CHAINS AND SPROCKETS

Chains and Sprockets : Adjusting the Chain Tension
According to the manual, correct chain tension is about 30-40mm slack with both wheels on the ground, and no rider on board.
However, holding the bike upright, and either measuring or adjusting the tension is a bit of a tricky task for those of us with only two arms, so I generally check it while on the sidestand, and then if it needs any adjustment, I work out how much, and then put it up on the mainstand to adjust. I'll then recheck it on the sidestand, and repeat the whole process as necessary until it's right.

You need to loosen the rear axle nut (not too much), and the locknuts on the adjusters.
It's also a good idea to loosen the rear brake torque arm bolt (where it bolts to the caliper hanger) as well.

Adjustment is a case of turning the adjuster nuts to pull the wheel spindle back until the chain tension is correct. Of course, doing this introduces the possibility of upsetting the wheel alignment, and to keep this correct, you've got a set of little notches on the swinging arm; it's a case of checking that the same number of notches (and part notches) are visible in front of the washer either side of the swinging arm.

Beware, though, not to just heave one side back through two or three turns of the adjuster, and then go round the other side and try and do likewise. If you do this, you'll almost certainly end up overtightening one side, which will mean loosening it off and pushing the wheel forwards again (this is where loosening the torque arm - which shouldn't, but can present a fair bit of resistance to the wheel going forwards again - comes in).
I find it best to turn the two adjuster nuts by the same, small amount (around 1/3 turn each time) and then check the tension. Doing this means each side is going back by the same amount, which should maintain the wheel alignment as it was when you started. Which, if it was correct, will mean it's still correct.

Having got the chain tension correct, re-tighten the axle nut (to 117Nm), and re-check the chain tension. Also check that the swinging arm end caps (against which the adjusters tighten) are firmly held in place.
If you're lucky, all will be ok, but often this is the point at which people often find it goes out, because things have moved in doing up the nut.
If the tension is OK, but one or both caps is loose, check the position of the washers on the spindle relative to the adjustment marks. If both sides match, just turn the relevant adjuster nut until the cap is tight again. If both sides don't match, you need to loosen everything off and do it all again.
It's not uncommon for it to take a few goes - pain in the proverbial, but an incorrectly aligned back wheel will lead to accelerated chain/sprocket and tyre wear, and probably handling problems too, so it's worth taking the time.
Best advice I can give is only loosen the axle nut just enough that the adusters can move the spindle. The more you loosen it off, the more effect tightening it back up is likely to have (in my experience).

Now that you've got the chain tension right, and the axle nut done up, you're nearly finished.
Re-tighten the brake torque arm bolt if you loosened it - to 23Nm, and then tighten the adjuster locknuts. For the locknuts, you need to hold the nut nearest the swing arm steady with a spanner, and tighten the other one against it, so that they cannot come undone. The locknuts should be tightened to 16Nm.

Finally, say a quick prayer, then check the tension again and double check that you've done up the axle nut, the torque arm nut and the adjuster locknuts.

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Chains and Sprockets : Chain Tension - Why it Matters
Why should there be 30-40mm slack in the chain? What's the significance of that?

Well it's like this. Chains don't like to be too tight.
If they are, they get hot; the oil in o-ring chains will become thin and stop doing its job properly - perhaps even becoming
thin enough to find its way out past the o-rings. The chain will wear quicker, and there's an increased possibility of
mechanical failure of the chain - not nice.

On the other hand, the rest of the bike doesn't want the chain to be too loose. If it is, then it can rub on the swinging arm -
wearing the arm, and generating heat in the chain (see above). It will also, because of the centrifugal forces at work, end up
sitting on the outer, thinner parts of the sprocket teeth - which will accelerate wear to the sprocket.

So hopefully the need for correct chain tension becomes clear. But why '35-40mm on the sidestand', or whatever?

Well bear in mind that your swinging arm pivots about a point which is typically a few inches behind the front sprocket.
So it's not like a straightforward pendulum, where the chain tension remains constant throughout suspension travel.
The point at which the chain is under maximum tension is when the front sprocket centre, the swinging arm pivot centre,
and the rear wheel spindle are all in a line - somewhere in the middle of the suspension travel.
And at this point, people who know chains recommend about half an inch of up and down chain movement to avoid the chain
becoming overtight and damage occurring (don't ask me how I know - I just do).

Now you could adjust your chain like this - if you've got a couple of large mates handy to sit on the bike and compress the
suspension, or use a ratcheting tie-down looped over the seat and under the swinging arm, until things are lined up like this
and then adjust for that half-inch of play.
But the bike makers realise that this is not really practical for everyone, so they give a figure of so many millimeters of play
at a certain suspension travel - for example on the centre stand (suspension unloaded), or on the sidestand (suspension partly
loaded) - which will give this half-inch as the suspension passes that mid-point.

