750SF - Chains Specifications

Love..rda

Love..rda

Senior member
Location
Italy
Dear All
I'm trying to collect all chain specifications on my excel file.
Browsing in the forum I was able to find just the drive chain: 530 x 106 links.

What about the primary and the timing?

I have a second question: lately my bike looses the adjustment of the cams often. I think the screws are gone. Could be found something alike on the market?

With love

viteValvole.JPG
 
Do a search on here for Rotax tappet adjusters - they have a wide platform that maintains a wide contact area on the valve tip. They pivot on a ball and socket - solves the pitting problem common 750s. Martymoose has just fitted some to his SF. Not a straight fit - head needs to come off, rocker spindles out to access the rockers, grind a little off the underside of the rockers, valves out and take a smidge off the valve tips to allow clearance for the larger ball and socket - sounds like a lot of work but you won't be sorry you did it. Maybe best done during a top end rebuild if you're not comfortable pulling the head.
 
Loosing valve adjustment is rarely caused by the adjuster screws alone, especially if you still have the originals. More a case of rocker and/or cam lobes wearing away.

The often-used Fiat 500 screws should be modified before fitting, the radius of the tip is too small and will damage the valve tip. Good quality repros of the originals are available from some of the usual suppliers. ;) In Italy, try Augusto Brettoni in Barberino Val d'Elsa or Riccardo Oro in Breganze.

All Laverda engine chains are 06B spec, in simplex, duplex or triplex form. Does NOT apply for the 4-valvers.

piet
 
The often-used Fiat 500 screws should be modified before fitting, the radius of the tip is too small and will damage the valve tip.
Click to expand...
You can see it in the picture.# 3 is the Fiat part.
#1 original. #2 reproduction
 

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The duplex has 44links (false link included) right? And what about the triplex how many links? Close home there is a shop and they can supply the right chain if I can give the right specs.

I'll purchase the screws for understanding if the matter is just there or I have to go deeper.
The bike is running and when cold all is ok but warmer... timing chain and screws become noisy... very noisy...

All prof. are quite far from my place...

thanks for efforts and support.
 

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Was actually Lee who discovered this potential issue with SFs (and the cure) after going through about 2 cams and 2 sets of rockers. We only use a thin piece of wire bent in an L. As long as the slot that feeds the rocker spindles isn't blocked by the stud pushing against it, all is good. It's simple insurance.
 
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