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the manual calls for between 30 and 35 mm chain slack. going up and down with minimal pressure say about 5 pounds of forse i have about 40 mm. I read in hear that its better to be loose. at what mesurement do you feel its time to adjust it?
 

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I am constantly adjusting my chain all the time, I do it by look & feel. If in doubt I adjust it. Better to leave some slackness in there, as when you sit on the bike, it will take a little slack out.
 

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Loose is better than too tight. Can lose a output shaft bearing running a chain to tight, among other possible problems.

When you check your slack adjustment try to do it setting on the bike, or have someone set on the bike and double check your slack.

I made a tool out of rebar so I can sit on mine an pull up on the chain to see slack. Works pretty good.
 

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Loose is better than too tight. Can lose a output shaft bearing running a chain to tight, among other possible problems.

When you check your slack adjustment try to do it setting on the bike, or have someone set on the bike and double check your slack.

I made a tool out of rebar so I can sit on mine an pull up on the chain to see slack. Works pretty good.
:+1: I seriously almost never adjust my chain, only try to keep it clean
 

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clean and check my chain every 4hundy. chain tension is important so check it often, especially if it's new. better to be a little loose but in the manual it calls for between 1.2 and 1.4" of play (measured mid way between sprockets from the lower chain). good idea to measure with you on bike because it will tighten up when loaded. too tight = engine wear :sad: and too loose = chain wear (which could lead to failure). chain failure at speed could be very very bad.

search around, there is a pretty good couple of threads discussing chain tension adjustment as well as rear wheel alignment.
 

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Ummm, Something should be mentioned I guess. Something has to be kept in mind, as a chain starts to need adjusting. Chains don't show slack evenly, so... you (to be safe) need to find the tightest spot on the chain sprocket rotation, and do your slack adjustment there. When you know that is the tightest spot, there is no need to favor the loose end of the slack scale.

You definately need to have stress free slack, but excess slack isn't good either. By the way condition of the chain is easily monitored by trying to pull on the chain, to see if it will move, straight back from the center of the rear sprocket. A new chain and sprockets won't get a trace of movement there (even with correct slack in the chain adjustment) and as the chain deteriorates, you can get (see) the chain move from the sprocket. Different people have different concerns there, but, 1/16ths of an inch is a start of concern, and 1/8th of and inch is over due for chain and sprocket tossing, in my mind. Trying to extend it's use, isn't worth the having put it off too long.
 

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Ummm, Something should be mentioned I guess. Something has to be kept in mind, as a chain starts to need adjusting. Chains don't show slack evenly, so... you (to be safe) need to find the tightest spot on the chain sprocket rotation, and do your slack adjustment there. When you know that is the tightest spot, there is no need to favor the loose end of the slack scale.
Having a loose spot and tight spot in your chain is NOT normal. If that's the case then you need a new chain(and sprockets). :headshake
 

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Ummm, Something should be mentioned I guess. Something has to be kept in mind, as a chain starts to need adjusting. Chains don't show slack evenly, so... you (to be safe) need to find the tightest spot on the chain sprocket rotation, and do your slack adjustment there. When you know that is the tightest spot, there is no need to favor the loose end of the slack scale.

You definately need to have stress free slack, but excess slack isn't good either. By the way condition of the chain is easily monitored by trying to pull on the chain, to see if it will move, straight back from the center of the rear sprocket. A new chain and sprockets won't get a trace of movement there (even with correct slack in the chain adjustment) and as the chain deteriorates, you can get (see) the chain move from the sprocket. Different people have different concerns there, but, 1/16ths of an inch is a start of concern, and 1/8th of and inch is over due for chain and sprocket tossing, in my mind. Trying to extend it's use, isn't worth the having put it off too long.
Yeah I think you may have a problem with your chain. The cause of those tight spots are kinks in the chain. That tells me one of 3 things.

1) Your chain needs to be lubed.

2) Your chain has a lot of grit in it and needs to be cleaned and thoroughly lubed.

3) Your chain is getting old and is getting bad spots in it.

Often times people would bring their bikes into the shop like that and the chains were in desperate need of TLC. After cleaning them really well and lubin er up good, it got a lot better (even on a worn out chain). I'd definitely suggest giving a good inspection on your chain and even look to the sproket to see how bad your teeth are wearing (pulling front to back).

In regards to the first post, its okay to have a little extra slack if you are checking the bike while not sitting on it (Which is how the measurements are made). Most people don't fit the standard rider of 135 lbs that it states in the manual. Therefore with me being 185 lbs, I need a little more slack than they call for. Best thing to do is sit on the bike and get a feel for it. I usually sit on it and try to get about a good inch (1in=25.4mm) or a little over of play in it. As far as when to adjust, you just need to keep an eye on it. I'd say give it a look every 200 miles or so unless its brand new. A new chain could be adjusted after 50 miles honestly.
 

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Yeah I think you may have a problem with your chain. The cause of those tight spots are kinks in the chain. That tells me one of 3 things.

