Chain adjustment after lowering

[CFB 4,601]

Having lowered the X so that Cath can get her feet down, a thought occurred to me.

Yes, it did hurt. 🙄

My thinking is that the chain should be adjusted to provide the same slack as before it was lowered, as the suspension travel is the same, it is just the axle is nearer the seat.

Right or wrong?

[Tex 36,816]

I agree. The chain should be re-adjusted to give the same amount of free play that it always had. With the weight of the bike on the wheels I imagine there’s less slack on the chain now? Which would indicate it would be too tight on ‘full bump’. 

[CFB 4,601]

Yup, less slack, which made me think about it. 

Spanners out then. Thanks Simon. 

[PoppetM 16,828]

Was thinking of Tigger today  it is nice to hear Cath will be,asking us of the X. 

Oh chains...remind me...what are those things again..?

[Spindizzy 7,109]

3 hours ago, Tex said:

I agree. The chain should be re-adjusted to give the same amount of free play that it always had. With the weight of the bike on the wheels I imagine there’s less slack on the chain now? Which would indicate it would be too tight on ‘full bump’. 

 

Fractionally less probably. Chain tightens slightly as the suspension compresses, tightest when everything is in a straight line.

 

I would tension it to the tighter side of standard as on a non lowered bike it would still slacken a fraction as the swingarm would move lower.

 

Its probably marginal, as long as its not slapping the underside of the swing arm its probably fine.

 

 

[Tex 36,816]

 

1 hour ago, PoppetM said:

Oh chains...remind me...what are those things again..?

 

They were a genuine advancement over their predecessor (the leather belt!) but that was about a hundred years ago. When fully enclosed in an oil bath they’re an excellent way of transmitting drive but, with only a couple of exceptions that spring to mind, the enclosures were dropped about fifty years back. Run naked and sprayed with rain water and road filth they’re just a labour intensive, hideous anachronism. I hope to God my current bike is the last chain driven one I own.  

 

But apart from that, chains are fine!  

[Rocker66 34,373]

Just been reading about a 1938  brought Golden Dream which had shaft drive and a four cylinder boxer engine with the cylinders each side mounted one above the other. It was shown at the 1938 show but apparently never went into production. It’s certainly a bike I had never heard of.

[Tex 36,816]

Rock, they have a Golden Dream in the National Motorcycle Museum at Solihull. Lovely looking thing, must have been a sensation in 1935! Best way I can describe it (I’ll try and dig out some pics) is like a first model GL1000 but ‘not quite’..  

[Spindizzy 7,109]

9 minutes ago, Tex said:

Rock, they have a Golden Dream in the National Motorcycle Museum at Solihull. Lovely looking thing, must have been a sensation in 1935! Best way I can describe it (I’ll try and dig out some pics) is like a first model GL1000 but ‘not quite’..  

 

[Rocker66 34,373]

The one in the magazine is actually gold in colour. It’s quite a large article on it. The magazine is the February issue of Classic Bile Guide.

[sad vampire 109]

After lowering my NC750X DCT 30mm I had a friend watch the suspension & chain whilst I bounced all my weight on the saddle to see if adjustments were necessary.

 

Chain did need a slight adjustment.

 

Rear shock needed to be harder by 1 notch (it was on "2" & it needed "3" to stop the suspension bottoming so easily.

 

 

[SteveThackery 3,090]

6 hours ago, Spindizzy said:

 

Fractionally less probably. Chain tightens slightly as the suspension compresses, tightest when everything is in a straight line.

 

 

Is that definitely true - that the swing arm on a bike is always "below" the centre line in its steady-state position?  Obviously the chain is tightest when everything is in a straight line, but is that always at or towards full bump on every bike?

[Spindizzy 7,109]

6 hours ago, SteveThackery said:

 

Is that definitely true - that the swing arm on a bike is always "below" the centre line in its steady-state position?  Obviously the chain is tightest when everything is in a straight line, but is that always at or towards full bump on every bike?

I don’t know about every bike.  But if you know where the drive sprocket sits and the swing arm pivot point imagine a line through both and that’s either above or below the rear axle bolt. Likely above for most off road style and mx bikes due to the travel required.  

[embee 7,288]

Straight line is usually at about mid travel of the suspension, this is so that the total variation is minimised (loose/tight/loose as it compresses).

If you lower the bike with suspension links the setting at rest will be slightly less slack than for the stock arrangement, it will be sitting nearer to the straight line position. Best way to be sure (and what  always do on any chain bike I have) is have the bike on a centrestand, disconnect the linkage, and raise the rear wheel with blocks until the chain is at its tightest. Adjust the chain to give a hint of slack at this point. Reconnect linkage and then see what you get with the suspension extended, either on the centrestand or sidestand, however you want to check it in future.

[Guest Skid]

On ‎26‎/‎01‎/‎2019 at 16:05, Grumpy Meltdown said:

Yup, less slack, which made me think about it. 

Spanners out then. Thanks Simon. 

I'll sort it when I'm round Mr B.....and check it while I ride it home & back if we don't get my gadgets fitted in the time we have to fit them 

[Morph 257]

I’ve  never understood why the chain isn't inside a (fairly basic) cover. I mean the top sort of is... why not just provide a simple (plastic even) snap cover. No external road grime. Oil and grease fling contained therein etc. Snap off to clean and regrease

[Spindizzy 7,109]

22 minutes ago, Morph said:

I’ve  never understood why the chain isn't inside a (fairly basic) cover. I mean the top sort of is... why not just provide a simple (plastic even) snap cover. No external road grime. Oil and grease fling contained therein etc. Snap off to clean and regrease

Because it doesn't look cool. 

Other than that its always been a good idea. They even took it away from the Honda 125's.The early CG125 had it and was ideal, but then it dropped away when image became more important.