench to remove the outer fork
cap.

Depress the slider tube and drain the oil from the outer chamber. Capture
the oil and recycle it at an automotive garage or oil express.

Unthread the rebound adjuster bolt with a 17-millimeter socket while holding
the axle clamp in a vise. The rebound adjuster bolt will separate from the
fork tube, but it still needs to be unthreaded from the cylinder rod.

Extend the cylinder rod by pushing on the top of the cartridge to expose the
damper rod jam nut. Place a Race Tech flat-wrench on the cylinder rod and
loosen the jam nut and the rebound adjuster bolt.
Remove the cartridge assembly and the spring from the top of the fork leg.

Clamp the upper part of cylinder in a shaft-block and vise, then use a
hexagonal socket slug to remove the compression valve assembly. Pull to
separate the compression valve from the cartridge cylinder.

Disassemble the cartridge for cleaning. Start by clamping the cylinder rod
in a shaft-block and unthread the jam nut. Now slide the cylinder rod out of
the top of the cylinder.

The best method for cleaning the oily components of the fork is a high flash
point (120F) mineral spirits solvent. Solvent breaks up the mixture of
grease, oil, and metal debris that contaminate the forks. Commercially
available products include PB Blaster available from most auto parts stores.
Non-chlorinated brake cleaner is the best choice for final cleaning. Allow
the parts to drip dry.

Changing Seals, Wipers, and Bushings
The fork tube and slider must be separated to change the seals and bushings.
Use a small straight-blade screwdriver to pry off the wiper; now remove the
circlip and slide the parts down the tube.

Heat the lower part of the fork slider with a propane torch to expand the
fork slider away from the outer bushing; this will make it easier to
separate the tube and fork slider. This will also prevent the outer bushing
from being pushed over the inner bushing, which will avoid scrubbing off the
Teflon coating. Grasp the fork tubes with your hands and quickly extend them
several times until the tubes separate.

The bushings, seals, circlip, and wiper will be retained on the inner fork
tube.
Remove the fork tube bushing by spreading it with a screwdriver and
slide it off the end of the tube. Discard the old oil and dust seals and
inspect the bushings for wear.

Put a dab of grease under the lip of the oil seal and dust wiper.
Install a new wiper and bushing on the fork tube. Before installing the
seal, slide a seal-bullet over the end of the fork tube to prevent damage to
the new seal. Make sure to install seals, bushings, aluminum spacer and
circlip in exact order.

Use a seal driver on the aluminum spacer to seat the outer bushing in the
fork slider, and then use the driver on the seal. Install the circlip and
use a plastic mallet to tap the wiper evenly into the slider.

Set the fork tubes aside and get ready to assemble the inner cartridge.

Assembling the Cartridge
Insert the piston rod assembly into the cylinder using a 12-millimeter
T-handle to manipulate the piston rod into place.
When installing the jam nut on the end of the piston rod, ensure that the
jam nut is threaded all the way up on the piston rod.

Clamp the cylinder in the shaft-block and tighten the vise so you can hold
the cartridge upright for oil filling. Overfill the cartridge to an oil
height of 130-millimeters from the top edge of the cylinder with Yamaha
Suspension Oil 01. You'll need a total of two cans to refurbish both fork
tubes.

Perform non-pressurized bleeding of the cartridge by moving the rod a total
of one inch up and down to help displace trapped air to the top of the
cylinder. Stroke the rod about thirty times to bleed the cartridge, and then
wait ten minutes for the air to bubble upwards.

Wipe a dab of grease on the o-rings prior to inserting it into the top of
the cartridge. Tighten the fork cap to factory specs.

Perform pressurized bleeding by stroking the cartridge no more than two
inches for a total of thirty times. This will compress the remaining air
bubbles and position them near the top for final bleeding.

Clamp the bottom of the cartridge in the vise and set at about a
15-degree angle so the air travels up to the top. Position the holes of the
cartridge at 6 and 12 0'clock so the air purges out the top hole and the
excess oil purges out the bottom. Compress the cartridge slowly through its
full travel.
You should hear air bubbles trickle out of the top hole while oil drips out
the bottom hole. This procedure will dramatically improve the consistency of
the fork action.

Clamp the axle mount into the vise and slide the white plastic tube spacer
and the spring into the tube with the metal ring of the spacer facing the
spring.
Install the metal spring spacer on to the cartridge with the ring facing the
spring.

Insert the cartridge into the tube and compress the cartridge until the rod
extends far enough to install the flat wrench. Install the long aluminum
rebound adjuster rod into the piston rod then thread on the rebound adjuster
until it bottoms out on the rod not the jam nut. There is the danger that
the forks will be unequal lengths if you get this procedure wrong.
Tighten the jam nut against the rebound adjuster by holding a wrench on the
jam nut and a socket on the bolt. Take care when removing the flat-wrench
because the spring pressure will cause the rebound adjuster to slam into
place. Put a dab of grease on the threads of the rebound adjuster and
tighten it into the fork tube to factory torque specs.

The next step is to fill the outer fork tubes with a measured volume of oil.
The oil volume and height generates the air spring's progression. The lower
the oil volume the less progressive the effects of the air spring. The
higher the volume the more progressive your air spring will be. Consult your
owner's manual for suggestions on oil volume for your riding demands. There
are no bleeding considerations for the outer fork tubes.

The last step is to tighten the fork cap hand-tight because the triple clamp
provides the extra torque to prevent the cap from unthreading.
 

CRazy250

Member
May 28, 2006
334
1
yeah new manuals are expensive, its like they want you not to buy it and just to bring your bike for them to work on, i payed close to 50 for my factory yamaha manual for my 2002 yz125 last spring
 
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