And that's where your '35-40mm on the sidestand' - or whatever - comes from.


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Chains and Sprockets : Checking the Chain Wear

Two things you're looking for are:
(1) Tight spots, and
(2) 'Stretched' chain.

Tight spots usually occur when a chain's overheated (probably through insufficient lubrication) and one or more link has siezed. The upshot of this is the affected links either not wanting to curve around the sprocket, or not wanting to straighten up once they come off it - either way resulting in tight spots in the chain. Sometimes they can be freed - depending on how badly they've siezed. Take the back wheel off, find the affected links, and work them - working plenty of oil into them - until either they loosen off a bit, or you realise it's a lost cause and decide to replace the chain.

A stretched chain is what happens eventually if you manage to avoid tight spots ruining the chain. The chain doesn't actually stretch; it's more a question of wear to the pins and tubes where the links meet.
A quick and easy way to measure how stretched your chain is is to grab a link at the 3 o'clock position on the rear sprocket, and try to pull it backwards away from the sprocket. If it'll come away far enough that you can get a pencil between the chain and the sprocket, it's about ready for replacement.

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Chains and Sprockets : Standard Sizes
Standard sprocket sizes are:
Front: 15T
Rear: 48T
The chain is an endless (rivetted) item, 110 links. Split links should NOT be used; replacements should be supplied with a soft link which should be used for fitting.

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Chains and Sprockets : Effect of Changing
I put together this spreadsheet to make it easy to work out theoretical speeds for a variety of gearing.
Just type in the front and rear sprocket sizes and the rear tyre size in the relevant slots (the grey boxes), and the tables below them will give speeds at various engine revs.
The blue set of numbers is standard gearing; the red ones are with the specified gearing - so you can see how they compare.

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Chains and Sprockets : Suppliers of Alternatives
So far, these are the places I've bought from. Both have been knowledgeable regarding the various options for a Fazer 600, and both have provided a good, quick turnaround:

Trade Direct: tel 08705 134859.
May 2003 prices: X-Ring kits (X-ring DID chain and sprockets) for 79.99 or O-Ring kits for 64.99

B&C Express
Station Road,
Potterhanworth,
Lincoln,
LN4 2DX,
ENGLAND
Tel: 01522 791369
E-mail: sales@bandcexpress.co.uk
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Chains and Sprockets : Front Sprocket Nut
The front sprocket is held on with a 32mm nut, and a security washer. It is wise to replace the washer every time the nut is undone - you don't want it coming undone at - ahem - mph, and there have also been stories of them coming just a bit loose and destroying the thread on the gearbox output shaft - a pricey one to put right.
The nut is tightened to 70NM torque, which in laymans terms is 'FT' (clue - the second word is 'tight'). This means it'll be a tough one to get undone - be warned.
I've known of a couple of approaches being taken to getting it off. The first is to stick a fairly thick bit of wood between the swinging arm and a wheel spoke which is soft enough to deform against them, (hugely preferable to them deforming against it), yet thick enough that it won't just snap in two.
The second requires two people - one standing on the back brake while the other puts his back into trying to turn a long breaker bar.

Whichever method you use, I'm reliably informed that when it goes, it goes with a serious 'crack' that'll have you thinking something's just broken. So be warned - bit scarey.

Good luck.

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Chains and Sprockets : Spray-on Chain Lube - why does it always fly off?
The problem here is two conflicting demands of spray-on chain lube.

The first is that to keep it on the chain, it needs to be sticky.

The second is that in order for it to (a) get out of the can and onto the chain, and then (b) to find its way
around the chain and into the links which need lubricating, it needs to be runny to do this.

The solution to this conflict is that the lube, as it comes out of the can, contains solvent which makes it runny.

After it's been out of the can for a while, this solvent evaporates, leaving behind a thick, sticky lube.

So of course, if you ride off before this has happened, then the same runny-ness which helps the lube find its way
around the chain will make sure it doesn't stick to the chain once it starts whizzing round, and good old centrifugal
forces will redistribute the lube onto the underside of your seat, the inside of the gearbox sprocket cover, and - if
you're really lucky, your boots, trousers, etc, etc.

So the answer is pretty simple - give the lube time to 'cure' before riding. Somewhere in the region of 20 minutes
between lubing and riding should be long enough for the magic solvent to evaporate, and your lube to stick itself
where you want it to stay.

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