Chain, again

[noobie]

I have read and used search but still it has too many differing opinions so thought I would ask again.

Carbie bird with a 6mm shim

I saw a few variations on chain adjustment

I saw put it on the centre stand and measure 35-45mm of play

I saw another than said take it off the centre stand, have someone sit on it then adjust it to normal tolerance 25-35mm of play

I saw put it on the sidestand then adjust to normal tolerance 25-35mm of play

I iz purplexed

 

[ScottyUK]

That's because you need to adjust it so that it's the correct tension when YOU are riding it. No one else has set the chain tension for YOU hence why you get different numbers.

For me I had the chain adjusted whilst I was sitting on it. Once I had it all set I jumped off the bike, put it on the side stand and measured the chain sag. That's now my reference point and I can do it on my own.

FWIW for me on my bike with a 6mm shim, I set the chain so that as it's tightest there's 60mm from chain centre to the underside of the swing arm where the rubber runner ends.

It works for me ... in fact I adjusted it today. :-0)

 

[slim63]

As above :-0)

I set my chains for me & whatever else I am carrying EG being not very heavy myself adding the missus effectively doubles the weight carried so different chain adjustment is needed

 

[mikeyw64]

dunno what the figures are, I just adjust it and use the toe of my boot to check it in a few places (one place but after rotatng) then tighten up when I'm happy.

Regarding whether it should be different with a shim in , my take is that it should be the same figure whether you have a 6mm shim or not as the amount of movement will be the same, just the starting point will be different.


A 6mm shim does not increase the amount of travel experienced.

 

[ScottyUK]

I don't understand you saying "same figure" but "different starting point" ?

 

[mikeyw64]

I font understand you "same figure" but "different starting point" ?

The swingarm & chain still only move through the same degree of vertical movement regardless of whether you have a 6mm shim in or not as it does not increase the amount of travel.

The only difference is that relative to the bike the "starting point" is different therefore to my mind the chain slack/tension measurement should be the "same figure" as for the stock bike.

 

[CBRDEAN0]

A 6mm shim does not increase the amount of travel experienced.

Correct

BUT

As the swingarm does not pivot in the same place as the front sprocket the sprocket to sprocket distance will start shorter after fitting the shim but still get to max distance ( sprockets & swingarm in line ) during travel.

 

[mikeyw64]

Correct

BUT

As the swingarm does not pivot in the same place as the front sprocket the sprocket to sprocket distance will start shorter after fitting the shim but still get to max distance ( sprockets & swingarm in line ) during travel.

Drat @tu*


Good point , the question is though is that shorter distance greater than or less than the shortest distance if the measurment is taken with you on the bike which then takes us back to, should the measurement be taken with someone on or off the bike

 

[noobie]

It works for me ... in fact I adjusted it today. :-0)

Have you got a red Bird? Serious question, I saw a red bird two up at Harlow on its way upto the M11 roundabout during the week

 

[Centaur]

Drat @tu*


Good point , the question is though is that shorter distance greater than or less than the shortest distance if the measurment is taken with you on the bike which then takes us back to, should the measurement be taken with someone on or off the bike

As the bike is ridden with someone on it then it makes sense to me to measure the slack with the usual weight on. I have always got someone about the same weight as myself to sit on and looked for two fingers width of slack in the middle of the bottom half of the chain. :-0)

 

[ScottyUK]

Have you got a red Bird? Serious question, I saw a red bird two up at Harlow on its way upto the M11 roundabout during the week

Mine is "Iron Nail Silver" ... or grey if we go with the majority vote 8rfl@

Wasn't out riding at all this weekend. A birthday and an anniversary has kept me grounded.

 

[noobie]

I might ask for your help with this chain thing seeing as your local

 

[Centaur]

I might ask for your help with this chain thing seeing as your local

Scotty does not own the "local", Noobie so "you're" is what you are after! Just saying! He does own the help though. 8rfl@

 

[CBRDEAN0]

Drat @tu*


Good point , the question is though is that shorter distance greater than or less than the shortest distance if the measurment is taken with you on the bike which then takes us back to, should the measurement be taken with someone on or off the bike

Did mine with the bike weighted.

Then checked what it was on the ctr stand for future ref and ease of setting

 

[slim63]

The swingarm & chain still only move through the same degree of vertical movement regardless of whether you have a 6mm shim in or not as it does not increase the amount of travel.

The only difference is that relative to the bike the "starting point" is different therefore to my mind the chain slack/tension measurement should be the "same figure" as for the stock bike.

Now then, bare with me a moment :-0)

The wheel moves up & down in an arc with suspension movement, this shape )
The tightest the chain will ever be is in the middle of the arc so if you have a shim fitted that effectively pushes the arm down & set the chain at that its possible that the chain will be very tight when the wheel comes back up to closer to the central position for example when hitting a big bump or carrying kit

Sorry to be pedantic but I have seen it & dealt with the consequences of over tight chains many times This is why I said above set the chain for yourself & the weight carried ;-0))