New chain a *bit* too tight, should I bother to loosen?

**Wasp** · 19th February 2007, 08:38

With the help of Maximusder... I put a new chain on the Bandit last night - we had a bit of trouble but got there in the end

thing is its still a little tight, its not like there is no slack but im still worried

should I bother to loosen it a bit?

(big thanks to maximusder... for helping with the chain and koba for spending his morning helping me fit new clutch plates)

**Disco Dan** · 19th February 2007, 08:48

"it is touit, touit like a tiger no?"

...depends if you want it to snap or not.

**Crisis management** · 19th February 2007, 09:28

Adjust it to the correct amount of slack (25- 30 mm of play in the lower strand)?

I have had an overtight chain bring a 750cc bike to a stand still due to overheating. So, yes, it is important.

**Kwaka14** · 19th February 2007, 09:31

If it's too tight it will destroy the g/box output shaft bearing, make sure there is the reccomended play when your on the bike, probably somewhere around 20-30mm total movement.....

**vifferman** · 19th February 2007, 09:42

Better too loose than too tight. If it's too tight, it will make gearchanges worse, prematurely wear the chain, and interfere with the suspension movement.

**alexthekidd** · 20th February 2007, 18:01

your bandit now has a clutch?????????!!!!!!!!!!!!!!!!!!111

**bugjuice** · 20th February 2007, 18:05

Originally Posted by Kwaka12R

If it's too tight it will destroy the g/box output shaft bearing, make sure there is the reccomended play when your on the bike, probably somewhere around 20-30mm total movement.....

ditto..
if there's a little movement (not too far off 20) then you might get away with it, but keep an eye on it

**Drum** · 20th February 2007, 18:20

It only takes 5 minutes wasp, so why wouldn't you?

**Wasp** · 20th February 2007, 20:19

Originally Posted by Drum

It only takes 5 minutes wasp, so why wouldn't you?

you pretty much summed it up right there

Originally Posted by alexthekidd

your bandit now has a clutch?????????!!!!!!!!!!!!!!!!!!111

yup and oil and filter too so shes all mint now, price going up

it moves atleast 2 chain heights above its resting position, dunno, will keep an eye on it

took it at motorway speeds today

**TonyB** · 20th February 2007, 20:33

The chain will be tightest when the front sprocket centre, swing arm pivot and axle are all in a straight line. If you are worried the chain is too tight, find some fat bastards to squash the suspension down till everything lines up as described, then check to see if the chain is really tight- it shouldn't be.

If your chain is too tight, the suspension won't move freely, infact it may not compress past the point described above. If it is too tight and the suspension DOES manage to compress past this point, it'll stretch the chain. Not good. Not every one will agree with this, but I reckon thats why bikes end up with chains with tight spots. Ever hear a bike go past going rrRRrrRRrrRRrrRRrrRR? thats the tight spot in the chain.

**Madness** · 20th February 2007, 20:35

Originally Posted by TonyB

find some fat bastard to squash the suspension down till everything lines up as described, then check to see if the chain is really tight-

Sigh, Bring it back & I'll sit on it for ya.

**riffer** · 21st February 2007, 07:32

Not to mention that there's an awful lot of stress on the output shaft bearing if the chain's too tight as well.

Moral of the story - get your chain tension right, or fuck your bike. Your choice.

**idleidolidyll** · 21st February 2007, 07:46

Originally Posted by Wasp

With the help of Maximusder... I put a new chain on the Bandit last night - we had a bit of trouble but got there in the end

thing is its still a little tight, its not like there is no slack but im still worried

should I bother to loosen it a bit?

(big thanks to maximusder... for helping with the chain and koba for spending his morning helping me fit new clutch plates)

as you have already been informed, an overtight chain can wreck your gearbox.
it can also ruin your ride quality by binding up the suspension.

the main idea of chain slack is to have the chain JUST tight enough so that it both rolls freely and doesn't bind the suspension and strain the gearbox/output shaft.

I'v found over the years that even manufacturers recommendations can be incorrect and i now check chain tension in a more scientific way.

Here it is:
Steady the bike in an upright position by it's handlebars tied to each wall, don't pull down on the bars.

throw a ratchet style tie down (one of the truckie ones if possible, they're stronger) over the seat at the back and as far back over the swingarm as possible. Loop it through the swingarm being careful not to pinch cables or brake lines etc. Ratchet down the rear suspension until all 3 of the centres of the front sprocket, swingarm pivot and rear sprocket are exactly in line.

That is the longest your chain will need to be. At that point, adjust the chain so that it is almost tight but not quite, maybe about 5-10mm slack.
This will ensure that your chain will not bind the suspension, stress the output shaft or wear itself out prematurely.

Of course you should also check whell alignment with a stringline if you can: there is no reason to believe that the marks on the swingarm to adjust the chain are actually equal or in the right place on both sides.

**TonyB** · 21st February 2007, 17:01

Originally Posted by idleidolidyll

I'v found over the years that even manufacturers recommendations can be incorrect and i now check chain tension in a more scientific way.

Same! Why the hell do they do that??? I have buggered up a chain by following the manufacturers recommendations. So I started doing something similar to what Idle describes above. On some bikes when the chain slack is right it will actually seem very loose with little or no load on it- my old FZR1000 was like that. Get it right and your chain will last for years.