Chain a bit tighter

[Sweaty_Doughnut]

Hi guys,

I took my NC750X DCT for a second service and noticed that the mechanic has set the slack to 25mm, while the manual says it should be between 30-40mm. Can I leave it as it is as I don't have any noise? I noticed that the manual version of NC750 has a slack between 25-35mm so I guess that's where the mistake came from.

[MCN]

I'm picky so would set to the spec for the bike, year etc.
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

[jaffa90]

Trail type bikes i`ve had many and the chain slack is more than other type bikes because of the long swing arm travel.
Just chock the side stand to near vertical and 2 on the bike both feet up and have somebody check the chain slack.
If it`s 30mm no less then check after with no load and it may be 50mm.
What have you got?????????????

[MCN]

https://www.youtube.com/watch?v=QpRilqORt-w
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

[davebike]

25mm is too tight
Many pro's set chains too tight maybe because it looks better or perhaps as it wears them out quicker
Losses it to at least 35mm after lubing it !

I am a pro but I always advise as lose as possible and as well lubricated as you can manage

Me fazer FZ6 chain at 40/50m turono lubricator using scottoil + sprey lub at least once a week ! Last chain did 38K miles
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Dave
NC750Xdct + others at work !
[email protected]

[stinkwheel]

You checking it at the tightest or most loose spot? Sometimes if there is a very big differ3ence between the two, I'll set it a little tighter at the tight spot to compensate for the excessive flapping about at the loose spot.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[jaffa90]

Lets see what slack he has loaded & unloaded on this model.

[MCN]

Find the right section and set the slack to that.

There must be a better way to find the correct setting as there is always debate over it.

Tracked equipment suffers the same argument.

At one time track tension (chain slack as a track is just plates fixed to the side plates of a chain.) was determined by stretching a string between the front top track roller over the track to the top of the front track idler.
The track tension was then adjust until there was a gap of 2-3 inches from the point where the track 'sagged' most. Track tension is ultimately important to prevent early wear. Same a on a bike.

More scientific procedures were looked at and implemented as designers got more say.
The technique was to adjust the track until it was tight/no slack. Mark a point on the frame. Mark a point a precise distance from the tight mark. Loosen the track past the set point and then adjust it back out to the set point.

No argument.

Why can bike manufacturers do this?

It is not really too much hassle for a bike chain really.
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

[yen_powell]

I have a bit of copper tube. If it fits snugly between the chain and swing arm at the scratched mark half way along all is well. If there is a gap or it won't fit adjust accordingly.

It's a shorter bit of tube for the Versys compared to my Africa twin which has to have a huge amount of slack on the chain.
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Blackmail is a nasty word........but not as nasty as phlegm!
XT1200Z and a DR350 in bits

[stinkwheel]

If you think this is bad, try going on a track cycle forum.

People can and do set a slight offset on the chainring bolts to compensate for slight ovality so the chain maintains an even tension all the way round.

In fairness, you could probably do it on a motorbike too. They set the tension at the tightest point then loosen the chainring bolts (closest thing would be the rear sprocket bolts on a motorbike) enough to allow it to move slightly but not enough so it is loose. They then give the top run of chain a sharp tap causing the ring to move on the bolts slightly, re-tighten and find the next tight spot and repeat until the minimum of tightspotness is achieved.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[jaffa90]

Just watch MOTO-GP when in slow motion and see them chains wagging up and down.

[Sweaty_Doughnut]

I will adjust the slack this weekend according to the manual. I am wondering, how a dealer can set it below the spec as there is a possibility to damage the bike?

[yen_powell]

[jaffa90]

[Sweaty_Doughnut]

[MCN]

[Sweaty_Doughnut]

[jaffa90]

Sorry, I missed your question. I tested with myself on the bike only and the slack is 10 millimetres at best[/quote]

So what was the slack off the bike and as said two up,??????????
Pot holes will give further travel of the swing arm which may tighten the chain.

[Sweaty_Doughnut]

[stevo123]

I think what the lads are saying is err on the slack side. It's not an exact science and is not a critial adjustment really.
Tight=Bad
As per spec=Perfect
Bit flappy=Fine

[MCN]

Do it once as per the manufacturer's guide/specification.
If happy slacked it all off and do it again.
Practice is what you need. 😊
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

[Hong Kong Phooey]

¿Qué?
Always do what manuel says:

https://static.independent.co.uk/s3fs-public/styles/story_large/public/thumbnails/image/2016/12/02/09/andrew-sachs.jpg

35mm innit?
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'81 CG125, '97 FZS600 : '99 CBR600F4, '09 KTM RC8