Clutch and shock absorber problems

[sprint]

Had the bike a few weeks now, RGS, but several things I wanted to sort out so I have only had a chance to ride it today and have immediate clutch problems?

Started the bike and pulled in the clutch but when I let it out again there was more or less full play on the cable. Pulled it in again and then it was back to normal.

Stopped the bike and pulled in the clutch kicked it over with the clutch in and then released it full play in the cable. Depressed the kick lever and then the cable returned to normal.

No option but to take the chaincase cover off.

With reference to the photos what I find is that a Triumph type clutch fitted but what is happening is that when you pull the clutch in and with the clutch turning the top friction plate rides up on top of the basket and so when you release the cable it can't engage into the slot which is clearly not right.

There are 6 plain plates and 5 friction plates and there simply seems to be to many for the basket? Further there is no friction material at the base of the basket and whether you put a plain or friction plate in first it does not rest onto the bottom of the basket but stands proud of it as it rests on the base of the hub? Is that right? It means that the basket/chainwheel is not in any way bonded to the pates and hub under spring pressure and that the plates only engage via the tangs on the edge of the friction plates?

The only way this assy can work if one of the plain and friction plates be removed so that there is only 4 friction plates but then the clutch push rod is too long that does not seem right and what is the position with the first plate not actually bonding with the basket? My understanding is that there should be 5 friction plates so something is clearly seems amiss with this assy.

Further, can somebody advise if the shock absorber assy is right?

Is the engine sprocket and shock absorber cam bearing too long? The fitted tab washer does nothing as the folded inner tangs do not engage with anything as the bearing stand proud of the splines on the mainshaft on which they would correctly engage? (with the tab washer turned around)

The end nut is wearing on the inner chaincase. The end face of the nut stands about 60mm proud of the inner chaincase face which is more than the clearance available inside the outer chaincase, which indicate that the bearing is too long?

What should be the correct height of the shock absorber spring?

Some help and advise would be appreciated on both of these problems.  
 

[chaterlea25]

HI Andy,
First of all theres a non standard piece inside the engine shaft shockabsorber sleeve ??
Can you pull this out and let us see what it is? theres a sleeve which should fit inside the seal and butt up against the crank end (chamfer on the inner bore faces intowards crankshaft)

A shock absorber type clutch centre wont make any difference to riding the bike (if its there let it alone)
It looks as though you have too many plates fitted, it should be 6 plain and 5 friction
(assuming they are standard thickness)
Yes its "normal" for the first plain plate to sit on the lip on the centre (later Triumphs added a friction plate first and removed the lip from the centre) but have a thrust washer between chainwheel and shaft adaptor
Then of course there were different depth centres and baskets for lower powered models or early Triumphs which have less plates fitted !!!!
The outer most plain plate should not be able to come outside the basket as is happening to you
Without having all the parts in my hands its hard to see whats the problem or problems

I have come across more problems with different A series bikes with the primary side assembly than nearly anything else,
Whether this is down to pattern parts or incorrect parts and or incorrect assembly is always a headache

It is very important to get the primary chain aligned properly, sometimes shims are needed between the shock sleeve and the crank collar
The inner casing should be spaced out correctly without strain where it bolts to the frame near the footrest shaft
and the plate between crankcase and inner primary fitted ( yes I have come across this missing!!!) allowing the primary to be fitted in too far  causing more problems
Finally the crankshaft and clutch centre nuts must be tightened properly 65ft lbs
I dont bother with the crank lockwasher and use threadlock

HTH
John

[sprint]

Hi John

Thanks for the replies.

Are these the non-standard parts you are referring to?

They look to have been added to space the engine sprocket to align with the chainwheel sprocket, which they seem to do. They are much thicker than the std shims you would expect with a combined thickness of about 3mm but I guess that is what comes with mixing parts? Is this likely to be the cause of the nut rubbing the inside of the outer case? I guess the only solution is to relieve the outer edges of the nut?

The crank collar is correct with the chamfered inner edge facing inwards.

As I indicated in my original post the clutch assy currently has 6 plain plates and 5 friction plates and as such too many for the existing basket which is why the top friction plate rides up on top of the basket? The only way this basket can be used is to reduce the number of plates to 5 plain and 4 friction is that right with only 4 friction plates?

The plain plates are approx 2mm thick and the friction ones approx 4mm thick.

So with this assy (assuming it is correct) the drive between the basket and hub is totally via the tangs on the friction plates because the bottom plain plate sits on the inner lip as you advised? Not a very good design as it means all the load is transferred to the bottom plain plate which rests on a 1 mm or so lip, is there not a danger of the bottom plain plate bending as it is not supported at its outside edge?

Got to inspect the inner case spacing as it does not look like the parts in the book, see photo, with the outer face bolted directly to the frame brk no spacer as indicated in the parts book, is this right?

The plate between the inner case and the crankcase is present with gaskets either side?

I take it the crankcase nut you are referring to is the one on the timing side and not the the one on the end of the shock absorber?

