|
Post by noonster on Dec 13, 2018 8:54:39 GMT 1
Just bought a restoration project. When I removed the gen cover, I noticed the locking tab was knock over onto the nut,but there was movement in the sprocket .
I can see the sprocket thickness is about 8-10mm,Nut is tight.think I can see the spacer behind the sprocket.
I can even slacken the nut off.
Tried a small impact wrench I have,still will not move. its a r/h thread or l/h
Any ideas to get the nut loose please and what to look for why sprocket isn't tight on shaft.
Thanks
|
|
|
Post by bazzer5115 on Dec 13, 2018 9:10:05 GMT 1
R/H thread so anti-clockwise to undo. I’ve always managed to undo them with an impact gun,but if if particularly tight,get the nut hot,best use oxy-acetaline for better pin-point heating. I’ll be interested to know why nut tight but sprocket loose,as I’ve just built a lc engine to go in friends hybrid and having same trouble. Have gone for 520 conversion and if I use ypvs spacer I can’t fit tab washer on and if I use lc spacer the nut bottoms out? Can only get it tight with 2 spare tab washers behind the sprocket?
|
|
|
Post by dusty350 on Dec 13, 2018 17:09:57 GMT 1
Is it the proper sprocket nut I wonder ? Proper one is recessed and sits over the end of the gear shaft. So a normal nut will tighten but not contact the face of the sprocket as the splines of the shaft will contact the nut.
Dusty😉
|
|
|
Post by bazzer5115 on Dec 13, 2018 17:26:22 GMT 1
Mine is the proper one,and it would be difficult to get a normal nut without the recess because of the size and pitch of the thread. So I don’t know what is going on with mine,thinking I may have assembled gearbox wrong,but I done a lot of these and I got all the gears shifting.??
|
|
|
Post by midlifecrisisrd on Dec 13, 2018 17:38:45 GMT 1
Mine is the proper one,and it would be difficult to get a normal nut without the recess because of the size and pitch of the thread. So I don’t know what is going on with mine,thinking I may have assembled gearbox wrong,but I done a lot of these and I got all the gears shifting.?? Is the clutch centre nut not the same without the recess Also if it is an lc with the correct lc sprocket spacer but a 520 sprocket will it bottom out before hitting the sprocket Stevr
|
|
|
Post by dusty350 on Dec 13, 2018 18:58:24 GMT 1
Correct regards the sprocket and clutch nut Steve. Internally the same but sprocket nut is a 32mm spanner and clutch is 30mm so that will give you a clue if a clutch nut has been used by mistake.
Dusty
|
|
|
Post by noonster on Dec 13, 2018 19:48:29 GMT 1
Been using a 32mm socket to try an loosen the locking nut
|
|
|
Post by dusty350 on Dec 13, 2018 19:52:49 GMT 1
Doesn't sound like the clutch centre nut then.
Dusty
|
|
|
Post by bare on Dec 13, 2018 19:55:15 GMT 1
A 520 sprocket is 1/8" thinner than the 530 the LC shaft spacer was designed for. Must! fit an 1/8" thick washer to the sprocket to make up the distance. So the nut can tighten..Before it bottoms out.
|
|
|
Post by dusty350 on Dec 13, 2018 20:04:21 GMT 1
If it helps, a standard Lc front sprocket is approx. 9mm thick Dusty
|
|
|
Post by badger1 on Dec 13, 2018 21:01:24 GMT 1
A 520 sprocket is 1/8" thinner than the 530 the LC shaft spacer was designed for. Must! fit an 1/8" thick washer to the sprocket to make up the distance. So the nut can tighten..Before it bottoms out. I put a clutch basket thrust washer behind mine fits perfect.
|
|
|
Post by noonster on Dec 13, 2018 21:52:50 GMT 1
The sprocket measures roughly around 8.7mm in thickness.
centre nut as a recess in the middle.
show i have a nut,tab washer,sprocket,spacer behind sprocket to casting.
so do you think i need to put a 1/8th washer behind the sprocket to take the slack up.
