Weird sound gone after loosening the chain

[TonnyOnWheelz]

So a couple days ago everything was fine, till I noticed a weird clicking, crunching noise from the rear, not sure what it was but it was only present when sitting on the bike and pushing it around, I did clean and lubed the chain but it was still there.

Now I ordered a new chain and sprockets, but at the same time I went to the mechanic cause the chain was really tight, I told him to loosen it for me a little( I don’t have the tools to do it) and to my surprised, the sound is gone !?

Should I still replace the chain and sprockets ? No idea how old they are as I bought the motorcycle only 3-4 months ago , the chain does have some rust marks on it tho.

 

[Gary in NJ]

What is the condition of the teeth on the sprockets? That dictates whether the sprockets should be replaced. There is a spec to measure chain wear, check your chain for excessive wear to determine if it should be replaced.

Surface rust can be cleaned. Failed o-rings and rollers equal a failed chain.

How long was your chain “really tight”? Is the mechanic that you asked to loosen the chain the same that adjusted it too tightly? If it is, I suggest you find a new mechanic. If he can’t be trusted to properly adjust a chain, he shouldn’t be trusted to do anything.

 

[grahammarsden]

Run your finger between the teeth on the rear sprocket and see if you can feel a "lip" or a "hook" instead of a smooth curve. If it isn't smooth, you need to replace the chain and sprockets as a set.

You should have a tool set in a bag underneath the seat that is all you need to adjust the tension.

It's a simple job, there are videos online which explain how to do it. The slack should be between 45-55mm when it's on the side stand.

Also make sure that your chain is lubricated every 2-300 miles or, IMO better, get a Scotoiler that will do it automatically as you ride.

 

[TownsendsFJR1300]

If the chain is rusted, it's likely not been maintained. Too tight, again, not
maintained properly. I suspect you'll need chain and sprockets.

**MORE IMPORTANTLY, proper adjustment is necessary.**..

As you posted, the chain seems to be tight.
I suspect it's mechanic induced as the FZ has a VERY loose correctly adjusted chain, see below:



You can check this with no tools, just a ruler. 1/4" too tight from spec's will cause issues.
Check on the center stand, swing arm at full droop.

2" / 50mm's TOTAL up and down play is the target.
Rotate the rear wheel watching for the TIGHTEST SPOT on the chain (up and down play).
This is where you'll adjust the spec's to..

Above is with a good chain, preferably clean and lubricated.

All that info is also in your owners manual.

**Make sure your mechanic is aware of the chain adjustment for the FZ
or you'll be destroying the new chain, possibly damage the output shaft bearing
on the engine(major overhaul).**

If you need that manual, PM me as I have it as a PDF.
.

 

[grahammarsden]

BTW a quick and dirty check of the chain tension is to put your finger where it says "Drive Chain Slack" in that picture above and try to push it against the swingarm.

If it goes easily (or won't touch at all), it's respectively either too loose or too tight and you'll need to adjust it.

If you can just push it there, but you need to use effort to hold it in position, then the tension is ok.

 

[Saveliy]

Hello, you said that you have no tools to loosen chain, but actually the default under-seat tool kit has basic tools to do so. It has both big keys to loosen the axle nuts.
Only it would probably be very hard to tighten it back to 110 (forgot exact number!) N*m with those tools.

 

[grahammarsden]

Only it would probably be very hard to tighten it back to 110 (forgot exact number!) N*m with those tools.

The rear axle requires 120 Nm.

When I do mine, it's based on the following:

1) 120 Nm is the torque caused by a mass of 12kg at the end of a 1 metre bar (assuming gravity is 10 m/s^2)

12 x 10 x 1 = 120Nm

2) So, if the bar was 0.5 metres long, you'd need a mass of 24kg (12 / 0.5)

24 x 10 x 0.5 = 120Nm

3) The 32mm ring spanner with extension handle from the under seat tool kit is (IIRC) about 18cm long from the centre ie 0.18 of a metre

4) I weigh about 63 kg (undressed), and 12 / 0.18 = 66.66, so if I push down on the spanner with my full weight with clothes on, that's close enough to 120Nm:

64 x 10 x 0.18 = 115.2Nm

Hope this helps!