Chain tension

[Grumpy old man 4,682]

Newbie Alert 

Hi all

How tight should the chain be when both sprockets are in line ( chain at its tightest point).

 

Thanks

 

[PoppetM 16,847]

1 hour ago, Grumpy old man said:

Newbie Alert 

Hi all

How tight should the chain be when both sprockets are in line ( chain at its tightest point).

 

Thanks

 

From my memory I want to say 30mm. Ny NC had a sticker on the swing arm, spent a lot of time staring at it while Trisaki tried to teach me alignment and chain tension, I am sure it said 30...

 

[MikeBike 5,006]

Manual: Drive chain slack:
30 to 40 mm (1.2 to 1.6 in) on side stand level surface

 

Edited February 16, 2021 by MikeBike

[Grumpy old man 4,682]

41 minutes ago, PoppetM said:

From my memory I want to say 30mm. Ny NC had a sticker on the swing arm, spent a lot of time staring at it while Trisaki tried to teach me alignment and chain tension, I am sure it said 30...

 

 

Just now, MikeBike said:

Manual: Drive chain slack:
30 to 40 mm (1.2 to 1.6 in)

Thank you both but you have both failed because you didn't read the question properly,  chain at its TIGHTEST point when the sprockets are in line so wheel at it's furthest point from the drive sprocket. Go on try again.

[MikeBike 5,006]

I did read the question but that's the only reference I had so added the "on side stand level surface" to clarify.

 

[PoppetM 16,847]

23 minutes ago, Grumpy old man said:

 

Thank you both but you have both failed because you didn't read the question properly,  chain at its TIGHTEST point when the sprockets are in line so wheel at it's furthest point from the drive sprocket. Go on try again.

Sorry, I only know how much slack there should be, I have killed enough chains with that slack not to need to worry about where the tightest point is  

[Andy m 23,567]

FFS we'll have the lasers and spring loaded monkey weight things out next out next 😣 😁🙈🙉🙊😁

 

1. Chain should move towards swing arm before toe cap is pressed against your socks. Use the same boots each time for accuracy. 

2. Open throttle should produce acceleration not a slappy-bangy-thrashy sound. 

3. If in doubt loosen until boot test results in getting oil on the swing arm. 

4.Stop fiddling or it'll fall off

 

Andy

[Grumpy old man 4,682]

9 minutes ago, Andy m said:

FFS we'll have the lasers and spring loaded monkey weight things out next out next 😣 😁🙈🙉🙊😁

 

1. Chain should move towards swing arm before toe cap is pressed against your socks. Use the same boots each time for accuracy. 

2. Open throttle should produce acceleration not a slappy-bangy-thrashy sound. 

3. If in doubt loosen until boot test results in getting oil on the swing arm. 

4.Stop fiddling or it'll fall off

 

Andy

Oh well that's helpful.

The reason I ask is, the suspension on the crf has been slightly altered so when on its side stand ( the position for checking chain slack) there is no movement  on the suspension so if I adjust the chain at the correct tension 25-35mm then it's really tight at full swing so I just wanted to know how tight should it be guitar tight or just enough wiggle room.

Edited February 16, 2021 by Grumpy old man

[Andy m 23,567]

Honestly, stop faffing. 

 

If it moves the thickness of a finger or touches the swing arm all round its fine. 

 

Edit to add- Don't worry about numbers, 25mm or 42mm, not guitar string tight is not guitar string tight. 

 

Andy

Edited February 16, 2021 by Andy m
more detail

[PoppetM 16,847]

And I thought my husband had reached a new height of boredom. Apparently he has removed 120 wall plugs from the garage wall and filled them in....

[outrunner 4,457]

Lloyd, prop the bike in an upright position and put a rachet strap under the swingarm and over the bike, tighten said rachet strap until the sprocket centres line up and there is the your answer.

 

 

Andy.

[Grumpy old man 4,682]

9 minutes ago, outrunner said:

Lloyd, prop the bike in an upright position and put a rachet strap under the swingarm and over the bike, tighten said rachet strap until the sprocket centres line up and there is the your answer.

 

 

Andy.

Hi Andy, Yep that's exactly what I've done but I was just thinking at that point how tight should the chain be. Think I've got it sorted now. Thanks.

Hope you're keeping safe. Do think Derbyshire will be a goer this year?

[outrunner 4,457]

15 hours ago, Grumpy old man said:

Hi Andy, Yep that's exactly what I've done but I was just thinking at that point how tight should the chain be. Think I've got it sorted now. Thanks.

