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Hi guys,

The G310R is my first bike and I've been reading as much as possible about motorcycle maintenance, but one thing I'm unsure of is how to properly measure chain sag.

I watched a video on Revzilla about it that was insanely helpful, but was hoping someone with a G310 could coach me on the process. I was looking at my chain last night and it looks rather "saggy", I would estimate nearly 3.5" of sag.

My bike is nearing 700 miles, so I intend to clean and lubricate the chain and want to set its sag correctly while I'm down there.

Thanks!
 

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There's a sticker on the swingarm, at this location, push the chain up, that's your zero reading and then pull the chain down, that's your chain sag reading as per the manual it should be 4-5cm. Mine is pretty close to 5cm, haven't needed to adjust it yet, it was adjusted at my first service, but will probably need to adjust it soon.
 

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I had to adjust mine the day I brought it home.
It was tight as a drum. And my tires were over inflated by 15 psi front and rear.
At 200 kms, I had to tighten the chain as she was getting a bit too loose.
I am a nut bar on chain tension, cleaning and lubing.
 

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Porth,

My chain hits the swing arm/rail when I push it up and there is still a little slack in it for it to go further if that piece wasn't there.

So I should place my measuring tape at the center of the sticker on the swing arm? Should the bike be unloaded and in neutral? When I park the bike in 1st gear, the chain will tighten up.

Tickster,

my rear tire was at 55 psi when I got it, but the front was smack on.
 

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Porth,

My chain hits the swing arm/rail when I push it up and there is still a little slack in it for it to go further if that piece wasn't there.

So I should place my measuring tape at the center of the sticker on the swing arm? Should the bike be unloaded and in neutral? When I park the bike in 1st gear, the chain will tighten up.
If you see the chain would likely go further when it touches the swingarm then it is likely to exceed the prescribed 4-5cm clearance.
Should be in neutral.
As per procedure in the manual, "Motorcycle with no weight applied, supported on its side stand".
Also before doing do, you should check the current tension on the whole length of the chain by rotating the wheel and pushing the chain (rear stand is a must here). Chains do not always stretch equally so you need to find the tightest spot before you perform the adjustment. Not doing do might result in a chain too tight when it reaches the said point. This is also written in the manual BTW.
 

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Porth,


So I should place my measuring tape at the center of the sticker on the swing arm? Should the bike be unloaded and in neutral? When I park the bike in 1st gear, the chain will tighten up.

Measure the max deflection of the chain ie push down and measure, push up and measure, the difference is the figure you are looking for. It doesn't matter where you measure from as long as you are consistent, use the ground if you like. Do this with bike in neutral. ,
BTW it sounds like your chain is incredibly loose, if so it needs attention soon. I wonder how a chain could get so loose on a low mileage bike.
 

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wmrcs, when you loosen your rear wheel bolts to tighten up the chain, be diligent to have both sides of the adjustment marks even.
Make sure to torque the bolts as per spec and check again after you have ridden it a bit. Rear wheel alignment is fairly important for
tire, and driveline wear.
 

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do you guys use a torque wrench when adjusting the chain slack? if so, how you fasten the bolts at the adjustment mark (an open-end wrench is needed)? the only suitable tool i managed to find, costs about 170 euros or ~150 $(it's the cheapest yet decent Taiwan-made wrench).
 

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do you guys use a torque wrench when adjusting the chain slack? if so, how you fasten the bolts at the adjustment mark (an open-end wrench is needed)? the only suitable tool i managed to find, costs about 170 euros or ~150 $(it's the cheapest yet decent Taiwan-made wrench).
Always use a torque wrench, if your doing your own work it's a must have tool.
Little locking nut is 19NM or about 14 ft lbs. Large axle nut is 100NM or about 74 ft lbs.
Check your riders manual it's all there.
You can always just try it without a torque wrench, BUT, you can damaged threads, warp metals, or just end up with
loose bolts at the worse times.
Maybe there is a garage near that you could stop by and take the 2 minutes to borrow one and do it right.
 

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do you guys use a torque wrench when adjusting the chain slack? if so, how you fasten the bolts at the adjustment mark (an open-end wrench is needed)? the only suitable tool i managed to find, costs about 170 euros or ~150 $(it's the cheapest yet decent Taiwan-made wrench).
You should be able to find a decent torque wrench for about 1/3 of that cost, search ebay for a 7-112nm torque wrench.
 

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i found many torque wrenches at about 50 euros (~45$) BUT none of them could use open ended bits.most of them work only as socket wrenches.
Open ended bits like this are known as Crows Foot spanners - you should be able to get individual bits (or sets) with the appropriate size square drive from a good tool supplier.
Crows Foot spanners can be standard open end or semi-ring as images below
 

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This is getting a little intense. A few comments.

