You should read these before starting.
Firstly, this is a guide. I accept no responsibility for any mistakes or omissions. If you break it or injure yourself then thats your problem.
If you're using this guide to change fork oil, only follow the drain, clean and refill parts of the process.
Tools needed:
Special tools:
Parts:
You may need new dust seals (depending on the condition of the old one - if they are ok they can be reused).
You may also need new seal retaining clips if the old ones are corroded - these are not expensive so it may be a good idea to replace them regardless.
Bushes if you intend to replace these as well.
Right. The job.
Although it is possible with the front fairing & headlamp assembly in place it is easier to remove it first.
After removing the fairing etc, remove the front wheel.
(It's probably worth having a read of these notes before you do so, but if you don't, then be sure to take care not
to damage the speedo sender unit (1) or loose the inner rotor part).
Tie the front calipers (2) to the handlebars so that the brake pipes are not under stress or damaged (2).
Work on one fork at a time, do not mix components between forks.
Loosen the top clamp bolt on the fork you are working on (1). When this is loose also loosen, but do not
remove, the cap bolt on the fork (2)
(Note: The bike shown is a MK2 fazer, the MK1 does not have the preload adjuster)
A couple of turns is enough.
Next loosen the lower clamp bolt. In the image below the hex clamp bolt has been completely removed, you only
need to loosen it (we removed it for another reason not connected with the fork seals*)
When this bolt is released the fork will slide down so be prepared to catch it.
(*If you're wondering, the owner of this bike sheared the other clamp bolt so we removed this one to measure it )
Catching the fork leg
Try to loosen the damper retaining bolt located in the bottom of the fork.
Sometimes you will be lucky, sometimes you won't. Often it won't loosen because the damper assembly inside the
fork is turning. If it won't loosen, just ignore it and carry on - you can remove it later.
Next the cap bolt can be completely undone. IT IS UNDER SPRING LOADING SO WILL SHOOT OFF IF
YOU ARE NOT CAREFUL!
You will need to keep hold of the top fork tube as when the spring tension is released it will try to slide down
into the fork lower - we are not ready for this yet.
Tip out the old fork oil and be prepared to catch (in this order), a solid washer spacer, a hollow tube spacer, a
normal washer spacer and finally the spring.
Note which way the spring comes out - the closer coils are at the top of the fork.
Here is everything you should have:
1 Cap bolt (MK1)/preload tensioner(MK2)
2 Solid washer spacer
3 Hollow tube spacer
4 Normal washer spacer
5 Spring
Wipe them off and put them out of the way.
Holding the fork upside down, pump it a few times to remove the last of the oil.
** DO NOT LET THE FORK BOTTOM OUT OR IT WILL JAM! **
If it does jam then you may be able to release it by pulling it hard, however since you and the fork are probably
both covered in oil this isn't easy. If you cannot release the fork, partially refit it into the bike and tighten the
lower clamp bolt. Using a piece of wood to prevent damage, tap the fork lower around the dust seal until it unsticks.
If you wish to wash out the fork, now is a good time. We used diesel and I have used paraffin before.
Pour a small amount into the fork and pump it a few times then drain. Repeat till you think you've got most of the gunge
out. DON'T bottom the fork out!
Next loosen the damper assembly nut located in the bottom of the fork. If you managed to loosen it earlier this
should be quite a simple stage, if not then this is difficult as the damper assembly will most likely rotate in the
fork itself.
You will need to find something to put inside the fork to try and jam the damper assembly - a broom handle or a piece
of wood with a tapered end works best.
Upend the fork and place it over your pole, force the fork lower down so that the pole grips the parts inside and
then try and release the bolt. Be prepared to swear a bit and just keep trying. It took us 15 minutes to release
one, and the other just 30 seconds.
When the bolt is released, slide out the damper assembly.
The images below show what you are trying to do.
You should now have all the following bits from inside the fork:
Next prise off the dust seal to reveal the fork seal and retaining clip
Depending on how bad the dust seal was there may be a fair amount of gunk in here.
Next prise out the fork seal retaining clip. If you are not planning to replace it, take care not to damage it.
There are 3 'kinks' in the clip that you can use the get the clip out - the two by the open ends are best if you
can identify which they are.
Using a screwdriver (or other suitable tool) in the kink, lever the clip so that it opens and can be persuaded to
come out (as in the photos below)
If the clip is badly damaged or corroded it must be replaced.
Hold the fork lower in one hand and the fork upper in the other and give it a good yank.
This will pull the upper out of the lower and remove the old fork seal.
1 - upper fork bush
2 - washer
3 - old fork seal
Remove and discard the old seal.
Clean up the fork upper and lower and flush out any gunk.
At this point if you are going to replace the fork bushes, pry off the old ones and fit the new.
They are not continuous, but have a split so should come off easily.
Now take a new seal and rub a small amount of oil around the inner edge. Carefully fit the new seal
over the top of the fork. Be careful to get it the right way round. The 'open' side faces inside the
fork and the closed side faces outwards.
View of the 'open' side which faces inwards/down
View of the 'closed' side which faces outwards/up
Refit the fork inner into the outer. The bush may or may not slip in easily. If it wont go in all the
way don't worry as it will be pushed in when we drive the seal in.
Using your seal driver tool hammer the seal home.
When the seal is fully seated you will be able to see the retaining clip groove all around the fork lower.
Refit the retaining ring and the dust seal.
Next refit the damper assembly - make sure the rebound spring does not come off in the process.
We found (as in the pics above) that it was easier to insert the damper assy from below. Insert the
retaining bolt and tighten it to the correct torque.
Next refill the fork with the correct amount of fork oil as specified in the manual. The manual
specifies 10W fork oil, but many fazer owners (myself included) use 15W as it makes the front forks
less bouncy.
The fork inner must be fully inserted into the fork lower to do this - remember the risk of getting it
jammed so DO THIS VERY CAREFULLY!
Fill the fork with slightly less oil than required (440ml instead of 475 as needed). Pump it a few times to
remove any air trapped around the damper assembly. (Do not pull the fork inner out by more than 130mm or you
will cause more air to enter)
Leave the fork for about 10 mins to let any air bubbles rise, then Measure the air gap and add oil as needed.
Keep repeating until you have got the correct air gap.
To get the correct air gap you can either use a rod or micrometer depth gauge and carefully fill the fork
until the oil just touches your measuring rod, or you can make up a tool like I did.
The rigid (bit of old metal brake pipe or hollow car aerial) tube is set to the correct air gap, the fork
is slightly overfilled with fork oil and then the tube is inserted. The suction bulb is then used to suck
out the excess oil.
When you have the correct amount of oil in the fork, pull the fork inner up (no need to worry about air now)
and insert the spring and spacers making sure you get them in the right order. Refit the fork cap bolt- this
is a little tricky as you have to depress the fork spring at the same time.
Refit the fork into the bike, making sure the top of the fork is just level with the top of the top yoke, and
tighten the lower clamp bolt. Before tightening the top clam bolt, correctly tighten the fork cap nut.
Now tighten the top clamp bolt.
Repeat for the second fork.
Refit the front wheel - take extra care to make sure the two lubs on the inner part of the speedo sender unit
are correctly located or they will snap off.
Refit brakes and fairing.
Job done!!!