Hope you're keeping safe. Do think Derbyshire will be a goer this year?

As long as you have a few mm of slack when the sprockets are in line I am sure it will be fine. All good here Lloyd, thanks for asking but at the moment not too sure about Derbyshire.

 

Andy.

[jeremyr62 2,561]

Good video on chain wear and the origin of tight sports.

 

[Andy m 23,567]

He doesn't exactly come to a conclusion does he 😁😁😁

 

He also seems to assume the chain plates are repeatable and sat in the same spot on the sprocket unless he's managed to get the DTI pointer on a sprocket tooth. A rubber belt he'd be more certain on which is where the technique is from. A change in tooth profile, roller diameter, something between roller and sprocket could all produce the same result? The tip of the tooth isn't where the chain roller sits. 

 

Makes the point that changing the chain and leaving the sprockets is a bit pointless but otherwise he just seems to think using a DTI must make a better job of it. 

 

Andy

[jeremyr62 2,561]

He's making some assumptions but I found it a reasonable demonstration that the tight spots arise from non uniform wear in the sprocket moving it out of round. Not much you can do about it once you have it. I suppose you could argue it makes more sense to change sprockets but leave the chain alone.

 

[Grumpy old man 4,682]

In the old days I'd sit on the bike, lean over wiggle the chain and think alls good. What have I become, I lie on the wet ground with a ruler now and count the millimetres spin the chain and try again, I use a digital Verniar gauge to measure wheel alignment.

[Hickky 3,131]

2 minutes ago, Grumpy old man said:

 

In the old days I'd sit on the bike, lean over wiggle the chain and think alls good. What have I become, I lie on the wet ground with a ruler now and count the millimetres spin the chain and try again, I use a digital Verniar gauge to measure wheel alignment.

 

Lloyd, just how far is your finger up your rect*m? Just go out and ride the thing, remembering a chain that is too tight fails much earlier than one that is slack. Your old wiggle method served me well for 87,000 miles on my Honda CX500, never had a chain failure!

[Spindizzy 7,109]

What is all this. Provided the chain isn't like a guitar string and just falls short of slapping the swing arm, its fine.

 

 

[listener 11,197]

55 minutes ago, Grumpy old man said:

In the old days I'd sit on the bike, lean over wiggle the chain and think alls good. What have I become, I lie on the wet ground with a ruler now and count the millimetres spin the chain and try again, I use a digital Verniar gauge to measure wheel alignment.

 

Amateur! 

 

You need a thermometer and manometer to compensate for air temperature and pressure surely? 

[Grumpy old man 4,682]

22 minutes ago, listener said:

 

Amateur! 

 

You need a thermometer and manometer to compensate for air temperature and pressure surely? 

Oh bugger off! 

[Andy m 23,567]

16 minutes ago, listener said:

 

Amateur! 

 

You need a thermometer and manometer to compensate for air temperature and pressure surely? 

Google.

 

If Google says it's colder than minus 2 stay in, leave the chain alone, drink tea. If you are going to ride at minus 2, just ride, the extra socks stop the toe-cap test working anyway.

 

I have the manometer, it's on the compressor I use to gun off the axle nut the first time after Honda.

 

The video Jeremy posted is actually the sensible one. If you let it play on the next bloke starts off with a diatratribe about sapping power (I have 47 HP, I'd notice if more than 3 escaped) and having a leg taken off (go on then , name two people it happened to). The one after wants to draw pictures of chain rollers as a fifteen minute lecture where showing a piece of old chain you can flex further sideways would take 10 seconds. Then it gets to Mr Lazer monkeys light show.

 

Andy

(Buggering off  )

[MatBin 5,094]

3 hours ago, Hickky said:

Lloyd, just how far is your finger up your rect*m? Just go out and ride the thing, remembering a chain that is too tight fails much earlier than one that is slack. Your old wiggle method served me well for 87,000 miles on my Honda CX500, never had a chain failure!

Your drive chain should have lasted much longer on a CX did you not use a ScottOiler?

[Grumpy old man 4,682]

45 minutes ago, MatBin said:

Your drive chain should have lasted much longer on a CX did you not use a ScottOiler?

Well blow me I've just cottoned on the CX500 was a shaft drive, naughty boys

[Defender 3,837]

On 18/02/2021 at 16:19, listener said:

 

Amateur! 

 

You need a thermometer and manometer to compensate for air temperature and pressure surely? 

You forgot the altimeter and inclinometer!