will this keep the alignment ok of the chain
|
|
|
Post by bazzer5115 on Dec 14, 2018 0:05:53 GMT 1
This first LC engine hybrid build for me(usually do ypvs engines) Building it for a friend,didn’t realise everyone were spacing front sprocket out with extra 1/8” spacing behind sprocket,nobody mentioned it when using 520 chain. I tried using ypvs spacer but they slightly to wide and couldn’t use tab washer. I knew LC were 530 chain and ypvs 520 chain so thought ypvs spacer on shaft when using 520 chain would be right,but no it too long and tab washer wouldn’t go over splines.
|
|
|
Post by bare on Dec 15, 2018 23:59:56 GMT 1
1/8" spacer/washer goes... betwixt... Sprocket nut and Sprocket. Keeps the alignments with the LC rear wheel.. IF using it.
|
|
|
Post by wiggy92000 on Jun 6, 2022 14:17:49 GMT 1
Hi all what is the correct nut size and thickness of the nut so clears the swing arm cheers
|
|
|
Post by stusco on Jun 6, 2022 15:31:19 GMT 1
Hi all what is the correct nut size and thickness of the nut so clears the swing arm cheers Sorry I don’t understand the question? what nut are you asking about ?
|
|
|
Post by wiggy92000 on Jun 6, 2022 17:38:59 GMT 1
Hi sorry rear sprocket on back wheel thickness of the nuts what secure sprocket to the wheel mine is 250lc
|
|
|
Post by stusco on Jun 6, 2022 18:05:17 GMT 1
Item 12 standard m10 nut i can’t remember my tech drawing days but there is a formula ,ideally you need a thread sticking through the nut when built up,so your nuts are never going to touch the swingarm😱 anyway
|
|
|
Post by chrisg on Jun 6, 2022 21:02:29 GMT 1
Before my magic impact tool I managed to loosen the sprocket nut by putting a piece of wood between the rear wheel spokes and using a breaker bar with another bar, so maybe 3ft and it took some loosening. Im not sure why it has to be like that as its locked in place. Try not to hit the breaker bar, just use progressive force.
|
|
fabiostar
Thrash Merchant
the older i get the faster i was.
Posts: 409
|
Post by fabiostar on Jun 9, 2022 18:40:53 GMT 1
i always wondered why did yamaha use a dirty great 530 chain in the first place?
|
|
|
Post by JonW on Jun 10, 2022 1:19:25 GMT 1
i always wondered why did yamaha use a dirty great 530 chain in the first place? I think they worked on the principal that a 350 two stroke was like a 750 4 stroke of the 70s, so that meant it needed the 750s chain size, which was 530. Its defo over size for what you need on an LC. Whats the AC models use?
|
|
|
Post by JonW on Jun 10, 2022 1:52:53 GMT 1
Hi sorry rear sprocket on back wheel thickness of the nuts what secure sprocket to the wheel mine is 250lc I think what youre asking is the thickness of the 250 nuts? If so I dont have one handy, but they are defo thinner than you would think and are a special nut. You should be able to measure the depth of the stud and with the thickness of the sprocket and spacers work out what thickness but you need if you cant/wont order new ones from yam.
|
|
|
Post by steeley on Jun 10, 2022 5:01:04 GMT 1
i always wondered why did yamaha use a dirty great 530 chain in the first place? I think they worked on the principal that a 350 two stroke was like a 750 4 stroke of the 70s, so that meant it needed the 750s chain size, which was 530. Its defo over size for what you need on an LC. Whats the AC models use?
|
|
|
Post by steeley on Jun 10, 2022 5:03:42 GMT 1
I believe air cooled 250/350 were 530 . Been a while since i rebuilt a 250e .
|
|
|
Post by 4l04ever on Jun 10, 2022 6:27:24 GMT 1
I just remembered, I saw this issue on the red seat hybrid in the past... It was an issue with the sprocket spacer being machined too narrow, to the point that the sprocket was bottoming out on the end of the splines before it locked against the spacer.
Had to get a new spacer the correct length.
|
|
|
Post by shaunthe2nd on Jun 10, 2022 7:38:26 GMT 1
Hi sorry rear sprocket on back wheel thickness of the nuts what secure sprocket to the wheel mine is 250lc The nuts on a 250LC wheel are 6mm thick.
|
|
|
Post by pdxjim on Jun 10, 2022 15:48:34 GMT 1
|
|