What is the position with the shock absorber tab washer, is the one I have correct?

Have included a photo of the spring which measures about 39mm across its faces, does it look right?

At the moment I am at a bit of a loss what to do, particularly with regards to the clutch as with 5 friction plates it will ride up onto the basket but 4 will be too few and not provide enough grip?

Anybody else come across this problem?

[Topdad]

Hi Sprint, by pure coincidence another forum member contacted me earlier this week and during the conversation he told me His triumph clutch was one of the "other types " fitted to something like a 5TA OR 3TA, anyway he couldn't fit all the plates without a problem  which may be as per yours, He'd decided to fit less plates and see how it went and at that stage he was happy ,no slip and a light action. So my advice would be ,try it with less plates so that its not above the basket and see how you get on nothing ventured etc ! At worst it's another excuse for a ride and the weather may be ok ! By the way try it without the casing on, surprising what you can see with it like that ,I'd choose a quite road though ,you can get engrossed . Then clean it up and if okay put her back together and enjoy, best wishes BobH

[muskrat]

In picture #624 there looks to be another spacer behind the collar. The collar should butt against the inner race of the bearing.
Friction plates at 4mm thick seem a bit too thick.
Cheers

[sprint]

Hi Sprint, by pure coincidence another forum member contacted me earlier this week and during the conversation he told me His triumph clutch was one of the "other types " fitted to something like a 5TA OR 3TA, anyway he couldn't fit all the plates without a problem  which may be as per yours, He'd decided to fit less plates and see how it went and at that stage he was happy ,no slip and a light action. So my advice would be ,try it with less plates so that its not above the basket and see how you get on nothing ventured etc ! At worst it's another excuse for a ride and the weather may be ok ! By the way try it without the casing on, surprising what you can see with it like that ,I'd choose a quite road though ,you can get engrossed . Then clean it up and if okay put her back together and enjoy, best wishes BobH

Thanks Bob

That seems to be the only option for me at the moment as it definitely can't take 5 friction plates.

[sprint]

In picture #624 there looks to be another spacer behind the collar. The collar should butt against the inner race of the bearing.
Friction plates at 4mm thick seem a bit too thick.
Cheers

That's very observant of you. Had a check and yes there seems to be a thin shim between the dist piece and the bearing as well. Can't get it out as its larger that the oil seal and I don't want to damage that. With it fitted plus the outer two 3mm thick spacers the clutch and engine sprocket line up so there is no need to remove it?

The friction plates, including the friction material, is 4mm thick. Plate is 2mm, same as the plain plates, so 1mm friction material each side seems to be right?

Can you advise on the tab washer. Is the one I have correct and do the other parts of the shock absorber look right?

[sprint]

It's been suggested that I should simply re-build the clutch with just 4 friction plates.

However, that will cause a couple of slight problems:

1. Getting the correct spring tension since I will now be two plates less and screwing down the spring nuts may be a problem as they will be well recessed?

2. The clutch push rod is going to be a bit too long?

In order to minimize the problem could I use two plain plates together either at the bottom or top as that would mean only one less plate?

[Topdad]

hi again, don't think the springs will pose a problem ,you're just going slightly further down the stud before you start to tension them and with regard the pushrod just adjust accordingly from the oval inspection plate on g/box end cover if really to long shorten and harde the cut end but not before making sure you don't have to fit more plates as per your point about only fitting 1 plate less ie trial and error until you find the whats right for your parts. regards BobH

[chaterlea25]

Hi again Andy,
Some pillock has added all those shims because the wrong ( or poor pattern) clutch adaptor has been fitted
There have been a lot of crap adaptors on the market in recent years, even ones with the scroll cut in the wrong direction 
Firstly I would remove the clutch and adaptor,
post a photo of how far it sits onto the gearbox shaft, so as a judgment can be made
The added spacers have  been the cause of the shock nut rubbing on the case
It also looks as though the inner primary case is spaced out a lot????
I think the spacer ring is about 90 thou and 2 thin gaskets,

From your photo it also looks as though the seal will be running on the edge of the correct spacer ???
It's easy enough to pop out the seal and fit a new one

At the rear mounting near the footrest its usual to make up the space with stacked washers as the measurement varies from bike to bike

The nut I was on about is the one which holds on the shock absorber spring / cush drive,
a special tool (ebay)or an adapted socket is required to tighten this, (or a nut with hex from SRM ).
 A "C" spanner is not good enough 
This nut holds the main bearing to the crank and any crank spacing shims between the bearing and crank
if these work loose they will break up and replacement involves a complete engine strip

Measure the depth of the clutch basket, and the centre carrier and I can compare with what I have here

Yes the clutch is not the cleverest design in the World 
The innermost plain plate can flex under the spring pressure ?? Its possible to add a either a modified friction plate
or to remove the lip from the centre carrier and let the plates up against the back of the clutch basket
The slots in the basket will need deepening to let the friction plate sit against the basket
BUT doing this means steel running on steel whilst the clutch is engaging 

