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4 SPEED SPROKET NUT

Posted: Fri May 18, 2012 9:28 pm
by Jack
Hi folks,i've just noticed that the sprocket (2001 535cc Lightning 700 miles )has some movement when rocking the wheel(back and forwards,1/16"or more)and yet the large nut doesn't move with it.Is this normal?I would have thought they would be locked together
real tightly
Jack

4 SPEED SPROKET NUT

Posted: Sat May 19, 2012 12:24 am
by John L
Jack -
If it's the gearbox sprocket you are referring to, then the nut is loose.
It should have a lockwasher, which if tabbed over will prevent the nut from coming undone totally and actually falling off. However, as the lockwasher is just mild steel it's possible for even a tight nut to dig into it and become loose. You'll need to tighten it to prevent further wear to the splines on the sleeve gear and sprocket - and to prevent possible oil leaks.

4 SPEED SPROKET NUT

Posted: Sat May 19, 2012 12:25 am
by John L
Jack -
If it's the gearbox sprocket you are referring to, then the nut is loose.
It should have a lockwasher, which if tabbed over will prevent the nut from coming undone totally and actually falling off. However, as the lockwasher is just mild steel it's possible for even a tight nut to dig into it and become loose. You'll need to tighten it to prevent further wear to the splines on the sleeve gear and sprocket - and to prevent possible oil leaks.

4 SPEED SPROKET NUT

Posted: Sat May 19, 2012 5:23 am
by Beezabryan
I will say this only once ;) Learn form my mistake.
Retighten the nut or you will get spline wear and I mean tight. You can re-use the lock washer. I did not notice movement for a long time & when I did I ignored it for some time, resulting in badly worn splines, That means at some stage like one winter I will have to buy a replacement mainshaft sleeve at £56 plus postage and do a geabox strip :( And all because I could not be bothered to dismantle the primary drive & do a bit of maintenance.

4 SPEED SPROKET NUT

Posted: Sat May 19, 2012 7:57 am
by Les H
Hi Jack. Yes as per John and Bryan. I would also use Loctite Threadloc or similar on the threads of the nut. Other makes of gearboxes use a small screw to hold the tab washer solid to the sprocket to ensure no relative movement. Perhaps some owners might try the same mod.
if there is any sign of an oil leakage from the gearbox output shaft, then you might as well replace the oil seal at this time, when you replace the tab washer. Tightening Torque is 70NM or 52 Foot Pounds in old money. That is nearly half a hundred weight pressing down at a full 12 inch distance on a long tommy bar!...............http://www.hitchcocksmotorcycles.com/pi ... bullet.pdf

4 SPEED SPROKET NUT

Posted: Sat May 19, 2012 11:09 am
by Jack
Thanks guys,darn so off with the primary with a motor not even run in.So i'm assuming there's a loose fit between the sprocket and sleeve gear.Jack

4 SPEED SPROKET NUT

Posted: Sat May 19, 2012 11:25 am
by Alan R
Hello Jack ---- Have a look at this }---http://www.loctite.co.uk/cps/rde/xchg/h ... e&B------- and this }----http://www.loctite.co.uk/cps/rde/xchg/h ... ryCode=uke -----I personally use 243 for all my Enfield applications 'cos you might just need to dismantle, maybe not to-day, maybe not tomorrow but-------------------------------- ?? I've used 272 professionally and can vouch for it's more "permanent" nature. In your case---as there is also a tab washer involved, then the 243 would be OK. good job you spotted it when you did. I'll go and give my 2 bikes a quick check now------you never know ??.

4 SPEED SPROKET NUT

Posted: Sat May 19, 2012 11:30 am
by Alan R
---------------sorry, both those links came out the same !!. Look at the THREADLOCKING headings and in particular 243 and 272. Why is this screen so W-----I-----D-----E ?????????

4 SPEED SPROKET NUT

Posted: Sat May 19, 2012 12:49 pm
by Jack
Alan i was thinking along those lines,after the replies here.There is a small gap and i can clearly see a brand new shinny nut.I'll see if i can bend the tab back and insert a spanner suitably ground down,heck the imagination is running wild now!!Have got a ride on tomorrow on the 500 Twin so it'll have to wait.Any idea of the size nut?
Jack.

4 SPEED SPROKET NUT

Posted: Sat May 19, 2012 9:27 pm
by Norm
Biggest problem with a loose nut is the distance piece which sits in the oil seal stops turning because of the resistance of the seal and the sprocket cuts into the distance piece which then makes for even more clearance and slop. The nut being tight is only relevant to the condition of the distance piece.When you remove the sprocket, check the distance piece and if it shows signs of wear replace it, but at 700 miles it shouldn't be worn