As you have noted, unladen bike on side stand (per the manual).

Chain slack shouldn't change if parking the bike in gear, but it will be easier to adjust properly if it's in neutral.

Get a tape measure that you can lock open and set it on the ground with the tape pointing up (this frees your hands to do other things).

Note the reading on the tape with the chain fully sagged, and push the chain up until it is snug. If you start to life the bike of the side stand, you're pushing too hard.

Note that reading and do the math.

If the chain is too loose, adjust it so that it is close to the minimum number - if in doubt, err on the loose side.

Snug the locknuts on the adjusters with one wrench while holding the adjustment bolt with another. While BMW specifies a torque setting for this (bless their little hearts) it isn't a critical setting. Snug works.

Tighten the axle nut with a torque wrench - this IS a critical setting. You will need a 1/2 inch drive wrench to achieve the necessary torque (74 lb/ft or 100 Nm).

In the spirit of full disclosure, I use a torque wrench for any fastener that I have a spec for. The chain adjuster locknut is just about the only exception. I've never had one loosen in over 50 years of riding. I will now end this and make room for the 85 people who have.
 

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In the spirit of full disclosure, I use a torque wrench for any fastener that I have a spec for. The chain adjuster locknut is just about the only exception. I've never had one loosen in over 50 years of riding. I will now end this and make room for the 85 people who have.
what kind of torque wrench you use? i mean a cheap one will do or you use a high end brand like Facom ?
 

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what kind of torque wrench you use? i mean a cheap one will do or you use a high end brand like Facom ?
This is just a motorbike, not a race car or rocket ship.
Use a cheap one and get it done.:D
 

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You'll need a 27mm socket or crowfoot spanner for the axle nut, and a 13mm crowfoot spanner for the locknut.


I got a 3/8 drive torque wrench 7-112nm, a 27mm hex socket with 3/8 drive, and a 13mm crowfoot spanner with 3/8 drive.


the 27mm crowfoot spanners only seem to come in 1/2 drive
 

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what kind of torque wrench you use? i mean a cheap one will do or you use a high end brand like Facom ?
My torque wrench is not a cheapie, but reasonable quality... but nowhere near as nice as Facom, or Stahlwille, which I'd love to own but really can't justify spending the money on when (realistically) there's nothing wrong with the one I do have.

I'd also make the comment that the only time I'd use a crows foot is on something that I was unable fit a regular socket on to due to lack of space or similar.

Another point is that using a crows foot in a torque wrench can result in higher torque being applied due to the extension of the crows foot. There are ways to calculate what the setting needs to be (I found an online calculator here Torque Wrench Adapter Calculator - CNCexpo.com), but if you position the crows foot so it is 90° to the torque wrench handle, the difference in setting is pretty well insignificant and so can be set the same as specified.
 

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This is just a motorbike, not a race car or rocket ship.
Use a cheap one and get it done.:D
i don't disagree with you, it's not a rocket. i was planning to buy a cheap torque wrench (about 50 euros), but when i did a bit of research, i found out that the cheap ones tend to be faulty (their calibration is not correct).that's why i am asking so many questions, after all a torque wrench is a valuable tool (when it works properly) :wink2:
 

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i don't disagree with you, it's not a rocket. i was planning to buy a cheap torque wrench (about 50 euros), but when i did a bit of research, i found out that the cheap ones tend to be faulty (their calibration is not correct).that's why i am asking so many questions, after all a torque wrench is a valuable tool (when it works properly) :wink2:
If you know somebody with a top quality torque wrench you can always check a cheaper torque wrench by "letting the two wrenches torque to each other" sorry, dad joke, but this is how you can check a torque wrench against a calibrated one, by joining the drives together and seeing which one gives in first.
 

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i don't disagree with you, it's not a rocket. i was planning to buy a cheap torque wrench (about 50 euros), but when i did a bit of research, i found out that the cheap ones tend to be faulty (their calibration is not correct).that's why i am asking so many questions, after all a torque wrench is a valuable tool (when it works properly) :wink2:
Well I have two fairly inexpensive torque wrenches, one in ftlbs., the other in inch/lbs. Never had an issue.
Maybe they are off by a a few lbs one way or another, but all has been good. Just remember to reset to zero after
using. I have used our super expensive ones from work on my vehicle wheels, and when rechecking the torque at home
after a 100km or so, my wrenches seem to be on par with the expensive shop ones. Which by the way are recalibrated
yearly.
 
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