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I'm going to attempt to tighten the chain tonight. In your guys' opinions, how many turns on the locknut should I start off with, to tighten the chain about a 1/2" (13mm)? I don't want to overtighten, but I'm quite novice to how many turns each swingarm nut will need to make the chain a 1/2" tighter.

Also, should I test the chain slack with me sitting on the bike? Or it it okay for the bike to be on it's side stand or have the rear lifted to check the slack? The slack was at about 38mm with the bike on its side stand.
Its supposed to be done with the bike on the side stand. Dont worry about how many turns etc, just rest your ruler on the swing arm in a vertical position and tighten the nuts equally until you are getting 1- 1.25 inches of movement/slack when you pull the chain up and down with your hand.

After a while you dont even need to measure it, you just grab the chain and flop it up and down at the middle point on the swing arm and you will know whether its too tight or loose.
 

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I'm going to attempt to tighten the chain tonight. In your guys' opinions, how many turns on the locknut should I start off with, to tighten the chain about a 1/2" (13mm)? I don't want to overtighten, but I'm quite novice to how many turns each swingarm nut will need to make the chain a 1/2" tighter.
After loosening the axle nut, use a couple box end wrenches to loosen the jam nuts on both of the axle adjusters.

Next thing I do is use a tape measure to compare the distance between the swing arm pivot and the axle on each side... the measurement should be the same on both sides of the swing arm. If not, tighten the adjuster nut on the side with the shorter measurement, until they are the same side to side.

Then turn the adjustment nuts 1/4 turn at a time on each side and recheck the chain free play. Also make sure the axle adjusters and the end plates are seated on the ends of the swing arm while making adjustments.

Also, should I test the chain slack with me sitting on the bike? Or it it okay for the bike to be on it's side stand or have the rear lifted to check the slack? The slack was at about 38mm with the bike on its side stand.
No extra weight on the bike. It can be either on the side stand, or on a rear wheel paddock stand. I prefer a paddock stand... it makes the job a lot easier, as you can freely rotate the wheel while checking the chain free play at multiple points.
 

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Thanks MotoMike. It sounds simple enough. Hopefully I don't strip the locknuts, I've heard of that happening.
I tend to think that in those instances where people have stripped the threads on the adjuster bolt, they were probably trying to turn the jam nut in the wrong direction by mistake... it happens. Whenever I read accounts of stripped bolts & nuts on the forums, I have to remind myself that many of the new first time owners of these bikes are learning to 'turn wrenches' for the first time.

Just remember to use two box end wrenches, and hold the wrench on the larger adjustment nut stationary while turning the wrench on the smaller jam nut in the opposite direction (counter clockwise) to loosen... open end wrenches can slip and round off the flats on the jam nuts.
 

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Sounds good. This will be my first time with adjusting a chain (my R6 was always serviced through the dealer). I've been doing maintenance now on all my vehicles for the last few years. I sometimes second guess myself with things that are simple like adjusting a chain, thinking something catastrophic will happen lol
 

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It's not as easy as you might think. The left adjusting nut tightens the chain, but the right one then loosens it as you turn the nuts both clockwise. In other words, if you start with the left nut, you need to over-tighten the chain slightly so that as you then turn the R nut clockwise, it will loosen the chain slightly. There is some art to adjusting chains. Also the wheel can move after you have everything the way you want and begin to tighten down the axle nut leaving you with a gap usually on the right side swing arm and thus a chain that is out of alignment. I've been doing this for years and I still have issues with it on occasion. I don't recall the CB300F giving me trouble, but other bikes like the Yamaha FZ-07 sure did.
 

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No extra weight on the bike. It can be either on the side stand, or on a rear wheel paddock stand. I prefer a paddock stand... it makes the job a lot easier, as you can freely rotate the wheel while checking the chain free play at multiple points.
Ive been doing mine on the side stand, wasn't sure you could use a paddock stand, I will do it that way next time, so much easier.

Mark
 

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I have a few questions because I found myself not having ALL the tools necessary to complete the job. I just want to confirm dimensions.

1. What size is main axle nut?
2. What size is the adjacent axle nut? (19mm?)
3. What size are the adjusting bolts? (12mm?)
4. What size are the locking nuts? (8mm?)
 

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10mm and 12 mm for the adjusting and set nuts. The rear axle bolt is 24 mm. The left side is attached to the axle and doesn't unscrew, but it could rotate as you loosen the axle nut. If so, a 19 mm socket will hold it. You may need a long handle or breaker bar to loosen the axle nut and should have a torque wrench to tighten it back to specs.
 

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So I brought the bike to the dealer, for $15 and 20 minutes, they tightened the chain to what looks to be about 22-24mm when I checked 3 different points. Not too bad. In the meantime, I am going to pick up all the tools needed for it so I can do it down the road.
 

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So I brought the bike to the dealer, for $15 and 20 minutes, they tightened the chain to what looks to be about 22-24mm when I checked 3 different points. Not too bad. In the meantime, I am going to pick up all the tools needed for it so I can do it down the road.
You can get away with using the tools in the tool kit for loosening and tightening the rear axle nut if you don't want to invest in 19 & 24mm spanners. You slide that sleeve over the end of the 24mm ring spanner handle to give yourself more leverage. Position the spanner in the horizontal position and use your foot pushing downwards to get a good amount of force to undo the nut.

But definitely get quality ring/open end type 12 & 14mm spanners or you may end up with rounded nuts. Always use the ring end of the spanner on the 12mm locking nut to prevent spanner slippage and rounding off.

Personally I've never used a torque wrench on a rear axle nut and haven't had any dramas with a loose nut in 35 years of riding. They aren't cheap!
 

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You can get away with using the tools in the tool kit for loosening and tightening the rear axle nut if you don't want to invest in 19 & 24mm spanners. You slide that sleeve over the end of the 24mm ring spanner handle to give yourself more leverage. Position the spanner in the horizontal position and use your foot pushing downwards to get a good amount of force to undo the nut.

But definitely get quality ring/open end type 12 & 14mm spanners or you may end up with rounded nuts. Always use the ring end of the spanner on the 12mm locking nut to prevent spanner slippage and rounding off.

Personally I've never used a torque wrench on a rear axle nut and haven't had any dramas with a loose nut in 35 years of riding. They aren't cheap!
My bike didn't come with a tool kit? It only came with a hex and wire strap. Was it supposed to come with a tool kit?
 

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My bike didn't come with a tool kit? It only came with a hex and wire strap. Was it supposed to come with a tool kit?
I would say yes. Contact your dealer.
Where would it be located?? Under the rear seat?
These bikes imported to the U.S. don't come with the full tool kit as they do in most other markets. Unfortunately, we only get a hex key. The wire cable is intended to be used with the helmet holder/lock.
 
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Thanks for clarifying that MotoMike. That's unfortunate though, now I'll have to buy the tools. Do you think it would be okay to just get some metric 6-point combo wrenches to do the job? 12,14,19,24MM
 

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10mm and 12 mm for the adjusting and set nuts. The rear axle bolt is 24 mm. The left side is attached to the axle and doesn't unscrew, but it could rotate as you loosen the axle nut. If so, a 19 mm socket will hold it. You may need a long handle or breaker bar to loosen the axle nut and should have a torque wrench to tighten it back to specs.
10mm/12mm? Or is it 12mm/14mm?
 
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