Changing Sprocket Nut....any special steps

[anutz]

Hi All,

So I have now got my engine back together, i.e. cylinder head on...and am working on the rest of the bike

I am changing the sprocket nut, I soaked it in Plusgas for the past week whilst I have been working on the cams, and with a 600mm breaker and a 32mm socket it came off with little effort

I made sure to have the transmission in neutral and someone applying the back brake

Is there any special process or is it just a case of lock tab on, screw and torque new nut then bend the tabs over fully?

I am using part numbers

90215-21290
90179-18006

The 12mm nut and lock tab

I have read parts of the Bulletin to dealers and it did mention to measure the thread depth?

[Jules-C]

It was the diameter of the thread that was to be measured but if the original but lasted all this time it's ok more likely than not.

The new thicker but has a slightly higher torque setting, should be plenty topics on here that will confirm what it is.

[Dave48]

It was the diameter of the thread that was to be measured but if the original but lasted all this time it's ok more likely than not.

The new thicker but has a slightly higher torque setting, should be plenty topics on here that will confirm what it is.

Suggest you go with 80 nM torque

[limax2]

Add a bit Locktite Nut Lock or similar compound to the clean thread as an added precaution. As recommended by Yamaha.

[darrsi]

Mine was torqued to 80Nm.

[unfazed]

The Yamaha recommended torque for the new 12mm nut is 90Nm

[darrsi]

The Yamaha recommended torque for the new 12mm nut is 90Nm

I knew that, I just didn't trust it after all the thread problems.

[Paulfzs]

id rather it fell off than destroying the thread and having to change the output shaft.

[anutz]

Thanks all, I think I will use some LocT and torque to 80Nm initially...

Is there any special way to secure the lock washer or do you just complete the bend that is started on 2 sides?

[Dave48]

Thanks all, I think I will use some LocT and torque to 80Nm initially...

Is there any special way to secure the lock washer or do you just complete the bend that is started on 2 sides?

Just tighten the nut & then bend the 2 tabs up against the side faces of the nut.

[fazersharp]

Hee is some more stuff just in case you have not found it yet http://foc-u.co.uk/index.php/topic,14924.msg169018.html#msg169018

And tourque wrench here for that nut http://foc-u.co.uk/index.php/topic,11878.msg132361.html#msg132361

And about that orange plastic thing here http://foc-u.co.uk/index.php/topic,11519.msg124002.html#msg124002

All about the crank case cover here http://foc-u.co.uk/index.php/topic,10124.msg105271.html#msg105271
Whilst you are in there give it all a clean like this 




Give the sprocket cover a clean too and re grease the piviot points and while you are there take off the clutch cable and re lube

[anutz]

Thanks fazer#


Shall have a read, i have wrenches etc...


Just debating if i need loc tite....

[anutz]

Silly follow up question.....it has got me stumped....how do I remove the clutch cable?

I have removed throttle and choke cables and re-assembled, I don't see how to get the nipple out of its housing...I hope its called a nipple..

 

[fazersharp]

On my picture above you will see the part marked "tab" you need to bend this down and that will give you slack space to push the nipple down and clear its holder
Its all on the link I gave that you have not read 
All about the crank case cover here http://foc-u.co.uk/index.php/topic,10124.msg105271.html#msg105271

Here is the part on the link you need

The tab "C" has to be bent down to enable enough slack to push the cable down enough to slide it out of the slot. The area between "A" and "B" will not pass through the slot as the slot is only wide enough to let the bare cable pass.
If your tab has not been bent back up after removing the cable or if it has snapped off. then your cable nipple part "A" will fall below the hole at the end of the cable slot, when you then pull the leaver  point "A" catches on the slot/ hole and then slips off and catches onto point "B" with a "click" where it should of been all along and helped to stay there by the tab.Or it is even doing the same but catching on what remains of a broken off tab.
Also the photo looks like it go's in from the front but it dosent - it slides in from the left like the diagram

[anutz]

thanks - not reading links again - sorry, been distracted with the cylinder head 

[fazersharp]

Also on my photo there is a panel with 4 screws that was not fitted to newer models so you may not have this