Villiers 30C primary chain

[gambole1949]

Hi being a novice on this engine i thought i would seek a little help. I have purchased a new primary chain for this engine only to find it is just as slack as the old one, it states it is an endless chain but can I remove two links and replace a split link to take up the slack or is there a tensioner on the market for this type of engine. Many thanks Bud.

[iansoady]

Most Villiers engines "adjust" the primary chain by adding gaskets between the gearbox and engine castings. This is a very time-consuming and irritating job. I made a primary chain tensioner from Royal Enfield parts for the 1H engine fitted to my Francis Barnett Cruiser.

[33d6]

Ian is correct. The primary chain is adjusted by varying the the thickness of gaskets between the gearbox and engine.  As nowadays so many Villiers engines are used in pre-65 trials bikes it is common for trials engines to have a slipper tensioner fitted and several specialist firms offer them for sale. Many road riders prefer the slipper system.
The original Villiers system works well for the life of the engine but they did expect both sprockets and chain to be renewed together so that the new chain is running on new sprockets. It is then very much a ‘fit and forget’ system as all you have to is check the oil level occasionally as per the manual.

[gambole1949]

Thanks for the info guys, think i will have a go at making a tensioner, cheers Ian.