Burman clutches use a thick plain plate at the back to resist flex

HTH
John

[muskrat]

And as a side note. The two inner primary bolts directly to the rear of the crank must be lockwired or a long tab washer between the two (like what they use on Asian rear sprockets).
Cheers

[sprint]

Hi again Andy,
Some pillock has added all those shims because the wrong ( or poor pattern) clutch adaptor has been fitted
There have been a lot of crap adaptors on the market in recent years, even ones with the scroll cut in the wrong direction  
Firstly I would remove the clutch and adaptor,
post a photo of how far it sits onto the gearbox shaft, so as a judgment can be made
The added spacers have  been the cause of the shock nut rubbing on the case
It also looks as though the inner primary case is spaced out a lot????
I think the spacer ring is about 90 thou and 2 thin gaskets,

From your photo it also looks as though the seal will be running on the edge of the correct spacer ???
It's easy enough to pop out the seal and fit a new one

At the rear mounting near the footrest its usual to make up the space with stacked washers as the measurement varies from bike to bike

The nut I was on about is the one which holds on the shock absorber spring / cush drive,
a special tool (ebay)or an adapted socket is required to tighten this, (or a nut with hex from SRM ).
 A "C" spanner is not good enough  
This nut holds the main bearing to the crank and any crank spacing shims between the bearing and crank
if these work loose they will break up and replacement involves a complete engine strip

Measure the depth of the clutch basket, and the centre carrier and I can compare with what I have here

Yes the clutch is not the cleverest design in the World  
The innermost plain plate can flex under the spring pressure ?? Its possible to add a either a modified friction plate
or to remove the lip from the centre carrier and let the plates up against the back of the clutch basket
The slots in the basket will need deepening to let the friction plate sit against the basket
BUT doing this means steel running on steel whilst the clutch is engaging  

Burman clutches use a thick plain plate at the back to resist flex

HTH
John

Hi John

Thanks for your very detailed replies.

I have added a load of photos which will hopefully help.

1. Clutch hub adapter. Does it look right? I think the rear spiral groves are going the correct way.

I have loose fitted it to the mainshaft, with and without inner cover.

2. The solid spacer plate measures about 0.1" (100 thou)/2.4 mm and each gasket measures about 03" (30 thou)/0.8 mm giving an overall thickness of 0.16" (160 thou)/4 mm, is that OK or should thinner gaskets be fitted, assuming they are available?

3. Added photos of oil seal distance piece fitted and removed. I think fitted it is OK with the seal not on the edge?

4. Added photos of the S/A nut which I assume is right one but does not lend itself to being tightened by anything other than the C-spanner. Understand the importance of having everything tight and not moving around but is not the drive side main bearing a two part roller bearing that slides anyway to allow for the slight side play that is inevitable under what is only the spring tension from the S/A spring with the end play that has been set during build with the use of appropriate shims?

If the nut were to be loose surely the crank would still only move the same amount of the end play that has been set?

5. Clutch basket measures about 30 mm deep and the center carrier about 35 mm to lip and 38.5 mm overall.

Not sure that I want to be modifying either the basket or the center unless it is really necessary. It has been commented that using just 4 friction plates is OK, I will not pushing the bike in anyway. So I might go this route initially and if all is OK then leave at that?

My plan was to double up on the plain plates at the bottom and then alternate friction and plain plates and that the seems to leave enough room for the top friction plate to move without riding up on top of the basket? That way there is a double thickness of plates at the bottom and I only loose one plate which helps with the spring tension and the clutch push rod.

Will appreciate you comments and advice.

Have also replied to you comments and advise about the gearing.

Thanks

Andy

[A10Boy]

I suggest getting everything back to Std including removing the seal and that odd spacer. Assemble it as per the parts diagrams [which are available online] with no additional parts. The clutch adapter looks ok to me, so thats good. Not sure on the 30mm in the basket, it does look slim but I havent got a spare basket to hand but someone will measure one for you.

While you're at it, check the end float on the crank in case some muppet has bodged that too.

BTW, the load through the clutch is taken up by ALL the tangs on the friction plates, not just one.

[sprint]

Thanks A10boy

Do you mean the shim that is between the oil seal dist piece and the bearing? If so to remove it will mean destroying and replacing the oil seal? I will then have to re-used it the other side of the dist piece as it adds up to shimming the engine sprocket to align with the clutch sprocket.

You indicate that the clutch adapter looks right so is it normal to have to shim the engine sprocket by as much as 3 mm?

What is the acceptable max end float for the crank?

[BSA_54A10]

Me thinks that your basket is off a single wich not having as much grunt got less plates.

If your stack ends up a little short ( sounds a bit naughty doesn't it ? ) then double up on the plain plate nearest the pressure plate.
When I were young & pennyles ( as distinct from being old & broke ) we would oft use a extra plain plate or two to pack out the clutch & get the last 0.0001" out of the friction plates.
Bike Beesa
trevor