1) Your chain should have been lubed a long time ago and needs to be Thrown away and replaced..

2) Your chain has a lot of grit in it and needs to be Thrown away and replaced.

3) Your chain is getting old and is getting bad spots in it and needs to be Thrown away and replaced..
Hope you don't mind, I edited your post
 

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As far as sitting on the bike when you check the tightness... the service manual and owner’s manual specifically says do not sit on it and it should be on the side stand. Here’s why...

With the recommended slack in the chain as the bike compresses the rear suspension and the swing arm “rises” in relation to the lowering of the bike the chain will, for a few degrees of angle, tighten slightly. As this progresses further, the centerline of 1. The front sprocket 2. The swing arm pivot and 3. The rear axle (being center of the sprocket) is exceeded and the chain will begin to loosen as the distance between these 3 points is now shortening. About the point where these stop, or where the rear suspension bottoms out, the chain returns to having approximately the same amount of slack as before compression. Don’t believe it? Put your bike on a frame stand and disconnect the lower portion of the shock assembly, then raise and lower the swing arm while feeling the chain slack.

They say do not sit on it because they expect the rear suspension to be fully extended (minus a little minuscule sag possibly) thus the suspension will never exceed this position riding it. The recommended slack is thus computed and needed to compensate for when these 3 points are at their furthest distance, which is inline with each other.

The people that write these manuals know what they are talking about. Cheers! :beer:
 

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Dan, correct me if I am wrong but it seems the reason you are saying you should NOT sit on the bike is the reason others are saying you should. I adjust my chain not only sitting on the bike but reaching down and pulling on the rear wheel to flatten the swingarm out as much as possible. IF you adjusted the chain to factory spec the chain slack would limit your suspension travel. (i.e. the shock could never fully compress because the chain would tighten around the sprockets and prevent the swingarm from travelling to it's farthest point.
 

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I'm with Lawdog but there again I kinda see what you are saying. Are you saying the slack required at sitting on the side stand is such that when the rider is on the bike, that the chain is taught? Because I know when I've done the bikes per spec and a small guy (normal rider from factory's eyes) has gotten on the bike, there is a decent amount of play still in the chain. This being said, it ends up being about 1.25 inches. So that's how I came up with my estimate. I'm really not sure that either way is going to have you bad off from where the chain should be.
 

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Question?

Just wondering if there is a difference between adjusting on the side stand verses using a swing arm stand. I've always used a rear stand to get the rear wheel off the ground so the wheel could be rotated checking at different points on the chain. :dontknow:
 

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Just wondering if there is a difference between adjusting on the side stand verses using a swing arm stand. I've always used a rear stand to get the rear wheel off the ground so the wheel could be rotated checking at different points on the chain. :dontknow:

When you put the bike on the rear stand it shifts the weight to the front end a little more and therefore doesn't end up exactly the same. I notice chains do get a little tighter when the bike is sitting upright in a wheel chock. In comparison to sitting on the side stand, that takes a lot of weight off of the suspension so yes there is a difference from sitting upright and leaning on its side. There again, it isn't night and day differences though. Just a slight change.
 

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I believe I see your concern, which is basically the more weight I put on it the tighter it gets so you are trying to replicate that by sitting on it a trying to bottom out the suspension.

What you will end up with is a chain that is too loose. Do this. Set the correct slack on the chain with it on the side stand, then have a buddy or two sit on the bike until the front sprocket, swingarm pivot, and the rear axle are inline then feel the chain again. It's has tightened up to the maximum allowable tension the factory has deemed safely allowable. Put a little more weight on it and you will see the chain will begin to loosen again as these 3 points very slightly get closer together due to the pivot of the swing arm.

And you can set the chain slack while on swing arm stands, just slightly lift up on the rear to ensure there is no sag. Unless your rear shock/ spring assy is shot, there should be little to none with no one on it. Like I said, once you see it with the rear shock disconnected it, it all makes sense.

But a looser chain will usually always cause less problems than a tight one! Atleast cheaper problems anyway!




Dan, correct me if I am wrong but it seems the reason you are saying you should NOT sit on the bike is the reason others are saying you should. I adjust my chain not only sitting on the bike but reaching down and pulling on the rear wheel to flatten the swingarm out as much as possible. IF you adjusted the chain to factory spec the chain slack would limit your suspension travel. (i.e. the shock could never fully compress because the chain would tighten around the sprockets and prevent the swingarm from travelling to it's farthest point.
 

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Sounds like we are describing doing the same thing, just different means of doing so. I think I understand the idea that the tightest point is when both sprockets are in a straight line with the swingarm pivot and after passing that point the chain is getting more slack in it right?
 

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Bingo!:idea:

Sounds like we are describing doing the same thing, just different means of doing so. I think I understand the idea that the tightest point is when both sprockets are in a straight line with the swingarm pivot and after passing that point the chain is getting more slack in it right?
 
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