Hayter Friction Disc System

[Mick]

Here's a comparison between the old and new type friction disc systems fitted to many of the Hayter mowers such as Harriers etc.  The friction disc system hasn't changed much over the years other than now it's a two piece affair rather than one piece. The blade is driven by the outer edges of the disc only and would actually spin freely on the centre distance piece or spacer if it wasn't being bent and pushed against the edges of the disc.

Advantages: With the two piece is it's easier to remove, you no longer have to get the whole thing to slide off the crankshaft, which can often be rusted on solid if not properly maintained,.

Disadvantages: I can fall off when removing the blade. Some customers struggle to refit it correctly on its drive pegs, thus resulting in a bent disc which then wobbles on the hub causing vibration and noise.

Here's a diagram of the two types, (Note: these are not to scale). Just for those who don't know how it works.

Note: I forgot to add the spring washer which both bolts would be fitted with.