4 spring clutch lockwasher, recessed washer and nut

[berger]

I know nothing of the 4 spring clutch but now I am more confused than ever. the nut goes in a recessed washer that on studying doesn't make sense. the recess gets covered up when the lock washer is fitted. if the lock washer goes on nut first it doesn't reach the flat on the clutch inner drum, what am I missing apart from brain cells?

[JulianS]

Like this.

My washer is a thick plain one no recess and since the photo was taken I no longer use the lock washer, just thread locker.

[chaterlea25]

Hi Berger and All,
+1 on the thread locking compound
My Theory is that the lockwashers are soft so that they squash over time and reduce the pressure of the nut
A side story,
There was one of the famous race bike tuners who insisted on no washers being used on any part of the bikes he built
insisting that the did not serve any useful purpose only extra weight 

John

[berger]

thanks for quick reply's , I am under the impression that the recess is for a clearance for some reason but on studying it I find it doesn't clear the centre to make it contact fully only with the drum. Julian S my drum is same as yours, so I could have just used a thick washer instead of buying the special one that is confusing me. all I do know is a mate cracked his washer over tightening it when he had it on the wrong way thinking the recess was for the hex head on the nut to fit in. at the time he did this his clutch was snatching and I told him he had the washer on wrong and the recess was for a clearance and when he put the new washer on the correct way the clutch was ok, so I still don't understand it if your clutch works ok with a flat washer.

[berger]

I should have added his clutch snatched with the washer on the wrong way but he didn't have a lock washer on it, anyway does this look right or should the nut protrude through the lock washer? if it doesn't have to protrude through the lock washer why has the lock washer got the same size hole as the washer because it just flops about on the mainshaft?. is this a case of pattern part mishmash again. I might put the nut in the lathe and take a bit off so it holds the lock washer. edit, and this recess in the washer is really bugging me because with the lock washer on it serves no purpose--- what is going on..... I might have to go to the pub at this rate. thankyou for listening to my troubled mind but this set up makes nonsense to me

[JulianS]

Clutch works fine with the thick washer.

It is about 5mm thick.

I torque to as close to 60ft/lbs as I can get.

I cannot see it cracking.

Photos complete with old thread locker waitng to be cleaned off.

[berger]

yes thanks JulianS maybe yours is original nut and it pokes it's nose out a bit with your approx. 5mm washer, ok the sticky out bit on my pattern nut is only 4.25 mm and lock washer + recess washer is 6mm. so that answers another pattern part syndrome I think. BUT why do these clutches have a clearance recessed washer when apparently it doesn't need one- especialy when the lock washer covers up the recessed bit when it is all together, that bit does my head in

[trevinoz]

I think that you will find that the recess goes against the hub.

[berger]

the recess goes to the hub, well it can't be doing a job when there is a lock washer fitted because that spreads itself on the hub and centre faces, this is what is confusing. I thought wrongly or rightly that the nut pushed against the centre on the taper and the recessed washer pushed against the hub. but as I said with a lock washer fitted that theory is ruined because the washer is wide and covers both centre and hub. anyway it is now on and the next problem was two clutch cables with adjuster to fit the gearbox sandwich plate thread and these didn't allow enough inner to set the arm up properly.- pattern parts , so the  old cable has gone back on with adjustment at handle bar lever and ferrule butted up to the sandwich plate, much swearing and hours gone by and the jobs a gooden at last

[trevinoz]

I think the recess is to clear the sleeve gear so that the hub and gear don't lock together.
Lock washer goes between nut and thick washer.
If you have rubber and vane type centre from an alternator bike there is no easy way to fit a lock washer.

[chaterlea25]

Hi Berger and All,
When the inner drum is fitted onto the shaft adaptor it should sit a little proud on the outer face where the washer sits against it
The purpose of this is to firmly clamp the drum to the adaptor
A recessed washer could help the clamping if the recess is big enough to clear the shaft adaptor
Its not the best design in the world as damage /wear to the very small rear face where it sits against the adaptor shoulder can lead to the bearing rollers being pinched endways and jamming

The cush drive inner drums are prone to wear in this area
For some reason that I do not know the answer to worn components of cush drive inner drums also cause clutch slip 

John

[berger]

your on it again john that is why you must fit the correct size rollers so the inner and outer don't lock up , now I know we are not thick but having the recessed washer to clear the centre and contact the drum is common sense, but what I have is the recessed washer made in such a way it interferes with the drum and the centre . even if it only tightened the drum up on the centre when you add the lock washer to the equation it has enough area to cover both parts so as the parts book shows this lock washer why not just have a thick plain washer. the lock washer makes the recess redundant

[berger]

trevinoz if I put the lock washer between nut and washer the tab doesn't reach the flat on the drum, parts book shows it goes between washer and drum . so is parts book wrong and the other bits not made as good or accurate as original parts, like the nut that needed loads of attention to the threads.

[ironhead]

G'day Berger.
Julian is on to it. Bin the tab washer & recesed washer. Use the thick plain washer & something like 262 loctite.
  If you are using a "pattern" shaft adapter, dry assemble the hub to it to make sure the hub splines are 1or 2 mm proud.
If not , grind that amount off the adapter end.  Had to do this recently to a "pattern"  Trihard  adapter.
Easy

[berger]

thanks for input ironhead, I understand how it should fit but putting it together by the book with a recessed washer and a big plain lock washer makes the recess null and void. if the lock washer had a bigger hole and just mated with the outer of the recessed washer it would make more sense to me. anyway it is now all in situ and I am setting up the spring tension so even though the engineering side has had me stumped-[it wouldn't have if it were not for the lock washer] the show goes on and after I pulled in the clutch lever it is so easy compared to the 6 spring I will not be breaking brazil nuts between finger and thumb next christmas