Chain length

[Micro]

Hi guys, a few nights ago my chain was that loose that it jumped off the sprocket a few times. Lucky enough i was only about a mile and a half from home so i was able to put it back on again  every couple of hundred metres when it came off again. It was about a month since  i checked the chain  which seems to be streatching badly.  Anyway,  my rear sprocket now is buggered so im ordering a new one. I know its 44 T / 520 pitch but what size of a chain do i need, front sprocket has gone up one tooth and rear will be standard.  Thanks .     ..... Davy..... 🚵   
I think the standard chain is 110 links will this fit with the extra front tooth socket (15) or would i need a 112 link one.

[Taught2BeCautious]

I am still using the factory original chain on mine and often swap between 13T and 15T front sprockets with no problems.

A common error when checking and adjusting the chain, is to do it with no weight on the back wheel - so when you sit on it, the chain becomes too tight causing it to stretch and wear out quickly.

You will probably need someone to help you (or a mirror) the first time, but take the bike off the stand, sit on it and put your weight over the rear wheel until the centre line between the front and rear sprockets lines-up with the centre of the swing-arm pivot.

Check the chain slack in the middle of the bottom run and rotate the wheel to check it in 3 or 4 different positions, and repeat after adjusting.

[Micro]

Thanks  T2bc, i'll order the 520 / 110 chain and a new rear sprocket. I did adjust the chain with no weight on it so thats probably what stretched it. 😱  if i adjust the chain with someone sitting on it wont this make it harder to move the rear wheel. Probably a silly question but if u dont  ask u never find out.   .....Davy......🚵

[mozza83]

A common error when checking and adjusting the chain, is to do it with no weight on the back wheel - so when you sit on it, the chain becomes too tight causing it to stretch and wear out quickly.

Do the handbook chain settings not take into account the change in tightness when someone (albeit probably a 65kg Japanese man) sits on the bike. I always thought that to set the chain tightness to the handbook setting while sitting on the bike would make the chain run very loose.

[Taught2BeCautious]

Under ideal conditions, the centres of the front and rear sprockets and the centre of the swing-arm pivot (points A, B and C) should all line-up when you are sat on the bike - and this is the position where the chain will be at it's tightest.

This is also the position where points A, B and C will be for most of the time you are riding the bike normally, so it makes perfect sense to check the chain adjustment in this position only.

As the rear wheel moves up and down as you ride over bumps and potholes, the chain will be slacker than normal - which means that if you have checked the chain tension when the rear wheel is in it's lowest position, it will be far too tight when in the normal position.

The pre-load adjuster on the rear suspension unit allows you to compensate for different rider weights, so you can achieve a straight line through A, B and C when you are riding the bike normally.

I'm not sure exactly what the manual says, but the diagram shows the only possible position where the chain could be checked for slack, because there would be no way of knowing how rider weight, luggage, suspension settings, etc. would affect the alignment.

The reason for checking the chain in 3 or 4 different positions, is to ensure that there are no tight spots that would affect it.  You can easily do this whilst sitting on the bike - with your right hand covering the front brake, simply scoot the bike forwards and backwards a foot or so from the original position, and reach down and check the slack with your left hand (or get someone else to check it).

Now that I have done it a few times, I check and adjust mine with the bike on the centre stand, and the rear wheel  in it's lowest position, but using a different measurement to the one stated - then when I'm sitting on the bike and points A, B and C are aligned, the amount of slack is spot on!

[mozza83]

I see, it would be a real pain in the arse to adjust like that with my paddock stand so I'll bear it in mind for when a centre stand comes my way

[BigYin]

the way I worked out what to adjust my chain to when on the stand was simply to get a mate to measure the slack while I sat on the bike, feet up so full weight was on the bike (leaning one hand against the wall to maintain balance). After a few cycles of jump off, adjustment, then jump back on and recheck, we had it pretty much right, then put the bike on the stand and measured again - that LAST measurement is the one I now adjust the chain too.

So you only have to go through that pain once, get it right, jump off and measure, and then note that, and adjust to that in future 

[black rider]

this sounds like a plan  . I will  put on my riding gear and top box with its usual contents in it I am sure it would make I difference . I know my top box and all that lives in there usually  weighs 2 stone . my leather jacket and trousers are quite heavy too  they must weigh another 2 stone  between them