SUSPENSION

Suspension : Overview
At the front, it's conventional telescopic forks, containing coil spring and oil damping at the front, offering total fork travel of 120mm.
Early ('98 and '99) models feature no front suspension adjustment. From 2000 onwards, the front forks have featured adjustable preload. Alternative springs and (obviously) oil can be fitted to the front forks (see below).

At the rear, it's a single monoshock/linkage/swingarm, with a coil spring and gas/oil damping; the rear shock unit is adjustable for preload (9 positions) only (all models) and has a total of 50mm travel.

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Suspension : Front End Mods
The two more popular mods (if you can call them that) are dropping the front forks down through the yokes and oil and spring replacement.

Fork Oil and Spring Replacements
The recommended replacement, according the the FOC-U sages is Hagon progressive fork springs (from Busters - FOC-U members get 10% discount) and 15wt fork oil. If the forks are a bit floppy, the recommended action is to replace the oil first; if this still leaves something to be desired, replace the springs.

How to do it

The following is based upon the collective efforts of FOC-U stalwarts Alan Sherman (Bloke behind the Mods page), Ben Diesel (Very Nice Bloke called Brian), and Gnasher (Bloke Who Really Knows His Stuff):
Replacement fork oil is sold in different 'weights'; standard for the Fazer is 10 weight, or 10W as shown on the bottle, although some owners use 15W which is thicker and increases the damping.
The oil capacity is 475cc per leg for 98 and 99 models, and 465cc for 2000 onwards, so you'll need a litre bottle.

1. Before you start, squirt some penetrating oil (or WD 40 if you're stuck) on all the bolts you are going to need to undo, and leave for a while to soak in (as the forks are at the front of the bike, they cop all the rain and road salt and much, so the fasteners sometimes need a bit of help before you can get them undone);

2. Remove the front calipers, and suspend them so that there is no strain on the hoses (I use a bungee, with the hook through one of the bolt hoses, but string will do);

3. Loosen the front wheel pinch bolt and the wheel spindle;

4. Slacken off the preload adjuster completely (2000 onwards models), then loosen the fork caps (you won't be able to do this once the fork clamp bolts are undone). Now undo the fork clamp bolts a little - enough that you aren't stressing them when the bike is jacked up, but not so much that the wheel and forks fall straight out the moment you try to lift the wheel off the ground;

5. Put something under the downpipes so that the weight of the bike is supported with the front wheel off the ground. Make sure this is stable and reliable - the front end's going to be up in the air for quite a while and you don't want it coming down until you're ready;

6. Remove the front wheel (observing the points in 'Cautionary Notes For Wheel Removal');

7. Remove the mudguard (four 10mm head bolts);

8. Pick a fork leg and then, supporting its weight, undo the clamp bolts until it slides down and out of the yokes;

9. Remove the fork cap and spacer, then turn the fork leg upside down (over a container) and pour the old oil out of the fork leg - catching the washer and spring as they come out. Be sure to remember the order in which everything comes out;

10. Pump the fork slider up and down the leg (with the leg upside down) to expel as much oil as possible; you could even leave it to stand upside-down for a while if you like

11. You are now ready to refill the fork leg with the correct quantity and grade of oil. Now - In the words of Ben Diesel, "Getting the level right is the fiddliest bit of the job". I'll let him explain:

Oil levels vary between Fazer model years. Haynes quotes them as 121mm up to Y2K and 132mm Y2K onwards. This measurement is, in fact, the depth of the AIR GAP above the surface of the oil, measured from the top of the tube, with the tube fully compressed within the slider, without the fork spring in the tube. So, stating the bleedin' obvious here, fill the tube with oil and get the level right BEFORE you put the spring back in.

Getting the level right is the fiddliest bit of the job. As suggested above (by Alan Sherman, in the thread I nicked this bit from), pour in less than the specified amount of oil, then top up slowly to the correct level. The perfectionist method is to set a vernier caliper to the appropriate level (121 or 132 mm) and suspend it into the fork tube, resting on the top edge. Me, I'm not a perfectionist so I used a depth of cut gauge from an old mitre saw kit and it worked well.

Looking down into the tube is nigh on impossible without a miniMaglite torch or head torch. If using a hand-held torch, get someone else to hold it for you while you pour the oil.

As the oil level rises, look out for the meniscus (surface tension) of the oil breaking against the end of the depth gauge, then stop pouring. That's it! Insert spring and reassemble fork.

But before you do, Gnasher says to make sure you pump the fork leg at least 10 times before measuring the air gap.

Make it sound so easy, don't they?

