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Obvious??

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Ordering new chain/sprockets. If I go up 2 in the rear, I assume I need a 2 link longer chain??
 

bwdmax

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Yes you need a longer chain if you want to keep the rear wheel in the same place. I have two wheel sets for my KTM one with a 48T and one with 50T I just flip the blocks on the axle, this is why they are offset. This moves the rear wheel slightly forward.
 
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Yes you need a longer chain if you want to keep the rear wheel in the same place. I have two wheel sets for my KTM one with a 48T and one with 50T I just flip the blocks on the axle, this is why they are offset. This moves the rear wheel slightly forward.
not option on Honda.
 
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What bike ? I wouldn't think you need a longer chain for that .
CRF450, you don't think so? 2T on rear sprocket, seems to me the sprocket diameter is larger so need more chain? I'm dumb just ordered 2T bigger, if wrong I can cut some out easier than adding, lol.
 

bwdmax

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Like i said all depends if you want the rear wheel to stay in the same place. Some bikes don't seem to be affected by moving the wheel some do. For instance some will wheelie easier, good or bad...depends on your perspective. The closer the rear wheel is pulled in the quicker it will steer once again enough to tell the difference or care. Rear tire size and clearance at the front of the swing arm is a factor also.
 
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Like i said all depends if you want the rear wheel to stay in the same place. Some bikes don't seem to be affected by moving the wheel some do. For instance some will wheelie easier, good or bad...depends on your perspective. The closer the rear wheel is pulled in the quicker it will steer once again enough to tell the difference or care. Rear tire size and clearance at the front of the swing arm is a factor also.
Like to stay the same or close.
 

2WheelNut

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116 will work. Generally speaking, the wheel will be half a link more forward and you'll have to back off (screw in) the tensioners a bit.
 

Tourmeister

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I don't believe the number of links is strictly dependent on the number of teeth. I have changed sprockets on my 530 EXC while using the same chain. I just had to slightly change the rear axle location. It doesn't take much. The bike issue is whether the chain is long enough to go around the sprockets before the adjuster hits the stop in the forward position and it is not too tight.
 

2WheelNut

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I don't believe the number of links is strictly dependent on the number of teeth. I have changed sprockets on my 530 EXC while using the same chain. I just had to slightly change the rear axle location. It doesn't take much. The bike issue is whether the chain is long enough to go around the sprockets before the adjuster hits the stop in the forward position and it is not too tight.
If you think about it. + / - 2 links of chain takes the adjustment equivalent to the length of one link in the adjusters.

A chain link is less than an inch, adjusters usually have almost 2 inches of adjustability.

As such, you can often accommodate different size chain and sprocket combinations with the adjustment.

However...the adjustment is moving the wheel forward or back and it does change the geometry of the suspension, weight balance, and how the bike will handle on acceleration, braking, turning and jumping. It may or may not matter to many but a racer at a high level can definitely tell the difference and will want to keep the wheel in the same place by adjusting the chain length.
 
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Pro tip. Order a few more links than you need, then cut to fit. Afterwards you should have the coolest desk fidget toy in the office. This one has been on my desk for a long time and through a LOT of conference calls.

DSC00080-L.jpg
 

Tourmeister

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Pro tip. Order a few more links than you need, then cut to fit. Afterwards you should have the coolest desk fidget toy in the office. This one has been on my desk for a long time and through a LOT of conference calls.

View attachment 244369
How did you get it clean? The new chains I buy come all coated in thick grease... :wary:
 
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How did you get it clean? The new chains I buy come all coated in thick grease... :wary:
Kerosene I guess. This one is some 15 years old or so. Been a while, don't completely remember but I've always used kerosene to clean my chains so that's most likely.

I like this number of links because you can make a pyramid with it.

DSC00084_01-S.jpg
 
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Check my math. I think it is 1 extra link for two teeth.

Assuming that the chain leaves the gear at the halfway point, which is close but not exact, you get:

Chain length old = 2*L + (2*pi*r1)/2 + (2*pi*r2)/2

Where L is the distance between sprockets r1 is the radius of the front sprocket and r2 is the radius of the second sprocket. (2*pi*r) is the circumference of the sprocket, but the chain only travels half of the sprocket so (2*pi*r).

So if you add two teeth, to the sprocket the circumference is 2*pi*r+2x. where x is a link length.

My new equation with the new rear sprocket, keeping the sprocket adjuster in place (the length between the sprockets is constant) is then

Chain Length new = 2*L + (2*pi*r1)/2 + (2*pi*r2 + 2x)/2
Which is
Chain Length New = 2*L + (2*pi*r1)/2 + (2*pi*r2) + 2x/2

So Chain length New minus chain length old is 2x/2 = x = the length of 1 link. ??

Or intuitively, you can think of one tooth being added to the right of the sprocket, where the chain is, and one tooth being added to the left of the sprocked where the chain ain't...so the chain only has to get one tooth longer...

???
IMG_20191002_130938.jpg
 
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Seems like the 1 tooth on each and only one engaging is off to me. But I'm dumb and why I asked. But seems the diameter of the sprocket is larger than before.
 
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