500 camchain tensioner assembly

[Lyndoneil]

I need some advice from anyone that has worked on 500 cylinder heads.
I'm fitting new valve stem seals and when I disassembled the cylinder head, the rear tensioner (adjustable) showed wear at the bottom where the crankshaft drives the camchain. The blade is straight and when refitting it is impossible if following the manual to get the slide to the rear of the pin in the crankcase, which is where it looks it probably should be positioned.
In the parts manual it shows the slide as curved, which would make it a lot more likely to fit to the rear, rather than the front, which pushes it against the camchain.
I'm guessing its going the wrong side, but would appreciate advice from someone who knows.
If so the tensioner will need fitting to the cylinder head before fitting the head to the barrels, so that the bottom of the slide is rear side of the pin, but it will make it a bugger to pull the camchain through the head tunnel.

 

[LaverdaIan]

I need some advice from anyone that has worked on 500 cylinder heads.
I'm fitting new valve stem seals and when I disassembled the cylinder head, the rear tensioner (adjustable) showed wear at the bottom where the crankshaft drives the camchain. The blade is straight and when refitting it is impossible if following the manual to get the slide to the rear of the pin in the crankcase, which is where it looks it probably should be positioned.
In the parts manual it shows the slide as curved, which would make it a lot more likely to fit to the rear, rather than the front, which pushes it against the camchain.
I'm guessing its going the wrong side, but would appreciate advice from someone who knows.
If so the tensioner will need fitting to the cylinder head before fitting the head to the barrels, so that the bottom of the slide is rear side of the pin, but it will make it a bugger to pull the camchain through the head tunnel.
View attachment 83908

Tensioner blade goes in after assembly of head, chain etc.

 

[Lyndoneil]

Tensioner blade goes in after assembly of head, chain etc.

Yes, that's as per workshop manual, but which side of that pin in the crankcase should the tensioner blade locate?

 

[LaverdaIan]

Yes, that's as per workshop manual, but which side of that pin in the crankcase should the tensioner blade locate?

I'm no engineer, but not sure if the blade even reaches that far..?
It's behind the chain so can't go anywhere but rear of chain.. I have seen that wear you are seeing on the base plate many times.. looks normal to me, correct chain adjustment may ease the issue, but you are right, some blades do have the bend at the bottom.. have seen and used both types. They can be a bit 'sticky' to get in place at times.. light taps at the top usually sort it..
HTH

 

[chrisk]

Looking at the pictures, if the blade reached the pin and was inserted between pin a chain, premature wear at pin site would be expected.

I’m no mechanic, but I’d expect the blade to go behind the pin, not before.. hence the reason for the pin.

 

[Rob]

I know bugger all about 500s, but standard practice on triples is to ensure the bottom of the tensioner blade has a bend applied if the aftermarket item is supplied straight. See Piet's comment -
https://laverdaforum.com/xf/threads/82109/post-160401

 

[LaverdaIan]

Yea Chris,
Thinking on it the blade goes behind the pin.. part of the whole tensioner application on the chain..
But the bend at the bottom of the blade certainly helps in fitting..
Ah, the 500's, a whole new world of their own.. no wonder nobody likes them..

 

[italmot25]

Hi,
The upper one is an orignal part of my 500 cc Laverda (no more available)
the other one belongs to a Zane 650. It can also be fitted to the 500. A little bend on the bottom will help as allready written....