1000 Primary chain alignment.

R

Rocker Arm

New member
Location
Burnham Buckinghamshire
I have just free'd off a stuck clutch on my 1000, prior to me purchasing the bike, it had been completely renovated and then left,

On re-assembly the Primary socket and and clutch housing sprockets are not aligned. The clutch housing is too far in towards the engine by 0.090".

There are no shim washers fitted to either shaft!

If I put such a large shim on the inside of the clutch housing, moving it outwards, I am worried the clutch housing will not engage with the first friction disc. Also I will not be able to fit a shim between the housing and the circlip!

The clutch housing fitted has the sprockets rivetted to it, presumably no rubber dampers fitted. This is an early bike, was this how the early ones were built?

My best option is to machine the face of the smaller primary sprocket to allow it to move in towards the engine and aligning the chain.

I have checked the clearance between the oil pump sprocket and chain there is a big enough gap to allow me to do that.

Any thoughts?
 
0.09, is that inches? That would be 2mm.
What do you call clutch housing?

If it's the external drum with the drive sprocket, you'll have no problems with the clutch particularly as a 1.5mm shim will be fine, there must be some free play. There's a factory spec for that which I forget.
Clutch sprocket is riveted ex factory and there are rubber shock absorbers behind the sprocket.

What do you call an early bike?

Paul
 
it is normal to find shims inside and outside the clutch drum, can you move the drum in and out to the extent that you desire, indicating enough space for the shims, it matters not which end is shimed, plus both ends = no problem, I take it that becaue of the " you are looking to close up 90 thou (inches), but Froglet Marx probably cant focus on the ". The rivets indicate that the cush drive rubbers have not ever been changed, none of them were mounted without them, early or late, time alone suggests that you need to change them, grind the rivet heads off and punch them out, a little heat helps loosen them, (the pillars can be fragile) then tap threads and replace the rivets with bolts, again usually 6mm is correct but occassionally the holes are too big for the tapping size and would result in incorrect or incomplete thread forms, so 7mm ones are sometimes needed, not so readilly available, (the bolts or the taps), I have the taps witch I would loan out subject to a substantial deposit but am currently out of bolts, try Modern Screws Dartford, who I have always found to give excellent service.

chain alignement is vital with any chain running at that speed, (or any speed) I favour the triplex, and you can buy them very cheaply from Norton Commando dealers (the old/original 70's/80's bikes) but they are a tad too long and need to be shortened, not for everyone, is that process, it requiring some tooling and ingenuity, plus you must have three rows of teeth, which may not be the case.

get your gaskets from Phil Todd and tell him I sent you (I also have them in stock)
CLEM
 
Thanks for the prompt replies.

The bike hasn't been ridden since it it's restoration, everything is spotlessly clean inside, the chain and sprockets look new, and the sprockets have sharp edges to them. but all that glitters is not gold! However as it looks new I don't think it is worth de-riveting the drum to inspect the dampers.

Who ever built it did not pay that much attention, no shims fitted at all. A bit concerning.

The Clutch housing/external drum can move up and down on the shaft, if I shim it out and move it as far out as I can i am worried the first clutch plate will not engage on the drum!

I live near Slough and have a good supplier of fasteners near me, I will get a selection of hardened washers, and carry out some experiments, and let you know how I get on.

Now to clean the tank.

Les
 
It is not just normal, but specified with washers both sides of the clutch drum. See part #34

Chapter 47

Clutch
www.laverda-paradies.de
With these shims there should be no problem with engaging clutch plates.
On some bikes there was a shim behind the crankshaft sprocket to align them correctly, which as Clem says is vital. Advice if removing the mentioned rivets is to in fact drill through their centres first to relieve the pressure before driving them out.
 
The clutch drum MUST have a thrust washer on both sides of the bearing, axial clearnce can be adjusted with shims under the circlip, but is seldom required. The stock thrust washers are 1mm thick and hardened! Chain alignment is adjusted by shims under the crank sprocket.

The internal splines of the clutch drum are long enough to engage the plates when the drum is moved outwards as far as it might go.

piet
 
This image is from the 1200 parts book. Items 43 as mentioned in the above post should be in place. I see you are in Burnham. I am in Reading.img013.jpg
 
I have not been able to find hardened washers, I have temporarily placed a brass washer on the inside. This washer is 0.075" thick, with this in place the sprockets are aligned.
This doesn't allow for a washer to be placed on the outside. With the circlip installed there is only room for a gnat's cock between the drum and the circlip. But as they all rotate together there will be no wear, so should be o.k.

The tank is drying in the sunshine after applying corrosion inhibitor.
 
Rocker Arm said:
I have not been able to find hardened washers, I have temporarily placed a brass washer on the inside. This washer is 0.075" thick, with this in place the sprockets are aligned.
This doesn't allow for a washer to be placed on the outside. With the circlip installed there is only room for a gnat's cock between the drum and the circlip. But as they all rotate together there will be no wear, so should be o.k.

The tank is drying in the sunshine after applying corrosion inhibitor.
Click to expand...
There will be wear... seen enough of these that have chewed themselves up.

Your 0.075" washer is almost double the thickness than it should have, it's already disturbing proper chain alignment.

Mainshafts are pretty rare these days, and quite expensive should you find one.


piet
 
Leave the clutch alone. Facvtory fitment - a shim on the inside and one on the outside with the circlip fitted. As Piet pointed out, align the chain using a shim begind the crank sprocket - it doesn't even have to be hardened.
 
Yes something appears not to be correct. I have ordered shims from Germany,they are not confident they will turn up, as the U.K. left the EU.

No shim under the crank primary socket.

The clutch drum to gearbox shaft gap is correct i.e. a total of 2mm to the circlip, so nothing is worn.

The plan is to install 1mm shim/washer either side of the clutch drum as standard. Then machine 1mm of the face of the crank sprocket to bring into alignment.
 
Rocker Arm said:
With the washer/shims fitted either side, how does the oil get to the needle rollers?

Should I drill a couple of holes in the shim?
Click to expand...
Which needle roller bearing, the clutch ones or the primary cover one? Either way, there's nothing pumping oil along the mainshaft. Lack of oil to those bearings isn't a known problem. There are plenty of others on a Laverda to worry about.
As for the hardened shims, you should find all you need in the UK. There's nothing specific about those shims.
These motorcycles are pretty simple contraptions with mostly rudimentary engineering practices.
Stick to basics.
You shouldn't need to machine the crank sprocket. You'll have difficulty finding another sprocket if the problem is elsewhere.
Is there nobody near you who knows these engines?
Paul
 
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