12. Now you can re-assemble the fork leg - but before starting, one last warning from Brian:

Once filled with oil and the spring is back in, be careful to complete the reassembly without any cock-ups; cos if you have to take the spring out, you will have to do the oil level exercise all over again (when the spring comes out, it is covered in oil so the level in the fork will be too low).

You have been warned.

So...insert (in the right order, of course) the spring, washer, spacer and fork cap (hand tight for now), and then the leg back into the yokes and re-tighten the clamp bolts and then the fork cap. On models with fork pre-load adjusters, you will probably need to loosen off the clamp bolts and rotate one leg so both adjusters point in the same direction;

13. Repeat steps 8 to 12 for the other fork leg;

14. Refit the mudguard, front wheel and brake calipers (taking care not to damage the speedo rotor/sender or cable).

Job done.

So there you go. Cheers, chaps.

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Suspension : Rear End Mods

Replacing the Swinging Arm Bearings
Click here for pointer2null's excellent guide to replacing swing arm bearings

Shock Replacement
A number of companies make suitable replacement shocks for the Fazer; see the mods page on FOC-U for more details.

Shock Renovation
There are also a few companies around who will renovate your shock - yes, even the standard unit. This can include re-valving, re-springing and oiling (to your own specifications if necessary). Two such companies are:
Revs Racing & Suspension Services
Halesowen
West Midlands
Tel 0121 501 3321
http://www.revsracing.co.uk/revs/indexfr.htm

MCTechnics
(Authorised Ohlins service centre)
Stowmarket,
Suffolk
Tel 01449 775775
http://www.mctechnics.co.uk

but there's plenty of others about.
Jack-up Plates
Vokesy (Anthony) on the FOC-U board can supply aluminium replacements for the suspension linkage plates which will raise the seat by about 2-2½ inches, which helps with ground clearance, gives the shock a bit of help with two-up riding, and quickens the steering a bit.
They are CNC machined, so are all identical.
See this thread on the FOC-U message board for details

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Suspension : Setup Advice
The following is derived from a posting on the FOC-U board by Slidesvill:

The first step to set up any shock is with the Static Sag, this will give you the correct preload to use.
To measure the static sag is simple, but you'll need an assistant to help take some measurements and a pen and paper.

1. Place bike on centre stand;

2. Measure the distance between two fixed points (for example the top of the swinging arm and the bottom of the seat unit bodywork) - make a note of the measurement;

3. You now need to do the forks. With the back of the bike weighted sufficiently to lift the front wheel off the floor (get your assistant to push down on the back of the bike), measure the distance between the top of the fork slider (round the seal area) and the bottom yolk where it clamps round the forks - again make a note of the measurement;

4. Take the bike off it's stand, and sit on it as you would when riding;

5. Get your assistant to repeat the front and rear measurements, making sure that they measure from the same points, and make a note of the measurements;

6. For each (front and rear) measurement, subtract the larger of the two from the smaller - this will give the static sag. For the front this needs to be between 35 and 48mm; for the back it needs to be between 30 and 40mm. If the measurements are lower than this, you have insufficient sag - the preload is too high and should be reduced. If the sag is too great - your measurements are higher than these - you need more preload.
If you need further good suspension setup advice, there's some good stuff at: http://www.gostar-racing.com/information/motorcycle_suspension_set-up.htm <<-Back to Hot Poop Front Page


Suspension : Front Fork Alignment
The following method of checking your fork alignment (ie "are they twisted?"), courtesy of YamFazMan on the FOC-U board:

A simple way to check your fork alignment:-

Get two STRAIGHT lengths of tube or rod 12mm to 19mm dia about a Metre long
Then with the bike on the center stand turn the ignition switch to "unlock" and remove the key and straighten the steering.

Place one tube horizontal and centralized on top the black fork protectors that are fitted to the fork sliders, making sure it is contacting both fork stanchions.
Work the other tube between the control cables on the top yoke and then sit the tube on the top yoke in front of the fork legs and in contact with the ROUND part of both fork top caps (on later models you could sit the tube on the fork top nuts and back against the preload adjusters).

Then get on the bike standing on the foot rests and look down at the tubes they should be parallel if not the forks are twisted in the yokes or bent, the length of the tube exaggerates the error and make it easy to see.

What you do If the forks are only twisted and NOT bent

With the bike still on the center stand place a scissor-jack and a piece of wood under the exhaust pipes and just support the the weight of the bike.
Slack of the four capscrews (Allen screws) of the top and bottom yokes, the jack will stop the forks just sliding through the yokes.
Determine which way the forks are twisted in the yokes, then stand in front of the bike and grip the front wheel with your knees and pull and push the handlebars, until the tubes are parallel to each other, then re-torque the four top & botom yoke caphead screws.
Finally recheck the long tubes are still parallel to each other, Job done.


ATB YFM

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