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Hi,
I think I need to tighten my chain. Do I need to have the rear wheel up on a paddock stand to do that ?

Cheers Rob
 

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No. Just loosen the wheel nut and wind the tensioner bolts (next to the rear axle bolt) out till you have 3-5mm chain slack (unloaded). The tool kit has everything you need.
 

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The sticker and the owners manual give a low value for chain slack. If you use this value make sure you measure it with the suspension compressed. If you don't have someone to help you can either stand on the right hand side of the bike and put your weight across the saddle then reach down to the chain, or, if you're not that kind of contortionist, you can use a bike tie down strap ( the kind with self gripping buckles ) wrapped round the wheel rim and the seat to compress the suspension.

It is easier with a paddock stand, which you also need to apply chain lube easily.

Too tight is generally more harmful than too loose. A tight chain will wear itself and the sprockets and will eventually damage the gearbox bearing and seal.
 

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I agree with roadster. I have adjusted my chain so that it has 15 mm slack loaded. I have found that this reduces the amount of chain slap, and provides smoother gear changes. If you want to follow the maintenance manual advice and set the slack at 5-7 mm, this should be done with the bike loaded by the rider.
 

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I agree with roadster. I have adjusted my chain so that it has 15 mm slack loaded. I have found that this reduces the amount of chain slap, and provides smoother gear changes. If you want to follow the maintenance manual advice and set the slack at 5-7 mm, this should be done with the bike loaded by the rider.
The thing is, and I checked the sticker and manual to make sure, the quoted 5-7mm isn't for chain "slack", it is the distance between the swing arm and the chain when pushing the chain upwards. I realize this is not the usual way that required chain slack is indicated on motorcycles. Although it is somewhat easier to eyeball as it is a "static" measurement (push up, look at distance between chain and swingarm) vs. trying to gauge how much the chain is moving.

The arrows on the figure are pretty clear as to what the measurement is.
 

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My EXC is the same mate, grab it at a certain point and lift. With both KTM's I use the same method, find one point and use that as my eye guide. Never experienced this chain slap that people have mentioned all over the forums.
 

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My EXC is the same mate, grab it at a certain point and lift. With both KTM's I use the same method, find one point and use that as my eye guide. Never experienced this chain slap that people have mentioned all over the forums.
Yeah, looks like that's the "KTM way". It also means that a smaller number means more slack (able to push the chain closer to the swingarm).
 

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The problem is that the chain and cush drive construction means that its fairly elastic and it really depends how much force is applied. In any case it is definitely necessary to have enough compression in the suspension to be checking at the point of maximum tension (i.e. minimum slackness).

I think the slapping noise probably comes from the top run when the drive is unloaded. It seems to happen when the throttle is closed or on the overrun and when the road is choppy.

The diagram and arrows are not actually very clear at all. Taking the one in the workshop manual as an example the tips of the arrows only point vaguely to the chain and swing arm so I don't think its meant to be taken too literally. It seems reasonable to interpret it as saying that the chain may come within 5mm of the bottom of the swing arm and we have to assume that this means at the position of minimum slackness. Finding that position without a rear stand would be impossible though.

Conclusion: Its down to experience! But I still say that too tight will do more damage than too slack.
 

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Hi everyone, I did a chain check and oil 300kms, in Aus here, was slack as, no chain slap, but was near hitting swing arm, not quite. Is this normal stretch for new chain, considering it was correct tension at new..
 

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What about general noise from the chain? I lubed it up enough to spray a nice mess on my rear rim, but it still sounds noisy when letting sound up between the tank and my thigh.

Is this normal to hear? What's the remedy?
 

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Its advised too but I dont.
False, it must be done on the ground.

No. Just loosen the wheel nut and wind the tensioner bolts (next to the rear axle bolt) out till you have 3-5mm chain slack (unloaded). The tool kit has everything you need.
False, you need a torque tool.

Just make sure you move the wheel and check the tension at few points and not just one.
True.

I agree with roadster. I have adjusted my chain so that it has 15 mm slack loaded. I have found that this reduces the amount of chain slap, and provides smoother gear changes. If you want to follow the maintenance manual advice and set the slack at 5-7 mm, this should be done with the bike loaded by the rider.
Every chain tension adjustment must be done with rider and all the weight.
 

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A properly tensioned (and mantained) chain MUST not make sounds and not "slap" the swingarm.

And a last thing, the sticker SUCKS, all KTM mechanics told me you must adjust the play, not the distance in between. As the manual suggest.
 

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.... 3-5mm chain slack (unloaded)....
....15 mm slack loaded........ set the slack at 5-7 mm...
...... 5-7mm isn't for chain "slack", it is the distance between the swing arm and the chain when pushing the chain upwards. ...
The arrows on the figure are pretty clear as to what the measurement is.
...the sticker SUCKS, all KTM mechanics told me you must adjust the play, not the distance in between. As the manual suggest.
Doe's anyone have some advice about this? I am no mechanic, but I should be able to check the chain tension. I find the figure in the owners manual to be confusing, it is the same figure that is present on the swing arm of the 2016.When pushing the chain up at the designated spot, with no load and in neutral, is it the distance from the top of the chain to making contact with the swingarm; or is it the distance from the top of the chain to the outer lower edge of the swingarm? The manual doesn't say. The picture looks like the arrow points to the outer lower edge, but my chain pushes up behind that lip and has around .2" to making contact with the swingarm. I have 100 miles on it.
 

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Here is my chain when pushed up at the indicated spot. Top of chain is tight. The chain goes behind the lip of the swing arm, but it does not quite make contact.
 

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you dont have to lift rear in order to adjust the chain. Just unscrew a little the rear axle nut and adjust the small nuts. Like other members said, the rear axle must have same distance left and right, in order to be completely aligned with the front wheel. Better a little loose chain then very tight.

The chain slaps when it is loose.
 

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you dont have to lift rear in order to adjust the chain. Just unscrew a little the rear axle nut and adjust the small nuts. Like other members said, the rear axle must have same distance left and right, in order to be completely aligned with the front wheel. Better a little loose chain then very tight.

The chain slaps when it is loose.
Thanks, but my issue is not with adjusting the chain, it is with determining the correct tension in the first place.
 

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As has been posted here, the best way to check chain tension is to load the passenger seat/grab handles as hard as you can with your body's weight and make sure the chain is not (quite) tight. This is tougher when the bike's on the sidestand, so I usually put ours on a rear wheel stand. A heavyweight helper is also useful; I have a riding buddy neighbor who weighs ~70 pounds more than I do.

Also, if you have changed the rear shock the unloaded slack would vary with the length of the new shock. But the 'full load' method still works fine.
 
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