Checked under my sprocket cover today... what is this?

[MFD]

So I finally got round to taking the sprocket cover off to check the nut today, and I've not seen a sprocket like this before.

[smg id=3108]

It looks like some kind of plastic or resin was moulded around the sprocket, going out so far that the remaining parts touch the chain side plates. What weirdness have I stumbled onto?

I've also got the old 9mm thick nut, which I've read should be upgraded to a 12mm thick one, but there's only ~1mm of thread exposed on  the end of the output shaft. Do I need to change more than just the nut and locktab?

Thanks

[bandit]

That's the original sprocket design or what's left of it the orange nylon is shock/noise damping (see here)


https://www.tapatalk.com/groups/fazerown...30268.html


I would replace sprocket & fit the new 12mm nut & locking washer,


http://www.wemoto.com/bikes/yamaha/fzs_6...t_kit_oem/


If you won't the same type sprocket with the damping,


https://www.ebay.co.uk/itm/Yamaha-FZS600...SwaWhZzr6B

[fazersharp]

Hears mine




And the 9mm nut

[fazersharp]

[MFD]

Thanks for the replies, that clears that mystery up.

bandit - Do you suggest replacing the sprocket just because the nylon has broken up? I see no reason not to do it at the same time, but if I change the front sprocket I'll be tempted to do the chain at the same time, then the rear sprocket too (both worn, but not enough that I'd normally replace them yet)...

As for nylon vs. plain steel sprocket, does the nylon ring make much of a difference? I'm guessing it only has an impact when switching between acceleration and overrun since the teeth would keep the chain loaded sideways the rest of the time?

[fazersharp]

I don't think the nylon being broken is a reason to replace but its odd that yours should of completely fallen off. Don't know if the plastic even makes any sound difference   

[limax2]

A drawing I did ages ago comparing the 9mm nut to the 12mm nut and their relationship to the gearbox shaft.
[smg id=1964]


Original sprocket on drawing is 8.5mm thick.

[Disorderlypunk]

is it just me that see's a  better compromise between the two ?
would a 12mm nut with a 3mm gap be even better?
ok that extra 1mm wont be on a thread but would reduce torsional stress/flex
yes i already know the reduction would be minimal but as tesco says 'every little helps'




great drawing by the way - great to see stuff like that when its not coming from a design aspect but more a 'what is there' aspect

[darrsi]

is it just me that see's a  better compromise between the two ?
would a 12mm nut with a 3mm gap be even better?
ok that extra 1mm wont be on a thread but would reduce torsional stress/flex
yes i already know the reduction would be minimal but as tesco says 'every little helps'




great drawing by the way - great to see stuff like that when its not coming from a design aspect but more a 'what is there' aspect

With threadlock it's just a case of "every little helps".
Not a definite cure, but most certainly an advantage to prevent a possible discrepancy.


It doesn't affect every bike, but for peace of mind it's worth doing.

[bandit]

Thanks for the replies, that clears that mystery up.

bandit - Do you suggest replacing the sprocket just because the nylon has broken up? I see no reason not to do it at the same time, but if I change the front sprocket I'll be tempted to do the chain at the same time, then the rear sprocket too (both worn, but not enough that I'd normally replace them yet)...

As for nylon vs. plain steel sprocket, does the nylon ring make much of a difference? I'm guessing it only has an impact when switching between acceleration and overrun since the teeth would keep the chain loaded sideways the rest of the time?

You can just replace the front sprocket on it's own no reason to do chain/rear sprocket at the same time, I would as you are going to fit a new locking washer/nut job done,but you could leave the old one on just make sure there are no nylon bits that are loose.


As for nylon or not nylon I don't know, have heard that with is quieter but looking at your pick of your sprocket you tell me.

[MFD]

Eh, ordered a new plain sprocket for the sake of £12, the nylon can't be doing much damping on mine anyway.

Stay tuned for it somehow rattling like a set of tracks.

[limax2]

I have just received a JT front sprocket from wemoto priced at £7.19 . Postage was £3.30 but that covered several other items as well.
I was surprised to find it had the sound damping stuff on it, although softer than on a genuine Yamaha sprocket. More like fairly hard rubber than the hard plastic feel of the original sprocket.
Also not a complete circle on one side and it appears to be bonded on rather than moulded through holes as the original.
[smg id=3113]


[smg id=3114]

[bandit]

Very interested to hear your opinion on this sprocket limax2, whether it is as good as the original one noise wise.

[Disorderlypunk]

fitting the locking washer is gonna be a bugger with that rubber sitting in the way

[fazersharp]

Very interested to hear your opinion on this sprocket limax2, whether it is as good as the original one noise wise.

I wonder how long the rubber would last until it has worn down a little and not doing anything - like the plastic one.
Has anyone had any experience in any other make of bike that has this sort of sprocket fitted, the 1st Fazer 600s also had a noise dampening plate on the inside of the sprocket cover - could it be that for whatever reason they deemed the FZS noisy in that area.

[fazersharp]

fitting the locking washer is gonna be a bugger with that rubber sitting in the way

If you look at the rubber ring and compare it with my picture its about the same size so the unbent washer should fit

[Disorderlypunk]

ooh it fitting wont be a problem - but you have to be able to get a screwdriver in to bend up the tabs - original looks like its tapered at about 45degs
the new one looks much steeper

[fazersharp]

ooh it fitting wont be a problem - but you have to be able to get a screwdriver in to bend up the tabs - original looks like its tapered at about 45degs
the new one looks much steeper

Ah I see. It may actually make it easier to get good leverage on that rubber sticking up

[tommyardin]

[quote author=bandit link=topic=23903.msg277309#msg277309 date=1522095381]
Very interested to hear your opinion on this sprocket limax2, whether it is as good as the original one noise wise.

I wonder how long the rubber would last until it has worn down a little and not doing anything - like the plastic one.
Has anyone had any experience in any other make of bike that has this sort of sprocket fitted, the 1st Fazer 600s also had a noise dampening plate on the inside of the sprocket cover - could it be that for whatever reason they deemed the FZS noisy in that area.
[/quote]


That is right Sharpie the later Fazers did not have that metal sound damping plate inside the sprocket cover the mounting posts are the for it and drilled but just not threaded for the mounting bolts

[limax2]

Very interested to hear your opinion on this sprocket limax2, whether it is as good as the original one noise wise.

I can’t say I’ve ever heard the chain while riding so yes it will be very interesting and a surprise if I notice any difference. I will be keeping an eye on that rubber stuff to see if it stays in place!